PROCEEDINGS OF THE 13TH CONFERENCE · 2009-06-10 · 4 13th Yellowfish Working Group Conference...

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13th Yellowfish Working Group Conference

FOSAF

THE FEDERATION OF SOUTHERN AFRICAN FLYFISHERS

PROCEEDINGS OF THE 13TH YELLOWFISH WORKING GROUP

CONFERENCE

STERKFONTEIN DAM, HARRISMITH 06 – 08 MARCH 2009

Edited by Peter Arderne

PRINTING SPONSORED BY:

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CONTENTS

PageParticipants 3Chairman’s Opening Address – Peter Mills 4 Water volumes of SA dams: A global perspective – Louis De Wet 6 The Strontium Isotope distribution in Water & Fish – Wikus Jordaan 13Overview of the Mine Drainage Impacts in the West Rand Goldfield – Mariette Liefferink

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Adopt-a-River Programme: Development of an implementation plan – Ramogale Sekwele

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Report on the Genetic Study of small scaled yellowfishes – Paulette Bloomer 26The Biology of Smallmouth & Largemouth yellowfish in Lake Gariep – Bruce Ellender & Olaf Weyl

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Likely response of Smallmouth yellowfish populations to fisheries development – Olaf Weyl

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Early Development of Vaal River Smallmouth Yellowfish - Daksha Naran 36 Body shape changes & accompanying habitat shifts: observations in life cycle of Labeobarbus marequensis in the Luvuvhu River – Paul Fouche

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Alien Fish Eradication in the Cape rivers: Progress with the EIA – Dean Impson 65 Yellowfish Telemetry: Update on the existing study – Gordon O’Brien 67Bushveld Smallscale yellowfish (Labeobarbus polylepis): Aspects of the Ecology & Population Mananagement– Gordon O’Brien

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Protected River Ecosystems Study: Bloubankspruit, Skeerpoort & Magalies River & Elands River (Mpumalanga) – Hylton Lewis & Gordon O’Brien

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Legislative review: Critical review of the legislative framework for angling – Morne Viljoen

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Smallmouth yellowfish: Status in the Great Kei Catchment – Unathi Tshayingca 86Status of yellowfish populations in Kwazulu-Natal – Rob Karssing 87 Free State Status Report – Johan Hardy 91Yellowfish Regional Report for the Western Cape 2008/9 – Martine Jordaan & Dean Impson

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River Monitoring in Limpopo Province 2009- Mick Angliss & Stan Rodgers 96Gauteng Report – Piet Muller 101 Northern Cape Regional Report – Carl Nel 103Yellowfish populations & RHP programme report in NW Province – 2009 : Part 1: Yellowfish Population Status Report – Daan Buijs Part 2: RHP Report Jan.2005 to March 2009 - Hermien Roux & Daan Buijs

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Main Issues/Concerns Raised & Resolutions taken at the Conference 149

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PARTICIPANTS

NAME ORGANISATION PHONE E-MAILAngliss, Mick Environmental Affairs, Limpopo 015-2959300 [email protected]

Arderne, Peter FOSAF Northvaal & YWG secretary 083 4577478 [email protected]

Bloomer, Prof.Paulette University of Pretoria 012 4203259 [email protected]

Buijs, Daan NW Prov. Conservation Services 083 3202727 [email protected]

Buthelezi, Siyabonga Gauteng Nature Conservation 072 1548863 [email protected]

De Wet, Dr Louis Waterlab 012-3491044 [email protected]

Du Toit, Thomas SAVE 082 4196526 [email protected]

Filter, Horst Guide & Land owner 034 9950017 none

Fouche, Paul University of Venda 072 2831391 [email protected]

Gerber, Ruan University of Johannesburg 011-5593442 [email protected]

Hardy, Johan Free State Nature Conservation 083 2312768 [email protected]

Hinrichsen, Etienne Aqua Eco 082 8221236 [email protected]

Jordaan, Martine CapeNature 021-8668019 [email protected]

Jordaan, Wikus Council for Geosciences 082 8632935 [email protected]

Impson, Dean CapeNature 082 4140020 [email protected]

Karssing, Rob EKZN Wildlife & YWG KZN 073 3794323 [email protected]

Lewis, Hylton ERYCA & EWT 082 9075164 [email protected]

Liefferink, Mariette Fed. of Sustainable Development 073 2314893 [email protected]

McGinn, Andrew Komati Gorge 017-8431497 [email protected]

Mills, Peter YWG chairman & FOSAF 082 5557972 [email protected]

Mincher, Bill FOSAF 011-8878787 [email protected]

Muller, Piet Gauteng Nature Conservation 072 1105075 [email protected]

Naran, Daksha SAIAB 046-6035800 [email protected]

Nel, Carl Northern Cape YWG 072 1997254 [email protected]

O’Brien, Gordon Zoology Dept. Johannesburg Univ. 084 5804161 [email protected]

Ramoejane, Mpho SAIAB 046-6035800

Rodgers, Stan Environmental Affairs, Limpopo 015-2959300 [email protected]

Roux, Hermien NW Prov. Conservation Services 082 4665966 [email protected]

Sekwele, Ramogale DWAF 082 5742234 [email protected]

Sinclair, Trevor Sundowner Adventures 083 4140391 [email protected]

Sinclair, Wayne Sundowner Adventures 083 4140391 [email protected]

Tempelhoff, Elize Beeld newspaper 083 3091192 [email protected]

Venter, Bernard Eco-Care Trust 083 4442790 [email protected]

Viljoen, Morne Environmental lawyer 083 3953929 [email protected]

Weaver, David Guide 083 3034230 [email protected]

Weyl, Olaf SAIAB 046-6035834 [email protected], Turner Guide 082 8815789 [email protected]

Wolhuter, Dr Louis FOSAF 011 6784156 [email protected]

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CHAIRMAN’S OPENING ADDRESS

Peter Mills

147 Mariana Ave, Clubview 0157. Email: [email protected] Welcome to the 13th Yellowfish Working Group Conference. Firstly, I would like to extend a special word of welcome to one of the YWG founder members who is also a Vice President of FOSAF, Bill Mincher. Also, welcome to Louis Wolhuter, a member of FOSAF and long time supporter of the YWG. It is also good to see a large number of old faces returning to this event year after year and showing your support. Of course it is good to see a number of new faces as well. The backbone, to my mind, of this conference is the presence and support by the Provincial Conservation Authorities. You at the coal face of conservation and your inputs regarding river health is an important component to this conference. The YWG was started by people like Bill, Louis and Pierre De Villiers to encourage fishing for yellowfish. We all know how popular this has become. But there has been a shift in emphasis over the years to that of having a greater conservation focus and this is because of a collection of complex matters. Surfing the web will show internationally acclaimed organisations like Trout Unlimited have also moved into the conservation realm – it’s a natural progression because good fishing will only take place in a healthy environment and with this comes conservation actions. Another reason for this shift in thinking in this country is because of the rapid deterioration of our river systems. As fly anglers we are on the water and witness, at first hand, the poor state of our rivers and waters. And, the situation is worsening by the day. The main culprits of this problem are the agricultural sector, mining and the local authorities who poorly manage the country’s waste water and sewage systems. The latter issue is seemingly a national dilemma. Anyone involved in conservation action will know that charity begins at home. In other words, any change that comes about for the better is by individuals doing extraordinary things within their own sphere of influence. We are fortunate therefore to have that kind of person at the conference. There is Horst, fighting to protect his own land from prospecting and mining. Not only is he working against mining companies but Government Departments who feel their mandate supersedes everything else. There is CapeNature who wishes to rehabilitate seriously degraded streams in the Western Cape region. Opposition is coming from seemingly friendly sources. The Northern Cape YWG are actively involved in encouraging river conservation by establishing river conservancies and preventing mining in the stream bed of both the Orange and the Vaal Rivers. Mariette Liefferink is actively working against the mining industry and Government who are polluting our ground water in the Krugersdorp area. Free State Conservation have done much to conserve the Vaal by establishing and supporting the Orange/Vaal River Yellowfish Management and Conservation Association. And, Thomas du Toit, who with his team at “SAVE” are doing much to keep the local authorities from polluting the Vaal because of poorly managed sewage facilities. This is where change will happen, at local level, driven by people who are affected by an environmental injustice and are willing to put in the extra effort to fix whatever is wrong.

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The strength of the YWG is in our diversity. Our structure is informal, as is our membership. We have no legal mandate to act but serve more as a forum to identify issues and exchange ideas of how to rectify them. To this end the YWG has:

• Produced the ‘State of the Yellowfishes in South Africa – 2007’ report in collaboration with the Water Research Commission.

• Coordinated and endorsed various scientific studies including the genetic work done in the Orange/Vaal system by the University of Pretoria.

• We have been involved at various levels with projects already mentioned above. • We keep members in touch through the circulation of a monthly news letter, and • Hold this workshop/conference on an annual basis in order to keep everyone in

touch with those involved, in one or other way, with river conservation, aquatic science/research and fishing.

In closing I would like to thank all of you who have come here to make presentations. It is you that are involved at various levels and making that difference I have been talking about. It is also here, with you, where much of the knowledge is held that can help make a difference to our river and aquatic systems. Finally, I would like to thank our sponsors; FOSAF for the ongoing sponsorship of the YWG and for SAPPI for assisting with the publication of the conference proceedings. I would also like to request that we all put our hands together for Peter Arderne, our secretary, who really keeps things together and for arranging this event. So, welcome to you all, thank you for supporting the YWG and I hope you all have fruitful and enjoyable conference.

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WATER VOLUMES OF SOUTH AFRICAN DAMS: A GLOBAL PERSPECTIVE

Louis De Wet Waterlab (Pty) Ltd, P.O.Box 283 Persequor Technopark 0020 : [email protected]

We often hear in the media about large potential shortages of natural and artificial resources such as fuel, electricity, water, etc. The sharp rises in the prices of these commodities are often a great source of worry to the general public. Given the recent conditions prevailing in South Africa with regards to sewage purification and waterborne diseases, one cannot help to wonder how scarce and expensive water is going to become. Due to the limited freshwater resources available currently in South Africa, and potable water reservoirs increasingly being threatened by pollution, the awareness of water quality amongst the general public has increased significantly. More often reports appear in the media covering incidents of sewage-, industrial- or mining pollution, or spillages of potentially toxic chemicals into the environment. We are bombarded by reports of fish- and crocodile mortalities, as well as infant deaths in hospitals due to polluted water. The past couple of months, the Cholera bacterium has been instrumental in a large number of deaths in Zimbabwe and the northern parts of South Africa. Each one of us, whether we are a user of water, or use water for sport, do have an obligation towards the water environment. This is a cultural-educational process where we as parents need to transfer this knowledge and compassion for water conservation to our children and grandchildren. Again often we hear in the media how water-scarce South-Africa is, and how we should conserve water, and invariably one asks oneself: “how much water is actually in our country”? It would obviously put our situation in perspective when we compare our situation with the state of dams and lakes in other countries and continents. Before we can really appreciate the magnitude of water volumes, a number of concepts need to be understood. A cube having the dimensions of 1X1X1cm or 1cm3 contains 1 milliliter of water. For a cube to contain 1 liter of water, the dimensions thereof should be 10X10X10cm or 1000cm3. Should a tank containing 1000 liter be required, the dimensions thereof could be 1X1X1m if a perfect cube is needed. In order to understand dimensions of dams, volume needs to be expressed as billions of cubic meters. If a cube of 1000X1000X1000 cubic meters is constructed, it will contain 1 000 000 000 or 1 billion or 109 cubic meters of volume. This is equivalent to 1 000 000 000 000 or 1012 or 1 Tera-liter of water. This may sound like an incredible amount of water, but this is more or less the volume of water contained by Bloemhof Dam. To be precise, this dam contains approximately 1.24 cubic kilometers of water at full capacity, and is ranked the 7th largest dam or reservoir in South Africa (DWAF, 2008). By comparison, the Vaal and Sterkfontein Dams are more or less double the size of Bloemhof Dam, containing 2.60 and 2.62 km3 respectively, while the Gariep, which is the largest dam in South Africa, contains 5.34 km3 of water (Table 1). This may sound a reasonably impressive figure, and one could be assured that sufficient amounts of water are available in South Africa, especially when all the volumes of dams are added together.

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According to Department of Water Affairs and Forestry figures, the total amount of water in South African dams on 2009-02-02 was 34.12 km3, representing an average capacity of 81%. Should we compare the amount of water available the amounts of water present on earth (fresh- and seawater), the figures are quite astounding. The sea contains approximately 1 320 000 000 km3 of water, which represents 97.2% of all water present on earth. Glaciers, ice-caps and the poles contain approximately 25 000 000 km3, or 1.8% of water, while 13 000 000km3 or 0.9% is found as subterranean or underground water. Freshwater in lakes, inland seas, dams and rivers represent only 250 000km3 (0.02%), while the moisture in the atmosphere represents a volume of 13 000km3 or 0.0001%. Table 1: South-African man-made Dams (Reservoirs) ranked according to volume (Top 10)

Name of Reservoir

River Province Full Storage Capacity (FSC) (km3)

% Full on 2009-02-02

Gariep Orange Orange Free-State 5.3406 82.3 Vanderkloof Orange Orange Free-State 3.1713 82.6 Sterkfontein Nuwejaar Spruit Orange Free-State 2.6169 98.8 Vaal Vaal Orange Free-State 2.6035 79.0 Pongolapoort Phongolo Kwazulu-Natal 2.2671 71.5 Katse Malibamatso Lesotho 1.5191 100.8 Bloemhof Vaal Orange Free-State 1.2402 88.3 Mohale Sequnyane Lesotho 0.8571 63.5

Theewaters Kloof Riviersonderend Western-Cape (winter rainfall) 0.4802 88.1

Woodstock Tugela Kwazulu-Natal 0.3733 96.8

Reference: Department of Water Affairs and Forestry : Weekly State of the Reservoirs. Data available on internet: http://www.dwaf.gov.za These figures would place the amount of water in South Africa in context to some extent on a global scale. However, to really establish the magnitude (or lack of) in comparison with that of other countries, let us start by flying over the northern border and visit the Cabora Bassa Dam. This dam, which is ranked as the 17th largest man-made dam in the world, contains 55.8 km3 of water, which is approximately 1.6 times more than the total amount of water available in South Africa. Upstream of the Cabora Bassa Dam, Lake Kariba contains a massive 180.6km3 of water, which places this dam in the 2nd place of largest dams in the world. The largest man-made dam in the world is the Owen Falls dam in Uganda, which contains 204km3 of water (Table 2). This, one would say, places the South-African water situation well into perspective, when compared to other dams in other countries. However, even the relatively large volume of the Owen Falls Dam pales into insignificance when the volume of this dam is compared to the large natural lakes of the world.

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Table 2: Largest man-made dams (Reservoirs) ranked according to volume (Top 10)

Name of Dam Reservoir River Country Year Completed

Nominal Volume (km3)

Owen Falls Victoria Lake White Nile Uganda 1954 [1]204, [2]205 Kariba Dam Kariba Lake Zambezi River Zimbabwe 1959 [1]180.6, [2]160.3Bratsk Hydroelectric Plant

Bratsk Resrvoir Angara River Russia 1964 169 – 169.3

Aswan High Dam

Nasser Lake Nile River Egypt 1971 [1][2]157

Akosombo Dam Volta Lake Volta River Ghana 1965 [1]150, [2]148

Daniel Johnson Manicouagan Reservoir

Manicouagan River Canada 1968 [1]141.85, [2]141.7

Guri Dam Guri Lake Caroni River Venezuela 1986 [1]135 W.A.C. Bennet Dam

Williston Lake Peace River Canada 1967 [1]74.3

Krasnoyarsk Hydroelectric Dam

--- Yenisei River Russia 1967 [1]73.3

Zeya Zeya Reservoir Zeya River Russia 1978 [1][2]68.4 [1]International Commission on Large Dams Database [2]Avakayan, A.B. & Ovchinnikova, S.P. (1971). Foreign experience and techniques. Hydrotechnical Construction, 5(8) : 773-777. The largest freshwater lake in the world is Lake Baikal in Russia, which contains approximately 20% of all freshwater on earth. This is equivalent to a massive 23 000km3 of water! This lake is also the deepest (Max Depth : 1 637m : Average Depth : 749m) and second longest (630km) lake in the world. At a height of 1100 km above earth, this lake is easily observed by satellite (Figure 1). The largest inland water-body is the Caspian sea in Asia, which has a volume of approximately 78 200km3. However, this lake is a saltwater lake, but is still considered per definition as a lake (Table 2). Lakes, in contrast to storage dams, are created by natural phenomenon such as tectonic movements, glacial action, or large tears in the earth’s crust. Lake Baikal, as well as Lakes Malawi and Tanganyika in the rift valley of Africa, are examples of long and deep lakes formed in the crust of the earth’s crust (Table 2). The largest volume of freshwater is found in the northern hemisphere, while 60% of the world’s lakes are found in Canada. The state of Manitoba harbors more than one hundred thousand lakes, while Finland is known as the “land of a thousand lakes” – in fact, there are 187 888 lakes in this country, of which 60 000 are considered as large lakes. It is interesting to note from Table 2 that the top 2 largest lakes are in Russia, while the larger lakes are in Canada and America. The two rift valley lakes, Malawi- and Tanganyika in Africa, count amongst the largest in the world.

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Figure 1 Lake Baikal in Russia from a height of 1100km. (Photo : Google Earth) To really comprehend the enormous size of Lake Baikal, in comparison with the absolute relative water scarcity in our country, the outlines from this lake traced from a satellite photo of this lake, super-imposed on South Africa, is shown in Figure 2. If we were blessed with a Lake Baikal in South Africa, it would have stretched from Gariep Dam in the south, through the Orange Free State to Johannesburg in the north. Indeed, our largest dams look like mere specs when compared to the enormous size and volume of this lake. If we compare the volume of Lake Baikal (23600 km3) with the total volume of water available in South Africa (31.72 km3), this lake is a massive 744 times larger in volume. One can only speculate what the positive social and economic impact on South Africa would have been, should this lake have been present in our country.

610 km

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Table 2: Top 10 largest lakes in the world according to volume

Lake Region Surface Area (km2)

Length (km) Maximum Depth (m)

Volume (km3)

Caspian Sea[saline]

Azerbaijan- Russia- Kazakhstan- Turkmenistan- Iran

371 000 1 199 1 025 78 200

Baikal Russia 31 500 636 1 637 23 600

Tanganyika

Tanzania- DRC- Burundi- Zambia

32 893 676 1 470 18 900

Superior Canada – U.S 82 414 616 406 12 100 [3]Michigan-Huron

Canada – U.S 117 702 710 282 8 458

Malawi Malawi- Mozambique- Tanzania

30 044 579 706 8 400

Vostok Russia 15 690 250 900-1000 5400 + 1600

Victoria Kenya- Tanzania- Uganda

69 485 322 84 2 750

Great Bear Canada 31 080 373 446 2 236 Great Slave Canada 28 930 480 614 2 090 Ontario Canada – U.S 19 477 311 244 1 639

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Figure 2 South-Africa from a height of 1100km showing the relative size of Lake Baikal in comparison with SA as whole and our largest dams. (Photo : Google Earth)

In our efforts to conserve water and supply this precious resource to a fast-growing population, every effort is being made to contain as much possible water in dams. The development of the Lesotho Highland scheme was aimed at supplementing water for the demands of Gauteng with the highest human population, and an extremely high concentration of industries and mines. However, even this source would not in the coming future be sufficient to comply with the demands of this area. Any significant prospects of the construction of large water storage dams in South Africa is indeed remote, and we are indeed dependent on further developments of the Lesotho Highlands Scheme to supplement our water supply. Indeed most of us live in a world where a false sense of security is a driving factor. As long as there is water in our taps, and the lights work, the real world outside does not really matter. We don’t want to think of these things, and do not try to place orders of magnitude into perspective with our own small world in which we live. We are not lucky that we live in a geographical area or climatic region (as the northern hemisphere) where we have a high rainfall and sufficient storage dams. In addition, we are not blessed with the tectonic or glacial action to provide us with great natural lakes. Even if we had only the smallest of the Great Lakes, Lake Ontario, with a volume of 1 640km3 in South Africa, we never would have a problem with water supply in our country. And yet still, the majority of us have this don’t-care attitude towards water. By letting the tap run when we brush our teeth or shave in the morning, over-filling our baths, or using too much water when we wash our cars, we exhibit a culture most of us practice without any thought or conscience. These things may seem small, but the additive effect by a total population practicing the same bad habits

610 km

Gariep Dam

Van der Kloof Dam

Bloemhof Dam

Vaal Dam

Outline of Lake Baikal

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makes us as guilty as the mine, factory or sewage treatment works discharging untreated effluent into a river. We have indeed a cross-road in South-Africa as far as water availability and pollution is concerned. There are a significant number of practical and socio-cultural factors which work negatively against South-Africa and it’s population, and may in future become factors which may mean the difference between life and death for many of us:

Low rainfall over most of South Africa Surface and underground water resources are limited No large natural lakes Any available water is stored in relatively small dams South Africa has a rapidly growing population There is a high water demand by mining, industry, etc. Water cannot be piped from neighboring countries such as Zimbabwe (Cahora

Bassa) Pollution of limited water resources is increasing significantly Education on water conservation is still insufficient Indifferent attitude of South Africans towards water conservation.

In retrospect, South-Africa is indeed not blessed with an abundant water supply. The little water we have is increasingly being placed under severe pressure both by increasing demand, as well as a social culture amongst South-Africans which leaves a lot to be desired.

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THE STRONTIUM ISOTOPE DISTRIBUTION IN WATER AND FISH: WITHIN MAJOR SOUTH AFRICAN DRAINAGE BASINS.

L.J. Jordaan1, L.P.D. de Wet2, M.C. Rademeyer3 and V. Wepener4 1 Council for Geoscience, Private Bag X112, Pretoria, 0001, South Africa. E-mail: [email protected]

2 Waterlab (Pty) Ltd, PO Box 283, Persequor Park, Pretoria, 0020, South Africa. E-mail: [email protected]

3 PO Box 4082, Robina, 4230, Queensland, Australia. E-mail: [email protected] 4 Department of Zoology, University of Johannesburg, PO Box 524, Auckland Park, 2006, South Africa. E-

mail: [email protected] Introduction The Council for Geoscience was requested in early 2006 to find a scientific method of minimizing illegal entries at major South African freshwater sport fishing tournaments. The organizers of these competitions suspected that some participants were entering large fish that were not caught during that specific competition and then illegally claiming substantial prizes. These prizes usually include cash, vacations, property, ski boats, cars, trailers and a range of fishing, camping and outdoor gear. There is thus serious competition for these prizes and much unhappiness amongst competitors when foul play is suspected. This study was undertaken to find ways of linking fish to specific environments. The initial approach was to chemically analyze water and fish from specific dams for as many components as possible and then to find correlations between the fish chemistry and chemistry of their specific habitat. The approach is based on the assumption that fish living in a specific dam should be in equilibrium with that dam. This implies that there should be a measurable chemical correlation between the dam sediments, dam water and fish organs. Sr (strontium) is an ideal element for this type of study as it is present in high enough concentrations for all analytical purposes, while Sr isotope ratios remains independent of biological processes. It has also been used very successfully in solving similar problems relating to the illegal ivory trade (Van der Merwe, et.al., 1990). Dams are very special habitats as fish migration and movements are limited by dam walls and usually very shallow waters at the inlets. Large fish of the size that are caught during fishing tournaments are therefore expected to spend their entire lives within a relatively limited area. Analytical Method Trace element concentrations in fish tissue, liver, gills and bone samples were investigated as possible methods to link fish to a specific dam. This approach is complicated by the dilution of element concentrations in the dam and river waters during the rainy season. The biology, species and sex of the fish also plays a role. The very clear correlation between the Sr isotope ratios of dam water and the bones in fish fins however proved to be the most useful. Common Carp, Mozambique Tilapia, Sharptooth Catfish and Largemouth Bass formed the major focus of the study while limited samples of a few minor species were also included. A database was established for major dams where fishing tournaments took place, but it was later extended to also include some minor dams and rivers. The investigation initially concentrated on Loskop Dam where most irregularities were suspected, but was later extended to the entire Olifants River drainage basin as well as to the Mgeni River basin, the Orange/Vaal River basin and the Crocodile River basin.

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The analytical method for the water samples, consisted of filtering through a 0.45 micron filter and drying down a two liter sample to concentrate the Sr, followed by purification of the sample using Bio-Rad AG50Wx12 cation resin. The purified sample could then be analyzed for its Sr isotope ratio using a Finnigan MAT 261 Thermal Ionization Mass Spectrometer. Bone from the dorsal, ventral or pectoral fins of fish is a suitable material for study as it is formed throughout a substantial portion of the fish’s life cycle while incorporating Sr from the surrounding aquatic medium. All fish fins were physically removed from the collected fish and dried in an oven at approximately 75 °C. All soft tissues were removed followed by pulverizing in an agate swing mill and dissolution in nitric acid. Sr was extracted from the acid solution again using Bio-Rad AG50Wx12 cation resin followed by analysis on the above mentioned mass spectrometer. A set of five samples were analyzed at the University of Cape Town on a HR-ICP-MS for verification. Results The data obtained in this fashion indicated that there is a definite and measurable correlation between the 87Sr/86Sr isotope ratio of the fins and the dam water in which the fish lived while developing these organs. Table 1 lists the average 87Sr/86Sr ratios of fish and water samples from Loskop Dam. This parameter is independent of the specific fish species, the sex of the fish, the age of the fish and the season in which the fish was caught. Sr ratios were in some cases determined over a three year period in which time there were no significant changes in these ratios. It can therefore be extrapolated that fish from a specific dam can be correlated with the water from that dam and it would therefore be possible to verify whether fish presented at a fishing competition were in fact caught in the dam where the fishing competition was held. The only limiting factor is that there is not a large natural variation in Sr ratios and therefore some dams may have similar ratios, which would imply that fish would be indistinguishable in terms of their Sr isotope ratios. Fortunately there are large natural variations among most of the dams of the Olifants River making Loskop Dam clearly distinguishable. The range of values for water samples from any specific dam is generally smaller than the range of values for fish samples from that same dam. At some dams, like Middelburg, Witbank, Doornpoort and Loskop the range of values for fish bones slightly exceed the upper limit for the range of values for water samples.

Table 1. Strontium isotope composition of fish and water samples from Loskop Dam

Sample Tissue Laboratory InstrumentAverage

87Sr/86SrMinimum 87Sr/86Sr

Maximum87Sr/86Sr

n

Water Surface CGS TIMS 0.728904 0.728487 0.729804 7 Cyprinus carpio Dorsal spine CGS TIMS 0.731084 0.728923 0.732730 21Cyprinus carpio Ventral spine CGS TIMS 0.731274 0.730982 0.731566 2

Cyprinus carpio Dorsal & ventral spines CGS TIMS 0.730796 0.729586 0.731842 8

Cyprinus carpio Dorsal & ventral spines UCT HR-ICP-MS 0.730460 0.729233 0.731332 5

Oreochromis mossambicus Dorsal fin spines CGS TIMS 0.731388 0.730440 0.732303 6

Clarias gariepinus Pectoral spines CGS TIMS 0.728734 0.728734 0.728734 1

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In comparison, data from the Mgeni River basin (KwaZulu-Natal) show a constant increase in 87Sr/86Sr ratio from Midmar Dam, through Albert Falls and Nagle Dam to Inanda Dam. The 87Sr/86Sr ratio of fish from Inanda Dam can again be correlated perfectly with the water from Inanda Dam. In the Crocodile River basin (Gauteng/North West Province) the Sr isotope ratios are more complex. A slight increase in the 87Sr/86Sr ratio is observed moving downstream except for Roodekopjes and Vaalkop Dams where a decrease in the Sr isotope ratio is observed. The Orange/Vaal River basin is significantly larger than the other systems that were studied. In this system a good correlation again exists between the 87Sr/86Sr ratio of fish and water for both Vaal and Bloemhof Dams. Discussion Sr isotope ratios were in all cases determined on the dissolved Sr fraction. The origin of this fraction can therefore be either from the natural weathering of upstream geological units or from an upstream anthropogenic source. An investigation of the Vaal and Orange rivers by De Villiers, et.al. (2000) showed that much of the Sr isotope ratio of a river is determined by the isotope ratio of the predominant geological strata in the upper part of the catchment basin. In the upper Olifants River system there is certainly ample proof of additions to the river water from mine, municipal or industrial sources. The Sr isotopic ratios of the water samples were however constant over a three year period suggesting that the main source may be the more consistent geological environment. Most of the larger fish that were analyzed were also much in access of five years old indicating that a relatively constant Sr source may have been available to them for several years. The dams may also have a buffering effect on the Sr isotope ratio of the river water. Dams are remarkably homogenous, at least within the upper layers where the samples for isotope analysis were taken. This is also evident from the metal and anion content. In larger dams with only one major inlet the Sr isotope ratio is very constant, even close to the inlet. In large dams with two major inlets like the Vaal or Bloemhof dams, slight differences may exist between the inlets. In the Olifants River basin, the Middelburg, Witbank and Doornpoort Dams have a similar Sr isotope ratio, which is distinct from Bronkhorstspruit Dam. Loskop Dam which is downstream from these dams has a Sr isotope ratio between these two extremes, indicating mixing of water from upstream sources. Similarly Arabie Dam, which is even further downstream, shows a Sr isotope composition between the composition of Loskop Dam and the dams in the Elands River. The Sr isotope composition of a single dam may therefore be the result of several factors that may give a dam and the fish living within it a distinctive character and therefore provide excellent possibilities for forensic applications. References De Villiers, S., Compton, J.S. and Lavelle, M. (2000). The strontium isotope systematics of

the Orange River, Southern Africa. S.A. Jour. Geol. Vol. 103. p237-248. Van der Merwe, N.J., Lee-Thorpe, J.A., Thackeray, J.F., Hall-Martin, A., Kruger, F.J.,

Coetzee, H., Bell, R.H.V. and Lindeque, M. (1990). Source-area determination of elephant ivory by isotopic analysis. Nature Vol. 36. p744-749

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OVERVIEW OF ACID MINE DRAINAGE IMPACTS: IN THE WEST RAND GOLDFIELD

Mariette Liefferink Federation for a Sustainable Environment, Postnet suite 87, P/Bag X033, Rivonia 2128. Email:

[email protected]

The Witwatersrand* has been mined for more than a century. It is the world’s largest gold and uranium mining basin with the extraction, from more than 120 mines, of 43 500 tons of gold in one century and 73 000 tons of uranium between 1953 and 1995. The basin covers an area of 1600 km2, and led to a legacy of some 400 km2 of mine tailings dams and 6 billion tons of pyrite tailings containing low-grade uranium. (Reference: “A Remote-Sensing and GIS-Based Integrated Approach for Risk Based Prioritization of Gold Tailings Facilities – Witwatersrand, South Africa”) (*The Witwatersrand Mining Basin is composed of the Far East Basin, Central Rand Basin, Western Basin, Far Western Basin, KOSH and the Free State gold mines.) 120 Years of gold mining activity within the gold mining areas of the West Rand and Far West Rand (Wonderfonteinspruit Catchment Area – Figure 1) and the non-internalisation of negative externalities, have resulted in "…the mean values for the Wonderfonteinspruit samples … to exceed not only natural background concentrations, but also levels of regulatory concern for cobalt, zinc, arsenic, cadmium and uranium, with uranium and cadmium exhibiting the highest risk coefficients.”

Figure 1

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The Wonderfonteinspruit valley is densely populated because of its agricultural value and presence of gold mines. The majority of the inhabitants live in informal settlements, using contaminated ground- and stream water for personal hygiene and drinking. With above-average infection rates of HIV/AIDS and chronic and acute malnutrition, this subpopulation is particularly vulnerable to additional stress of the immune system by contaminants such as uranium. Uranium is generally associated with the gold ores of the Witwatersrand. Uranium and its radiogenic progeny are therefore found in many of the residues and wastes produced in the mining and processing of gold. (Reference: “Radiometric Surveying in the Vicinity of Witwatersrand Gold Mines” by H. Coetzee.) Uranium is identified as the principal contaminant of concern within the gold mining areas of the West Rand and Far West Rand (Wonderfonteinspruit Catchment Area). Uranium is emitted by a single industry namely the gold mining industry. Uranium is radioactive and chemically toxic with an extremely long half-life. It has been shown that the risk posed by uranium, an important by-product of gold mining in the West Rand and Far West Rand and an identified hazardous component of the wastes and effluents from gold mining activities, occurs due to both radiotoxicity and chemical toxicity with, in some cases, the chemical toxicity dominating over the radiotoxicity. ( Reference: “South Africa’s Challenges Pertaining to Mine Closure – The Concept of Regional Mining and Closure Strategies” by D.M. van Tonder et al; “Establishing a Framework for Intervention and Remediation of Radioactive Contamination from Gold Mining – Learning from the Past” by J.F. Ellis.) The documents that hold the history of the Wonderfonteinspruit would exceed 5m if stacked. The bibliography of relevant literature that has been compiled would, if printed, extend to nearly 120 pages. In this paper copious reference will be made to the following official public domain. Reports:

• An Assessment of Sources, Pathways, Mechanisms and Risks of Current and Potential Future Pollution of Water and Sediments in Gold-Mining Areas of the Wonderfonteinspruit Catchment - Report to the Water Research Commission. Compiled by Henk Coetzee, Council for Geosience - WRC Report No 1214/1/06 ; ISBN No 1-77005-419-7 – March 2006.

• Contamination of wetlands by Witwatersrand gold mines – processes and the economic potential of gold in wetlands - Henk Coetzee, Jaco Venter & Gabriel Ntsume - Council for Geoscience Report No. 2005-0106

• A comprehensive radiological risk assessment performed by German physicists on behalf the National Nuclear Regulator, the radiological risks to the public, was published in the Report entitled: Radiological Impacts of the Mining Activities to the Public in the Wonderfonteinspruit Catchment Area.

The impacts of mining in the West Rand and Far West Rand on the surface and ground water system, in particular impacts related to uranium, with elevated levels of radioactivity are well documented. It was found that tailings dams within the Wonderfonteinspruit Catchment Area contain 100 000 tons of U. Groundwater pollution arises as a result of the poorly designed and managed tailings dams, which allow leachate to seep into the underlying aquifers and due to the lateral migration of water from the shallow portions of flooded mine voids into the surrounding aquifers. An important local groundwater issue has arisen in the Far West Rand, where mine

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tailings dams were established in sinkhole prone areas, with the stated aim of encouraging drainage of the tailings, and where tailings were used as a fill material after the development of sinkholes in the dolomite which covers large parts of the area. In both of these cases, uraniferous tailings which can have a severe impact on water quality were deliberately introduced into a major aquifer. (Reference: “South Africa’s Challenges Pertaining to Mine Closure – The Concept of Regional Mining and Closure Strategies” by D.M. van Tonder et al.) It was found that: • 50 Tons of U are discharged annually into the Wonderfonteinspruit.

• Through seepage/percolation 24 tons U, with concentrations 1 000 to 1 million higher than the background U concentrations, enter the Wonderfonteinspruit annually.

• From point sources 12 tons of U are discharged annually into the Wonderfonteinspruit.

• Stormwater discharges10 tons of U annually into the Wonderfonteinspruit.

• Sinkholes, historically filled with uraniferous tailings, will become secondary sources of U contamination, when mines close and pre-mining flow patterns and volumes are restored.

It was found that the chemical risk quotient associated with drinking river water is 6,67 and the radiological risk quotient is 2,22. Both the numbers are above 1,00 meaning that there is a risk of ill-health effects by drinking water from contaminated streams in the Wonderfonteinspruit. In terms of the NNR’s Report “Radiological Impacts of the Mining Activities to the Public in the Wonderfonteinspruit Catchment Area” it was found that: • The measured uranium content of many of the fluvial sediments in the

Wonderfonteinspruit, including those off mine properties and therefore outside the boundaries of licensed sites, exceeds the exclusion limit for regulation by the National Nuclear Regulator.

• For approximately 50% of the 47 sampling sites, the calculated incremental doses of the respective critical group are above 1 mSv per annum up to 100 mSv pa (548 mSv pa Blyvooruitzicht Mine/Bridge Carletonville)

• The radioactive contamination of surface water bodies in the Wonderfonteinspruit catchment area caused by the long-lasting mine water discharges and diffuse emissions of seepage and runoff from slimes dams poses radiological risks to the public resulting from the usage of polluted environmental media;

• The pathway sediment→SPM →cattle→milk/meat→person (“SeCa”) can cause radioactive contamination of livestock products (milk, meat) resulting in effective doses of the public in some orders of magnitude above those resulting via the pathway “WaCa’’.

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Mining has resulted in the dispersal of radioactive material into the environment via windblown dust, waterborne sediment and the sorption and precipitation of radioactivity from water into sediment bodies. The use of contaminated material and mine residues in construction has also been identified as a means of dispersal of radioactive material into the environment. Contaminated areas have been identified and the need for comprehensive monitoring and study as well as epidemiological studies in affected communities are recommended. Figure 2 shows the surface distribution of radioactive material for the West Rand goldfield.

Figure 2 In terms of the NNR’s “Status report on the actions arising from the study of radiological contamination of the Wonderfonteinspruit Catchment Area (WCA)” it was found:

• The study undertaken by the NNR has confirmed the presence of radioactive contamination in the WCA.

• Preliminary results of analyses conducted on produce grown in the area have indicated that the dose levels are of radiological concern to the regulator.

• The study has also highlighted the need for all the regulators to work closely together since the contamination includes non radiological contaminants such as heavy metals and salts.

• The issues involved in the contamination in the Wonderfontein Catchment Area are complex.

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In terms of the WRC Report 1095/1/02 and the WRC Report 1214/1/06: • Andries Coetzee Dam has U concentrations of 900mg/kg**

• Upper Wonderfonteinspruit has U concentrations of 1 100 mg/kg

• Klerkskraal Dam, a dam which has not received any mine effluent has U concentrations of 1 mg/kg

• The radioactivity in the Tudor Dam was found to be 10 000 – 100 000 Bq/kg***

• The radioactivity in the Sluice was found to be 1 000 – 10 000 Bq/kg

• The radioactivity in the Andries Coetzee Dam was found to be 1 000 – 10 000 Bq/kg

• The radioactivity in the Attenuation Dam was found to be 100 – 1 000 Bq/kg

• The radioactivity in the Donaldson Dam was found to be 100 – 1 000 Bq/kg

**16mg/kg uranium is equivalent to an activity concentration of 0,2Bq/g, the limit for regulatory control set by the NNR. ***Regulatory Limit: 500 Bq/kg The following are examples of radioactive sites within the West Rand and Far West Rand: Tudor Dam The Tudor dam is located in the south eastern portion of the headwaters of the WCA. The dam was built before the establishment of Rand Water for water supply to the mine(s) in the area. The area behind the dam is currently dry and being mined to recover gold from the sediments that have accumulated as a result of inefficient mining practices by today’s standards. At the time of the field visit it appeared that the re-mining had ceased. During the inspection there was no inflow or outflow of water and the dam was dry. There is however evidence that during rainy periods that water would flow into and out of the dam. The soils and sediments at the site are potentially contaminated with radionuclides. There is evidence of sulphate “evaporates” on the surface of the sediments. The specific activity of uranium in the soils and sediments behind the dam are high, 8000-10000 Bq/Kg with radium 226 at 1700-2800 Bq/Kg. Stream Bottom 150m Downstream of Tudor Dam This site is a dry “wetland” below Tudor Dam. The channel contained well-sorted fine sediments, most likely, slimes deposited from the overflow from Tudor Dam. Uranium and radium specific activity levels were high here, at 2000 Bq/kg for uranium and 1200 for radium, as would be expected if they originated from the Tudor Dam (contamination of radioactive material exceeding clearance levels of 0.5 Bq/g per nuclide and will need to be remediated prior to the site receiving clearance). The site presents medium-high uranium and/or radium levels, exceeding national or international standards.

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Mine water from Doornfontein Shaft and Runoff Water from Slimes Dam This area is largely problematic due to the poor housekeeping at the site. There was a leak at the pump station that was not contained and has not been addressed. There is evidence of slimes around and downstream of the pump station. There was also evidence of cattle grazing around the pump station, with relatively fresh manure directly on top of the escaped slimes. Radiation from water and the slimes was unacceptable, according to the reports, particularly in the form of radium, at 1750 Bq/kg. Former Wetland Downstream of Lancaster Dam

The area behind the Lancaster Dam appeared to have filled with slimes that have recently been mined. The Dam had been breached by heavy equipment so as to allow acidic slimes water and fine slimes to drain into the pond and wetland immediately below the dam. On this downstream side of the dam, there is an orange pool of settled slimes, filled with acid mine drainage water, where there are few plants and there are signs of dead wildlife. Dry slimes were observed blowing throughout the Lancaster dam site. Drainage of water from this area was ongoing at the time of the site visit. As the site presently exists it is suspected that acutely toxic acidic drainage is currently draining from the site through the breach in the dam into the pond and wetland immediately below the dam. Because of the lack of any flow restriction this could become an extremely serious situation following a heavy rainfall. The main pollutants are suspected of being acidic water and associated toxic metals arising from oxidation of sulphides such as iron sulphide, also known as pyrite. The stream presently passes through the breach in the Lancaster Dam, with visible seepage of slimes from the Lancaster Dam into the stream which forms the upper Wonderfonteinspruit. At present the U and other heavy metals, such as cadmium, copper, zinc, arsenic and cobalt are adsorbed in the sediment. Plausible environmental conditions such as:

• Acid mine drainage

• Acid rain

• Drying out of the sediment and influx of water

• Dredging operations

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• Tailings spillages

• Turbulence caused by cattle drinking the water or children playing in the water can cause the mobilization or transport of uranium in the Wonderfonteinspruit.

In 2002 in the Krugersdorp-Randfontein area water had started to decant from a number of shafts into the Tweelopiespruit and the Wonderfonteinspruit. The water had a pH of 2.2. It is commonly known as Acid Mine Drainage (AMD). The combination of the pH and redox driven reactions resulted in a measured uranium concentration of 16mg/l of the Robinson Lake, and resulted in the NNR declaring the lake a radiation area. The background U concentration in water is 0,0004mg/l. In terms of the DWAF regulations for drinking water, the U concentration should not exceed 0.07mg/l and for irrigation, 0.01mg/l. Acid Mine Drainage (AMD) is responsible for the most costly environmental and socio-economic impacts. Production of AMD may continue for many years after mines are closed and tailings dams decommissioned. AMD is not only associated with surface and groundwater pollution, degradation of soil quality, for harming aquatic sediments and fauna, and for allowing heavy metals to seep into the environment. Long-term exposure to AMD polluted drinking water may lead to increased rates of cancer, decreased cognitive function and appearance of skin lesions. Heavy metals in drinking water could compromise the neural development of the fetus which can result in mental retardation. If indeed the extent of “… problems related to mining waste may be rated as second only to global warming and stratospheric ozone depletion in terms of ecological risk” (EEB, 2000), then the Witwatersrand gold mining area of South Africa is at serious risk.

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The impacts of the mine void water on the surface water system, in particular the increased salt loads, can be inferred from the subjoined figure (Figure 3)

Volumes and loads

• Polluted water is discharged into a receiving environment– Volume = ~25Ml/d

– Salt content = ~4g/l

– Salt load = ~100 tons per da

Photo: Courtesy Dr. Henk Coetzee

20t 20t 20t 20t 20t

Figure 3 In terms of “A hydrogeological assessment of acid mine drainage impacts in the West Rand Basin Gauteng Province” it was found that the:

• Decanting Volumes are currently between 18 and 36 ML/per day • An unqualified volume still escapes downstream • The decant takes place at the north/south intercontinental water divide with

impacts to both the Tweelopiespruit (to the North) and the seepage of AMD into the Wonderfonteinspruit during heavy rainfall events (to the South)

• The environmental critical level not absolute decant management solution • Dolomitic Outlier is not a low permeability barrier. There are faults and fractures

In terms of the Harmony Gold EIA Report, entitled: “ Hydrological/Chemical aspects of the Tweelopie-/Riet-/Blaaubankspruit, with specific reference to the impact water, decanting from the Western Basin Mine Void, has on the system” it was found:

• The AMD causes accelerated void formation in the dolomite of the Zwartkrans compartment.

• The void created by the mine void water is 8 960 m3 and was formed in only 2.5 years. The Wondercave was formed over a period of millions of years.

• There are people living and operating businesses in the area and these people should be warned about the potential ground instability in their area.

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• The potential greatest disaster could occur if part of the N14 Roadway collapses. This road carries a high traffic load, as it is the main arterial between Johannesburg and Botswana.

The DWAF and the NNR has established the Wonderfontein Regulators Steering Committee (WRSC) on the 21 st of December, 2006. This Committee, consisting of officials of all the relevant Departments as well as from the Local Municipalities, will steer the whole remediation process. The NNR will chair the WRSC and the NNR will have stricter control on the discharges from the mines. The DWAF will ensure that all water use licenses be issued to the mines as soon as possible in an endeavour to stop contamination of the Wonderfontein Spruit. All regulators agreed that remediation of the hotspots was required. A Team of Experts (TOX) was appointed to determine the priority hotspots. The mines were approached to contribute financially towards the remedial work to be done as per the findings of the TOX. The approach will therefore be to get community involvement as soon as possible and for this purpose the author of this document was appointed by the DWAF as the convener of the public involvement and participation component of the remediation of the Wonderfonteinspruit Catchment area. The following closure risks remain:

• Latent impacts may take decades, or even centuries, to manifest themselves.

• Inherent water quality risks

• Gold mine ore bodies – associated with radionuclides

• Hydrological interconnections between mines – cannot be considered in isolation

• Tailings dams and waste rock dumps can never be maintained in completely reducing environment - water risk ad infinitum

• Long term risk re formation of sinkholes

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ADOPT-A-RIVER PROGRAMME: DEVELOPMENT OF AN IMPLEMENTATION PLAN FOR SOUTH AFRICAN RIVERS

Ramogale Sekwele Department of Water Affairs and Forestry, Directorate Resource Quality Services, Private Bag X313, Pretoria,

0001. Email: [email protected]

The Department of Water Affairs and Forestry has initiated the “Adopt-a-River” programme as a means of creating awareness among all South Africans of the need to care for our scarce water resources and to facilitate their participation in the protection and management of water resources. This programme was initiated when a question was asked in Parliament whether South Africa’s rivers were healthy and fit for use. Some Members of Parliament volunteered to adopt a river and serve as patron for that river, as a sign of their own commitment in protecting the health of our rivers. A phased approach is being followed for its implementation. The first phase that was completed in 2007 was to draft a Strategic Framework for the development of the Adopt-a-River programme. The second phase (current) which started in 2008 is focusing on the development of an implementation plan and is due for completion in July 2009. This entails the development of an appropriate model, institutional framework and governance structure for implementing the Adopt-a-River programme in South Africa. It also includes the development of communication structures, and manuals and other training material for volunteer monitoring and to support Adopt-a-River type of activities. The project provides information on some of the success stories and challenges that the programme is facing in the country where the ethic of “volunteerism” is not as well established as in first world countries like the USA, Canada and Australia. Piloting of the Adopt-a-River programme will commence towards the end of 2009. The programme design and the implementation plan will be tested in a selected river in each Province and the design will be revised where practical constraints render that necessary as part of phase three. Phase four will focus on development of tools, techniques and training material and will take place on an ongoing basis, as well as information and task sharing with interested parties. In this final phase the Adopt-a-River programme will be expanded to any area where interested parties would want to participate in the Adopt-a-River programme and learn about the protection and management of their water resources. The aim will be to mobilise volunteers to assist in keeping the South African rivers safe for use and to safeguard the health of the rivers, wetlands, estuaries and reservoirs in a sustainable way. Typical challenges are creating a workable institutional arrangement, sustainable funding, and issues around management and use of data collected by volunteers and others. More information on the Adopt-a-River programme can be obtained from Ramogale Sekwele at DWAF, Directorate: Resource Quality Services ([email protected] / 012 808 9500) or Linda Rossouw ([email protected]).

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REPORT ON THE GENETIC STUDY OF SMALL SCALED YELLOWFISHES

Paulette Bloomer1, Carel Oosthuizen1 & Rob Karssing2

1Molecular Ecology and Evolution Programme, Dept of Genetics, University of Pretoria, Pretoria, 0002 2Biodiversity Division, Ezemvelo KZN Wildlife, P.O. Box 13053, Cascades, 3202

The main focus of the presentation was diversity within the KwaZulu-Natal (KZN) yellowfish Labeobarbus natalensis, for which the sequencing of a mitochondrial DNA (mtDNA) region has been completed. A short overview of the research agenda for 2009 and 2010 was also provided. Progress during 2008 and early 2009 During 2008 DNA sequencing of the mtDNA control region was completed for a pilot study of variation within L. polylepis for a WRC report (see O’Brien ‘Overview – Smallscale yellowfish study’). The mtDNA study of the within species variation in L. natalensis was completed as part of an NRF funded research initiative to improve our understanding of endemic freshwater fish biodiversity in South Africa. Between 2003 and 2007 samples were collected from ~ 25 sites, largely representative of the distribution of L. natalensis. DNA sequences were successfully generated for 182 samples. Analysis of these data revealed considerable genetic diversity in the species. Our previous research found 22 unique lineages among 92 Orange-Vaal yellowfishes from the upper and lower Orange, with many fish sharing two closely related mtDNA lineages (58 fish) (Bloomer et al. 2007). In addition, only a single divergent smallmouth conservation unit (17 fish) from the lower Orange could be distinguished from the remainder of the smallmouth and largemouth yellowfishes analysed (Bloomer et al. 2007). In contrast, the present study found 38 unique mtDNA lineages among 180 KZN yellowfish using the same DNA region (Figure 1). From the allele tree there is clear distinction between five groups of lineages. From north to south they are: Mkuze/Mfolozi, Tugela (including the Tugela, Mvoti, Mdloti and Molweni), Mbokodweni, Mkomazi and Mzimkulu/Mtamvuna. Genetic variation in the species is thus geographically highly structured and until the relationship between the five groups is fully understood they should be treated as five distinct conservation units. In addition to the variation summarized above, our analysis identified two highly divergent individuals sampled from the White Umfolozi. An analysis including the other small scaled yellowfish species surprisingly showed that these two individuals are even more distinct from the rest of the small scaled species, than what the Clanwilliam yellowfish is. Highly distinct individuals have also been identified in L. polylepis and we hope that analysis of all ~ 500 yellowfish DNA sequences generated to date will shed some light on what species these individuals represent.

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Figure 1. Allele tree based on maternally inherited mitochondrial DNA sequences generated for 180 KZN yellowfish. The tree shows the relationships among the 38 unique alleles (i.e. variants distinguished by different numbers of DNA base pair differences relative to each other). Values in parentheses indicate the number of fish that share the same variant. The analysis connects the alleles with the fewest genetic changes; the connecting lines/branches joining the alleles are drawn to scale, thus shorter branches indicate a closer genetic relationship. Five clear groups of alleles can be distinguished based on the longer branch lengths connecting them (the genetically central variant in each group is indicated in bold). These groups likely represent separate conservation units and their degree of distinction should be evaluated relative to genetic diversity within other cyprinid species and through comparison of the mtDNA results with variation in nuclear DNA genes (i.e. genes inherited from both parental lines).

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What next? Prior to publication of the KZN yellowfish results in the international literature the following actions need to be taken in early 2009: (1) More detailed analyses of the mtDNA data, (2) detailed GIS mapping of the genetic results, (3) a review of the available literature on the drainage history of the region and (4) DNA sequencing of a few representatives of each of the five lineages, as well as the two divergent individuals, for the protein coding mtDNA cytochrome b gene and two nuclear DNA genes. The latter genes will also be used to extend the Orange-Vaal analyses to enable publication of the follow-up study findings (the original pilot study results will also be integrated). In addition, we have started with the development of highly variable nuclear DNA markers that should allow a thorough assessment of gene flow processes in the small scaled yellowfishes. These markers, called microsatellites, are for example used in human forensic cases to distinguish individuals, or for parentage testing. Through this we aim to resolve the relationships among the identified historically isolated lineages, as well as to address the question of hybridization in the group (especially between the two Orange-Vaal species). Acknowledgements This research would not have been possible without the considerable effort in 2003, 2006 and 2007 by several individuals to collect samples from throughout KwaZulu-Natal. We thank R. Karssing, M. Nkosi, N. Rivers-Moore, J. Craigie, R. Arderne, A. Howell, J. Wakelin, H. Filter, H. Plank, T. Wilkinson and G. O’Brien for their invaluable contributions. We also thank the YWG and in particular Peter Arderne for initiating and coordinating the sampling effort. The research was made possible by funding support from the National Research Foundation to PB. Any opinion, findings and conclusions or recommendations expressed herein are those of the authors and therefore the NRF does not accept any liability in regard thereto. References cited Bloomer P, Bills IR, Van der Bank FH, Villet MH, Jones N & Walsh G. 2007.

Multidisciplinary investigation of differentiation and potential hybridization between two yellowfish species Labeobarbus kimberleyensis and L. aeneus from the Orange-Vaal system. YWG report. 67 pp.

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THE BIOLOGY OF SMALLMOUTH AND LARGEMOUTH YELLOWFISH IN LAKE GARIEP

B.R. Ellender* O.L.F. Weyl, H. Winker Department of Ichthyology and Fisheries Science, Rhodes University, Grahamstown 6140, South Africa.

Email:*[email protected]

This work is a synthesis of a MSc thesis and two publications:

Thesis Ellender B (2009) The impact of angling on smallmouth and largemouth yellowfish, Labeobarbus aeneus and Labeobarbus kimberleyensis, in Lake Gariep, South Africa. MSc Thesis Rhodes University. Under Review Ellender, B.R., Weyl, O.L.F., Winker, H. The biology of a large riverine cyprinid Labeobarbus aeneus in a large turbid impoundment in South Africa. in preparation J. Fish Biology. Ellender, B.R., Weyl, O.L.F., Winker, H. The biology of the largemouth yellowfish, Labeobarbus kimberleyensis in Lake Gariep, South Africa. in preparation J. Fish Biology. Synthesis This project is part of the Lake Gariep fisheries research programme, which aims to develop policy advice for the sustainable utilisation of fisheries resources. Specifically the project aimed to assess the impact of recreational and subsistence fishing on two species with high conservation priority, the smallmouth yellowfish Labeobarbus aeneus and largemouth yellowfish Labeobarbus kimberleyensis in Lake Gariep. Sampling was undertaken in the two open access fishing areas, namely: Oviston (OV) and Gariep (GD). Experimental gillnetting (5 x 45 m multi-meshed gillnets) was conducted bi-monthly between March 2007 and May 2008. All fish collected in gillnets underwent full biological analysis to determine: age and growth; length weight; maturity and population structure.

Age and growth was determined using whole otoliths. Age was validated by Marginal Zone Analysis and the mark/recapture of chemically tagged captive fish. Both methods indicated that a single growth zone was deposited annually in L. aeneus and L. kimberleyensis otoliths. The growth of L. aeneus was best described by the von Bertalanffy growth model as Lt = 481.80 (1- e-0.22(t+0.61)). Growth differed between sex, with female L. aeneus growing faster than the males. Gonadal development for L. aeneus was seasonal, with the gonadosomatic index peaking in January, revealing a distinct spawning season. The length at 50 % maturity for female L. aeneus was attained at a fork length of 354.7 mm. Natural mortality (M) was estimated at 0.55 year-1.

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From a summary of biological data on L. aeneus, the species has similar growth rates and maximum ages of other L. aeneus populations (Table 1).

Table 1 Summary of von Bertalanffy growth parameters of South African Labeobarbus aeneus populations (Weyl et al., in press). Lmat = length at maturity; A mat = age at maturity; ω = KL∞; VGBF = Von Bertalanffy growth function; L∞ = asymptotic length; K = Brody growth coefficient; t0 = age at zero length; M = Natural mortality; 1Koch, (1975); 2Hamman, (1981); 3This study; 4Weyl et al., (in press); 5Mulder, (1973); 6Tómasson, (1983); 7Straub, (1972); 8Richardson et al., (in press).

Maturity VBGF Parameters Natural mortality Location Lmat Amat L∞ K t0 M Males Boskop Reservoir1 - - 345 0.195 -0.07 - Lake Gariep2 210 3 676 0.110 -0.09 - Lake Gariep3 231 3 398 0.330 -0.34 0.46 year-1 Glen Melville Reservoir4 297 4 407 0.193 -0.20 - Great Fish River4 247 3 374 0.403 -0.06 - Vaal River5 280 4 1115 0.059 -0.48 - Lake van der Kloof 6 - 3 603 0.190 0.52 - Females Boskop Reservoir1 - - 1560 0.031 -0.53 - Lake Gariep2 310 5 684 0.120 -0.20 - Lake Gariep3 354 5 491 0.236 -0.29 0.55 year-1 Glen Melville Reservoir4 327 6 13259 0.001 -6.85 - Great Fish River4 333 4 516 0.235 -0.15 - Vaal River5 340 5 1221 0.051 -0.51 - Lake van der Kloof 6 300 4 710 0.160 0.47 - Combined sexes Glen Melville Reservoir4 - - 650 0.066 -4.23 0.96 year-1 Barberspan Reservoir7 - - 1281 0.036 -1.15 - Xonxa Reservoir8 - - 276 0.250 -0.63 0.30 year-1 Lake van der Kloof5 - - 465 0.234 0.369 - Great Fish River4 - - 498 0.230 -0.37 0.56 year-1 Vaal River5 - - 765 0.150 0.11 -

Labeobarbus aeneus cpue two regions of the lake was seasonal. In the middle basin cpue was highest in winter and lowest in summer, while the opposite was true for dam wall region. The high summer cpue near the lake wall was concurrent with peak gonadal development. This indicates that the Lake Gariep L. aeneus may not undergo a spawning migration up the inflowing rivers, but congregate near the lake wall. This evidence suggests that L. aeneus may spawn in the lake.

The abundance and catch rates of L. aeneus in Lake Gariep has increased from early fishery surveys on Lake Gariep just after impoundment. The species is now the second most dominant fish in Lake Gariep gillnet catches.

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The growth of L. kimberleyensis was described by the von Bertalanffy growth model as Lt = 763.22 (1- e-0.11(t+0.63)) and the oldest fish was 17 years old. Only 6 mature female and 15 mature male L. kimberleyensis were recorded during the study period. The smallest mature female was a 390 mm FL stage four female and the earliest recorded mature male was a 337 mm FL, ripe running male.

Table 2 Summary of South African von Bertalanffy growth parameters for L. kimberleyensis (1Mulder, 1973; 2 Hamman, 1981; 3 Tómasson, 1983; 4This study).

Location Maturity VBGF Parameters Lmat (minimum) L∞ K t0

Males Vaal River1 350 mm 667 mm 0.12 0.27 Lake Gariep2 400 mm 1108 mm 0.06 0.08 Lake van der Kloof3 - 541 mm 0.17 0.20Females Vaal River1 460 mm 1039 mm 0.12 0.27 Lake Gariep2 440 mm 1141 mm 0.06 0.20 Lake van der Kloof3 - 614 mm 0.14 0.22 Both Sexes Vaal River1 - - - -Lake Gariep2 - - - -Lake van der Kloof3 - 1073 mm 0.09 0.48 This study4 390 mm 763 mm 0.118 -0.634

In conclusion, yellowfish are fully established in the dam. Both species are slow growing and long lived, with the oldest recorded smallmouth being 12 years and the Largemouth 17 years (not full size structure). In the Orange River, smallmouths were older than recorded from the lake (52 cm FL female = 14 years). Maturity is delayed and L. aeneus has medium rates of natural mortality. These species are likely to have relatively stable population sizes but will take a long time to rebuild if overfished. References

Hamman, K.C.D., 1981. Aspekte van die bevolkingsdinamika van die Hendrik Verwoerddam met verwysing na die ontwikkeling van ‘n visserybestuursplan. Rand Afrikaans University, South Africa.

Koch, B.S., 1975. ’n Visekologiese ondersoek van Boskop Dam, Wes Transvaal, met spesiale verwysing na die bevolkingsdigtheid van Labeo capensis en Labeo umbratus in verhouding tot die ander hengelvissoorte. Rand Afrikaans University, South Africa.

Mulder, P.F.S., 1973. Aspects of the ecology of Barbus kimberleyensis and Barbus holubi in the Vaal River. Zoologica Africana 8, 15-24.

Richardson, T.J., Booth, A.J., Weyl, O.L.F., in press. Rapid assessment of the fishery potential of Xonxa Dam near Queenstown, South Africa. African Journal of Aquatic Science.

Straub, C.C., 1972. The value of certain morphological features in the age determination of the small mouth yellow fish Barbus holubi (Steindachner 1894). University of Potchefstroom, South Africa.

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Tómasson, T., 1983. The biology and management considerations of abundant large Cyprinids in Lake le Roux, Orange River, South Africa. Rhodes University, Grahamstown, South Africa, p. 218.

Weyl, O.L.F., Stadtlander, T., Booth, A.J., 2009. Establishment of translocated populations of smallmouth yellowfish, Labeobarbus aeneus (Pisces: Cyprinidae) in lentic and lotic habitats within the Great Fish River system, South Africa. African Zoology 44(1)

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LIKELY RESPONSE OF SMALLMOUTH YELLOWFISH POPULATIONS TO FISHERIES DEVELOPMENT

– IS THERE CAUSE FOR CONCERN IN SA DAMS?

Olaf Weyl1, Bruce Ellender, Henning Winker and Hermine Stelzhammer Department of Ichthyology and Fisheries Science, Rhodes University, 6139 Grahamstown. [email protected]

In South Africa food security, economic empowerment, tourism development, optimal economic benefit from water and poverty eradication are major national policy objectives. Government has legislated that local authorities (municipalities) are to promote local economic development. Provincial nature conservation authorities are expected to participate in this process and have been empowered to allocate licences for subsistence, commercial and recreational fishing. They are guided by the National Environmental Management Act 1998(NEMA) which emphasises issues of sustainability, biological diversity, ecosystem integrity, the precautionary principle, the use of natural resources for the national good. The potential of fisheries to create livelihood and economic opportunities is often misunderstood and as the demand for subsistence and commercial fishing rights grows there is an increasing need for informed decision making processes. Our research into the biology of smallmouth Labeobarbus aeneus and largemouth Labeobarbus kimberleyensis yellowfish on Lake Gariep has shown that they are slow growing, long lived and late maturing species with medium rates of natural mortality. These traits imply stable population sizes in unfished populations but also imply that when these fish are overfished their stocks will require a relatively long time to rebuild. We, therefore, assessed the impact of angling on smallmouth yellowfish in the 364 km2 Lake Gariep. This is South Africa’s largest inland water body, from an economic and biological perspective. We attempt to answer the question whether fisheries development on the lake would lead to socio-economic development without a compromising a typical conservation goal i.e. the maintenance of yellowfish populations at levels where the relative biomass of mature adults is at least 50% of that if they were not exploited. Characterising the current fishery Household interviews in the settlement of Venterstad (population 7000) showed that unemployment is high (66%) and 85% of households relying on social grants for cash income. Fishing is important with 57 % of all households having a member that had fished in the last year and in 25 % of households at least one family member fished weekly. Ninety five percent of households ate fish at least once a week. From on lake interviews with anglers (n=650 interviews) and direct weighing of their catches we estimate that 79 tons of fish is harvested by subsistence and recreational anglers annually. The main angling target species and the “most preferred” fish is carp Cyprinus carpio which comprises 80% of subsistence (creel survey) and recreational angler’s catches and 65 % in angling competitions. Therefore, carp is the most important food fish and has the highest perceived value for sport anglers. The latter was also supported by results from interview surveys conducted during angling competition events. Not only do yellowfishes make up a

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small portion of the catch (< 10%) but they are also caught mainly at sizes larger than maturity. Spawner biomass per recruit modeling showed that the current fishery resulted in a negligible impact on yellowfish and that the stock was in a pristine state being reduced by only 7% as a result of fishing. In comparison, the marine inshore kob and white steenbras spawner biomass are currently estimated at below 5% of pristine levels. The model also implies that shore angling could increase almost indefinitely without resulting in a depletion of the spawning stock to 50% of pristine levels. Angling has major socio-economic impacts and we estimate that there are 450 regular subsistence anglers utilizing the lake. These anglers sell their excess at R5/kg and angling is considered an important contributor to livelihoods in the area. Casual recreational anglers harvested about 30 tons/yr and competition anglers landed 7.5 tons/yr. These anglers contribute to the local economy and our questionnaire data show that competition anglers spent R525/angler/night locally which equated to a total R523 000 in assessment year. The value of fish caught by this sector to the local economy was therefore valued at was R70/kg of fish We therefore conclude that subsistence angling is important to the livelihood of the rural poor. Recreational angling creates employment in associated industries (B&B’s, restaurants, filling stations) and imports significant capital to the local economy. Both fisheries are based on the harvest of an alien species, carp, and yellowfishes make up only a small portion of the catch. Subsistence and recreational angling therefore contributes to socio-economic development without compromising conservation goals. Commercial gill net fishing Results from our experimental gill net surveys show that catch rate was dependant on mesh size. Best catch rates were obtained using a 100 mm mesh size but the catch was dominated by indigenous smallmouth yellowfish (37 %) and mudfish (48%) rather than carp (4 %). In addition, the risk of catching largemouth yellowfish Labeobarbus kimberleyensis, a protected species in the Free State, increases with mesh size and at mesh sizes larger than 144 mm, which do not target smallmouth yellowfish, 25% of the catch was largemouth yellowfish. We also showed that because of their slow growth rate and late maturity, gill net fisheries would result in a rapid depletion of the smallmouth yellowfish stock to below 50% of pristine levels. Using our experimental catch data we also conducted an economic assessment based on our experimental gill net catch data. We have conducted a financial analysis and at the current fish price of R5/kg the internal rate of return on a small operation with a realistic boat powered by a 15 Hp motor and a small vehicle (total loan R 150 000) would only be in the region of 15%. This is only marginally better than the bank lending rate and, therefore, does not constitute a viable business. It is also likely that a commercial fishery would compete directly with the subsistence fishers for market and will affect livelihoods. We conclude that a commercial gillnet fishery would be marginally viable, create few jobs, would be based on indigenous species, may compete with subsistence fishers for market and will definitely conflict with recreational anglers. The positive economic impacts of a

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commercial gill net fishery would not outweigh the negative impact on the yellowfish stocks. Given that gillnet fisheries and commercial fishing is being identified as development opportunities there is cause for concern with regard to yellowfish. Fisheries development should rather focus on developing recreational opportunities through angling or to explore alternative harvest strategies such as beach seine netting that would avoid yellowfish.

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EARLY DEVELOPMENT OF VAAL RIVER SMALLMOUTH YELLOWFISH

Daksha Naran Consultant researcher - Centre for Aquatic Research, University of Johannesburg & SAIAB, Private Bag 1015,

Grahamstown 6140. Email: [email protected])

ABSTRACT The yellowfishes are an important group of fishes within South Africa, in that they are widely used as a food source, are a targeted angling species and are widely used by biologists and ecosystem managers within South Africa as an indicator or flagship species. In order to ensure that we are able to conserve these fishes a detailed understanding of the life-cycle biology of these species is required. This paper describes the embryonic and early stage development of the Orange-Vaal Smallmouth yellowfish (Labeobarbus aeneus). The aim of the study is to provide a description of the embryo and larval stages of the Orange-Vaal Smallmouth yellowfish reared under controlled laboratory conditions. Individual Orange-Vaal Smallmouth yellowfish from the Gariep state fish hatchery were artificially spawned in early December 2008 and thereafter embryos were reared in aquaria to juvenile stage. Tracking early stage development of the species presents key characteristics of larval and juvenile morphology that supports the early stage identification, as well as the periods of transition particular to a species. The findings of the experiment resulted in the identification and detailed descriptions of the embryonic period and post-hatching development of the artificially spawned Orange-Vaal Smallmouth yellowfish. INTRODUCTION BACKGROUND TO EARLY DEVELOPMENT IN FISH The early development of fishes is highly dynamic, with changes in ontogenetic state often coinciding with shifts in diet, microhabitat, behaviour, performance or any combination of these (Sagnes et al., 1997; Gozlan et al., 1999). Fish develop strategies such as predator avoidance and swimming capacity earlier on during ontogeny, these characteristics also influences a young juvenile fish and/or fish larva’s ability to survive. Information and knowledge of early development, therefore, is fundamental to understanding the changing ecological requirements of a species (Baras & Nindaba, 1999; Kovac & Copp, 1999) and the factors affecting population recruitment (Houde, 1994). Morphologically, early life ontogeny in fish can be described according to developmental periods and steps (Balon, 1975, 1999; Peùnz et al., 1986), or quantitatively scaling developmental events against a selected criterion (Fuiman, 1994; Fuiman et al., 1998). Describing key developmental events of the early stages of fish life chronologically, could improve the techniques used to rear progeny during this critical period, provide comparative data, as well as provide information for addressing fisheries questions. Larval development of the yellowfish species Labeaobarbus kimberleyensis and Labebarbus aeneus have not been previously reported, despite the importance of such studies for the sustainable management and conservation of these indigenous fisheries.

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Early development is a complex process. Balinsley 1948 recognised 46 stages of fish development from unfertilised egg to stage 46 when lateral line is fully developed and morphogenesis is complete. There is much contestation concerning the early development proceeds via a series of steps or salutatory development, continuous or as inconspicuous accumulation of small changes (gradual ontogeny). Many of these theories and ideas of early stage development in fishes have been captured in the journal Environmental Biology of Fishes volume 56, 1999. Aspects of research investigated include:

• Does development proceed gradually over time, or by a series of relatively distinct steps?

• Does the larval period begin with hatching or with the onset of exogenous feeding? Although, cognisance of the above mentioned, theoretical concepts to the understanding of early development research was considered. The aim of this research project was to successfully rear embryos to juvenile stage. The purpose of the present early life history work is also to support ongoing yellowfish biological and ecological research projects that are being undertaken by the University of Johannesburg and other collaborators. AIM AND OBJECTIVES OF THE STUDY The aim of the study is to provide a description of the embryo and larval stages of the Orange-Vaal Smallmouth yellowfish reared under controlled laboratory conditions. Systematic collection and analysis of larval and early stage juvenile fishes is therefore an approach to resolve the early stage species identification. In order to reach this aim the following objectives have been established:

• Provide species specific early development characters and features which can be used to confirm the species identity. These determinations will contribute towards the identification of the larval and juvenile fish field based collections.

• Behaviour observation of larvae and early stage juveniles will allow for speculation with regard to their distribution, ecological and environmental requirements, including habitat and niche preferences and will assist with the sampling approaches for early stage fish.

• Provide a comparative analysis of the above objective for L. aeneus and L. kimberleyensis

METHODS EARLY FISH DEVELOPMENT The artificial spawning and larval studies were structured to run concurrently, in that the results of artificially induced fish were used to support the larval development component. This was undertaken according to the following steps:

1. Orange-Vaal Smallmouth yellowfish embryos were obtained from an artificial spawning experiment conducted at Gariep Dam Hatchery, from 6-7 December 2008. Commercially obtained Aquaspawn®, was dispensed at the recommended dosage of 0.5ml/kg to broodstock. The broodstock were estimated to be between 2 and 4kg, thus 1-2ml was administered to each fish. Aquaspawn® was injected intramuscularly, below the dorsal fin. The fish were anesthetised in a solution of 0.2ml/l of 2-phenoxyethanol until they were placid, prior to handling procedures.

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2. Ripe running fish were hand stripped, the eggs and sperm were collected in a plastic bowl and activated using aquarium water in which the embryos were to be incubated. The fertilized eggs were suspended on hatching trays in well aerated aquaria at approximately 22°C.

3. 36 hours after activation, embryos were transferred from the Gariep Dam State Hatchery to glass aquaria kept at the Department of Ichthyology and Fisheries Sciences facility (DIFS). During the transfer embryos were kept in a plastic bag, and chilled to reduce mortality. During the 5 hour journey water temperature dropped to 15°C.

4. Embryos were incubated on plastic mesh hatching trays in glass aquaria, kept at the Department of Ichthyology and Fisheries Sciences facility (DIFS). The aquaria were aerated, and initially the embryos were incubated in Gariep dam water. Thereafter, weekly water (10 - 20l) changes were done using previously collected green water. Water temperature was 17°C -20°C throughout the experiment.

Examination of specimens Embryo development was observed and photographed following the schedule:

1. two and four, (six hour intervals for a period of 2 weeks after activation) 2. 24 hour (3-4 weeks after activation) 3. two day intervals (1-4 months after activation )

Further observations were made using a stereomicroscope Leica E24D and Wild Heerburgg fitted with a digital camera (Olympus 4.1 megapixel). Observations were made under a range of magnifications and larval measurement were taken using an objective micrometer. Fertilised embryos were siphoned, and collected in a Petri dish for observations. Sub-samples of embryos, larval to early stage juveniles were collected as vouchers, for deposition at SAIAB. The samples were fixed in 99% wt/vol buffered ethanol, as well as 4% buffered formalin.

RESULTS AND DISCUSSION Embryo transfer The impact of transferring embryos to a different locality, the transfer approach and conditions served to provide insight into how embryos survive. Several factors contributed to the operation’s success. At the onset the transfer process was designed to keep the variables at a minimum. The embryos were transported with adherence to the same water chemical condition as that used for spawning and activation. The plastic bags were filled with fresh water tapped directly from the dam, and saturated with pure oxygen. The bags were sealed and placed in a polystyrene box to minimize temperature fluctuation. To facilitate transport a sealed bag of ice, wrapped in a towel, was placed in the polystyrene box. After the 5 hour journey embryos were transferred to glass aquaria filled with Gariep river water. Transported embryos at 15°C were acclimatised to 19°C and 23°C, into 2 separate aquaria, over a period of 3 hours. The overall effect of the reduction in temperature was to slow the rate of development down, consequently the embryos hatching period was extended by 24-30 hours.

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Larval and juvenile rearing Thereafter the developing embryos were generally kept in water temperature ranging between 19°C to 23°C. The embryos, larvae and juveniles were kept under a fluorescent light, with approximately 12-14 hours of darkness. After hatching larvae were fed newly hatched brine shrimp, Artemia salina nauptilii in excess quantities twice a day. Older larvae and juveniles were weaned on a diet of fish flakes and chironomid larvae (blood worms). Fertilised embryos Fertilised eggs are negatively buoyant and slightly adhesive to the glass and mesh trays. Adhesiveness was lost after a few minutes. Embryo period This period consists of five key steps: activation; cleavage; epiboly; organogenesis; onset of blood circulation. Embryo phase (E1-E5 respectively) are described below. The time from activation to hatching lasted between 84 h 30 min and 153 h (3.5days – 6 days). L. aeneus eggs are spherical pale yellow and are negatively buoyant. E-1, Activation phase Eggs and sperm were gently mixed using a bird feather. After a few seconds the fertilization was activated by adding river water to the stripped eggs and sperm. After activation the eggs become adhesive to the tray and to each other Shortly after activation the egg begins to swell. Step E1, activation, began at 0.58h, 7 December 2008. During this step the eggs rapidly took in water and increased in size until the diameter measured between 0.22 mm and 0.24 mm The swelling of the eggs also caused them to change from their initial spherical form, becoming slightly oval in shape and flattened on the surfaces that adhered to other eggs in the strip. During this step the perivitelline space was created E-2, Cleavage phase Onset on certain initial steps of the cleavage phase was not observed due to technical problems. The result of cleavage phase is the blastula formation, where cells divide and begin to surround the yolk. The phase ends with the descending blastula to encircle the yolk. This marks the onset of the next phase. E-3, Epiboly, had commenced by 20h00 with the onset of the cell layer migrating across the yolk surface. The morula became progressively smaller and more flattened in shape and by 07 h 35 min the embryonic shield, which surrounded 75% of the circumference of the yolk, was evident. At this stage, the cell layer covered approximately three-quarters of the yolk surface. Closure of the germ ring occurred around 31 hours (figure 1) E-4, Organogenesis began with the development of the neural plate and cephalization of the embryo. This is a complex step where the optic vesicle becomes evident in the majority, myomeres begin to form. There is separation of the caudal section from the yolk, which started to divide into a large anterior section and a more slender posterior section. The extension of the tail region has the effect of stretching the yolk sac, where the posterior section is more slender than the anterior section.

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E5, Circulation, Onset of blood circulation, had developed with the first muscular contraction being observed, the process ended with hatching. The brain is visible, pigment was first visible in the eyes. At 4-6 days the initial formation of the otic vesicles and the rudimentary buds of the pectoral fins were first evident. At this stage otoliths were first visible and the blood began to take on a red colour. The pectoral lobes are evident and began to move. This step gives way to the onset of the free embryo phase (figure 2). Note: Certain events in the E3- E5 were not observed directly due to transit, and the estimation of these events can be provided using photographic records. Post-hatching development After hatching, free embryos and larvae in the aquarium were subjected to temperatures ranging between 19°C.and 22°C. These two periods of development consisted of one free embryo step and five larval steps. The time scale from activation to the end of the larva period, when the first larvae became juveniles, lasted 69-73 days. The extended periods of development could have been due to the lower water temperature and the twice a day feeding regime. Free embryo phase E-6, free embryo, began with hatching and ended with the onset of exogenous feeding. Hatching occurred between 84 h 30 minutes and 153 hrs, on the 10-12 December 2008, 4 to 6 days after activation. Post hatched embryos were 7.2 mm long with a substantial yolk reserve. The following features were also evident with cephalisation; oral region with a pore, lens and choroid areas, heart, otoliths, notochord which is surrounded by myomeres and an anal pore. Post-hatching, free embryos generally displayed varying degrees of swimming capability. The earliest embryos to hatch were only able to perform sudden bursts of activity and appeared to be able to swim a few centimetres from the bottom before sinking again. Those embryos that hatched later, however, were able to perform more sustained swimming and were soon able to swim to the surface. Upon hatching, the embryos were with the head bent down over the yolk and generally un-pigmented. During this step various developmental processes were taking place, including the jaw and gill structures, the gradual straightening of the head and the formation of the chambers of the swimbladder and fin fold transition to fin rays (figure 3a & b). Larval period Larva, stage 1: The onset of L1 step was characterized by the onset of exogenous feeding and ended with the onset of flexion of the urostyle and the switch to purely exogenous nutrition. The first free embryos reached this step after 2 days. The ability of L1 larvae to open their mouths corresponded with the ability to swim to the surface and begin gulping air to inflate the anterior and posterior chamber of the swimbladder. This consequently resulted in the ingestion of ‘air’ and the mouth becoming functional. The opening of the mouth also coincided with the onset of branchial respiration and the functionality of the gills. At the beginning of L1, larvae still had a large pear-shaped yolk sac and the mouth remained in a sub-terminal position. A few days later (fifth and sixth day post hatching), the head was straight and the body took on a yellow colouration. Melanophores also became evident on

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the head, heart region and the ventro-visceral and medio-ventral lines with faint dashes of pigment just becoming evident on the lateral line. As this step progressed, these pigments became more obvious. By day 9-11, the mouths had migrated into terminal positions and Artemia nauplii were first found in the gut. At this stage, only a small amount of yolk reserves remained to be absorbed. Young larval stage 2 This step, started from the 15th December 2008, the ninth day after activation, with the switch to purely exogenous nutrition and the beginning of flexion of the urostyle. This step proceeded until the onset of inflation of the anterior chamber of the swimbladder. By 19 December, rays were beginning to develop below the urostyle within the caudal finfold. From the beginning of this step, melanophores became distributed on the head, lips and opercula. Pigment also became evident above the notochord. After 16 days the dorsal finfold was showing the first signs of differentiation and later starting to form in both the dorsal and anal fins. The onset of this step also corresponded with a clear shift in behaviour. While the remaining L1 larvae were still swimming at the surface, L2 larvae were forming a shoal between 5 and 10 cm from the bottom of the tank. The larvae were 9.7mm in length (figure 4). Intermediate larval stage 3 By day 16-20, air was first evident in the anterior chamber of the swimbladder. This signified the beginning of larva step L3 with the end of this step indicated by the dorsal finfold no longer being connected to the dorsal fin. By day 22, flexion was complete and the caudal fin was forked and almost fully developed. By now pigment was well developed both above and below the notochord and rudiments of the pelvic fins were first evident. During this step the mouth began to migrate towards the sub terminal position. Feeding is exogenous (figure 5). Older larval, stage 4 By day 23- 28 the dorsal finfold first became separated from the dorsal fin, indicating the beginning of larva step L4. By now all individuals had pelvic buds present and rays were forming in the pectoral fins. At the end of this stage all fins except for the pelvic fins were fully formed and only a small amount of pelvic finfold remained. The mouth was almost in the final, sub terminal position. The scales were evident just below the lateral line. Young juvenile, Larval stage 5 Complete disappearance of the finfold, indicating the beginning of larva step L5 and completion of fin formation, was first evident. The mouth was now in its final, sub terminal to inferior position. Scales were first evident just below the lateral line. Juvenile period The first fully scaled fish, with the lateral line formed, were observed in mid to late January. The transition from larvae to young juvenile is completed with the disappearance of the fin fold and the ray formations in the fins. The development of the scales, with full coverage over the body, indicates the transition from larvae to juveniles. Juveniles are not quite silvery, but rather well pigmented. Going forward there are other features that can be quantitatively determined to facilitate the larval early development work undertaken in this project. These are as follows:

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Myomeres In some instances reliable separation between species is only possible by counting the numbers of myomeres or muscle bands. Myomeres can be separated into pre-anal and post-anal groups. The larval fish are sufficiently transparent for the myomeres to be readily visible. Post anal myomeres – start with the first muscle band that lies entirely within the caudal section of the body, ie posterior to the anus and anterior to the urostyle. Pre anal myomeres are in the trunk region anterior to the anus and ending just behind the head. Relative body dimensions Caudal trunk ratio: Trunk region / caudal region – includes head, and is important for distinguishing percids from cyprinid and can assist in distinguishing certain species of cyprinids. After stage 5, cyprinids do not possess teeth inside the mouth. Instead, at the back of the pharyngeal cavity, cyprinids have developed a pair of pharyngeal bones armed with projections – resembling “teeth” that crush and chew food as it passes to the back of the pharynx. Adult cyprinid can be identified by the arrangement, and number of teeth. Eye diameter Inter ocular distance and the snout length, ratios of relative measurements of eye diameter, inter ocular distance and the length of snout are useful characters, that can be measured using the eyepiece graticule. CONCLUSIONS The current project represents work that is being undertaken using a systematic approach, which serves to give value to early development studies, which has not previously conducted with these objectives. The project is contributing to the state of knowledge of the larval and juvenile stage freshwater fishes as well as providing insight into the early stage fish behaviours which can assist with ecological interpretation and serve to refine sampling strategies. Furthermore, the project is catering for the parameters to identification of early stage embryo and larvae with characteristics such as

– Stages /Period – Length at hatching – Length at absorption of yolk – Pigment presence and pattern – Myomere ratios – Morphological ratios

Such knowledge and data have not previously been used to describe early stage freshwater fishes in South Africa

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REFERENCES Balon, E. K. (1971). The intervals of early fish development and their terminology.

Vestnik Ceskoslovenske Spolecnosti Zoologicke 35, 1–8. Balon, E. K. (1979). The theory of saltation and its application in the ontogeny of fishes:

steps and thresholds. Environmental Biology of Fishes 4, 97–101. Baras & Nindaba, 1999, Seasonal and diel utilization of inshore microhabitats by larvae and

juveniles of Leuciscus cephalus and Leuciscus leuciscus. Environmental Biology of Fishes 56, 183–197

Gozlan et al., 1999 Early development of the sofie, Chondrostoma toxostoma. Environmental Biology of Fishes 56, 67–77.

Houde 1994 Differences between marine and freshwater fish larvae: implications for recruitment. ICES Journal of Marine Science 51, 91–97.

Kovac & Copp, 1999 Prelude: looking at early development of fishes. Environmental Biology of Fishes 56, 7–14.

Pinder, A. C. (2001). Keys to larval and juvenile stages of coarse fishes from fresh waters in the British Isles. Scientific Publication No. 60. Ambleside: Freshwater Biological Association.

Sagnes et al., 1997 Shifts in morphometrics and their relation to hydrodynamic potential and habitat use during grayling ontogenesis. Journal of Fish Biology 50, 846–858.

ACKNOWLEDGEMENTS The early development of smallmouth yellowfish was a collaborative initiative with various partners sharing expertise, experience and resources. The following organisations and individuals within the organisations are thanked for their valuable contributions in realising the goals of this component. Mr Gordon O’ Brien & colleagues (Centre for Aquatic Research, Zoology Department, University of Johannesburg), Mr Martin Davies (Department of Ichthyology and Fisheries Sciences, Rhodes University), Staff and management of Elgro River Lodge, Prof. A. Hodgson, Mrs Shirley Pinchuck and Mr Mervin Randall (Electron Microscopy Unit, Rhodes University), Fisheries staff of Gariep State Hatchery, Mr N James (Rivendell Hatchery), Prof. M. Hill (Zoology Department, Rhodes University) Mr Stephan Van Der Walt (Rivers of Life, Randfontein, Johannesburg), Water Research Commission. Selected photographs of the developing embryo, larvae and juvenile stages of smallmouth yellowfish are on the following 4 pages.

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Selected photographs of the developing embryo, larvae and juvenile stages of small mouth yellowfish

Figure 1 Embryo stage 3, Epiboly, onset of the cell layer migrating across the yolk surface

Figure 2. Embryo stage 5, Circulation, Onset of blood circulation

10/12/08, 09h35

OOppttiicc lleennss

Otoliths

Notocord

Myomeres/myoseptum

Onset of circulationStage E5

07/12/08, 23h11

Descending blastoderm, encircling yolk

Epiboly Stage E3

19mm

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Figure 3a. Free embryo phase began with hatching and ended with the onset of exogenous feeding

Figure 3b. Free embryo phase began with hatching and ended with the onset of exogenous feeding

10/12/08, 11h35

Myomeres

Notocord

Finfold

Cephalisation

Heart Lens,Choroid fissure, Oral pore

Yolk

Free embryo -Larval Stage 1

Truck region

Anal pore

Circulatory pathways

Free embryo Larval Stage 1

10/12/08, 11h35

Caudal region

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Figure 4.Young larvae stage 2, the switch to purely exogenous nutrition and the beginning of flexion of the urostyle

17/12/08, 10h00

Pectoral lobes

Gills & operculum

Swim bladder

Onset of pigmentation

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Figure 5. Intermediate larvae stage 3, flexion was complete and the caudal fin was forked and almost fully developed

Figure 6. Young juvenile complete disappearance of the finfolds, and fish in juvenile pigment dress.

19/12/09, 11h00

Dorsal lobe

Urostyle

Intermediate larvae, Stage 3

16/02/09, 08h30

Juvenile stage – melanophore extent

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BODY SHAPE CHANGES AND ACCOMPANYING HABITAT SHIFTS: OBSERVATIONS IN THE LIFE CYCLE OF LOWVELD LARGESCALE

YELLOWFISH, LABEOBARBUS MAREQUENSIS, IN THE LUVUVHU RIVER CATCHMENT.

P.SO. Fouché1, W. Vlok 2 and A. Jooste3 1 Department of ,Zoology, University of Venda, 2BioAssets, Polokwane; 3 Department of Biodiversity

(Zoology), University of Limpopo. 1Email: [email protected] Abstract As part of a habitat utilization study specimens of L. marequensis were collected in previously identified biotopes at eleven sites in the Luvuvhu River and selected tributaries during 2006 and 2007. The morphometric characters of each specimen collected were measured and analysed using truss analyses. The biotopes at site each were delineated and mapped in detail. During each survey the physical characters, which included the water velocity, depth and substrate composition of each biotope were determined and recorded. Analyses of the body length to body mass relationship showed that nine stanzas or growth phases could be distinguished in the life cycle of the species. Statistical analyses showed that each of these stanzas had distinctly different morphometric characters that could be regarded as ontogenetic changes. A distinct pattern of habitat utilization by the stanzas in the biotopes in which the specimens were collected was identified. 1. Introduction Broader habitat characteristics define the tolerance limits, and consequently the distribution of fish species, in a river (Gaigher, 1973). Variation on a finer scale within a river reach leads to the formation of different micro-habitats within habitats (Gatz, 1981) and differences in water velocity and substrate size inter alia forms part of this variation. The size, shape, swimming ability and feeding strategy of a species defines its suitability to a micro-habitat. The micro-habitat utilized by the different life history stages differs and is often a reflection of the evolutionary history. While broader habitat characteristics do not directly lead to morphological adaptations, Wood and Bain (1995) were of the opinion that morphological differences could be related micro-habitat characteristics. In addition to micro-habitat adaptation, the idea of associating the morphology of a species with its niche is an old and persistent one. Already in 1980 Bock (in Gatz, 1981) proposed equating the niche of an organism to the “sum of the biological roles of its morphological features and the selective forces that operate on those roles”. Since previous studies by Gaigher (1969) and Fouché et al., (2005) indicated that while the large specimens of the Lowveld largescale yellowfish, Labeobarbus marequensis, were usually present in deep, slow-flowing water, the smaller specimens occurred in fast-flowing shallow water it was postulated that differences in the biotope preferences of the various size classes of L. marequensis might exist.

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It was hypothesized that morphological differences between various size classes or growth phases of L. marequensis existed and that these differences were related to the characteristics of the preferred biotopes and to biological aspects such as feeding. The aim of this study was to determine the morphological characteristics of the various size classes of L. marequensis and to relate that to habitat. i.e. biotope, preference. 2. Materials and methods 2.1 Site selection, delineation and mapping. Sites where L. marequensis historically occur were selected in the Luvuvhu River and tributaries. Care was taken to ensure that each site was representative of the specific river reach in which it occurred and that each site had a well defined pool-riffle-sequence. Areas belonging to the different velocity-depth classes (Kleynhans, 2007) were identified at each site and each area was then treated as a separate micro-habitat. In each micro-habitat the substrate was identified and classified as bedrock, boulder, cobble, pebble, gravel, sand or sediment according to the prescriptions of Rowntree and Wadeson (2000). Because velocity-depth classes and substrate composition was used in combination it was decided to use the term “biotope” rather than micro-habitat (Paxton, 2004). In each biotope the depth was then measured at four randomly selected points. At these points the velocity was measured in ms-1 using a Pasco velocity meter. A sketch map to illustrate the site heterogeneity was then drawn on which the biotopes were delineated and numbered. 2.2 Collection and measurement of the fish specimens. In fast-deep and fast-shallow biotopes the fish were electro-narcotized and collected with scoop nets. In the slow-deep and slow–shallow biotopes, that were clear of snags, a small seine net was used. A pole-seine was used in the small pools, backwaters and in particular where sampling had to be done under and amongst vegetation. All the specimens collected were identified using the key proposed by Skelton (2001). Care was taken to keep specimens from each biotope separate until the fork lengths and masses were determined. The fork length of the specimens collected was measured to the nearest millimetre and the mass to the nearest milligram. 2.3 Length-mass relationship. To establish the length-mass relationship a regression analyses was performed after which trend line was fitted to resulting scatter plot. To determine whether stanzas could be identified the slope of the trend line at the fork length mid-point of each 10mm interval fork length class was determined and compared. 2.4 Morphometrics Morphometric data of the attributes related to the feeding and habitat preference categories (Appendix 1) were measured and recorded. Measurements consisted of a combination of the truss measurement method described by Wood and Bain (1995) and physical measurements using calipers and string. For the truss measurements the specimen was placed on water-resistant paper and the selected “landmark locations” (Figure 1) marked on the paper with pin pricks. The distances between selected land marks were measured and recorded on a data sheet. These measurements and the consequent calculations are shown appendix 2.

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Figure 1: The location of the truss landmarks used for morphometric calculations (Adapted from Wood and Bain, 1995) 2.5 Statistical analyses of the habitat preference of the species.

To investigate the habitat preference of the stanzas the data analyses focused on the local scale i.e. the biotopes. Non-metric multi-dimensional scaling (MDS) was used to display the unconstrained relationships between fish sizes and the biotopes. An attempt was also made to classify the biotope types using hierarchical agglomerative cluster analysis with group average linking in Primer v.6 (Clarke & Ainsworth, 1993). The robustness of the groups identified was tested by randomly permuting the similarity matrix that is used to construct the cluster classification. 3. Results 3.1 The selected sites and biotope identification and mapping. Eleven sites were surveyed in the Luvuvhu River and its tributaries during 2006 and 2007 (Figure 2). At each of the sites the biotopes were identified and mapped. Figure 2 is an example of the sketch maps drawn at each site. 3.2 The fork length: mass relationship and the observed stanzas. As is the case in most fish the length mass relationship is an indication of allometric growth (M = cLn, where M is the mass, L the length and c and constants). Regression analyses of the length mass relationship of L. marequensis indicated that a power or multiplicative trend line, with the formula M = 0,023L3,0575, fits best with an R-squared

51


Figure 2: The selected sites in the Luvuvhu River catchment.

52


1.11.2

1.3

1.5

1.4

1.6

60m

25m

X

X

X

X

X

X

X

X

X

XX

XX

X

X

X

X

X

Figure 2: Sketch map of the site at the Gauging weir (Site 1) in the Luvuvhu River. value of 0,9876 (Figure 4). This type of trend line is typical of the larger cyprinids (Fouché, 1995; Hamman, 1974). Inflection points were visually identified on the trend line and the slope at each point was calculated and from the observed trends (Table 1) nine possible growth phases or stanzas were identified. Where stanza 1 consisted of specimens that were less than 50mm in length the boundaries of the other stanzas are: stanza 2 - 51 to 80mm, stanza 3 - 81 to 100mm, stanza 4 - 101 to 120mm, stanza 5 - 121 to 150mm, stanza 6 – 151 to 200mm, stanza 7 - 201 to 250mm, stanza 8 - 251 to 320mm. Stanza 9 consisted of specimens longer than 320mm.

53


R2 = 0.9868

0

100

200

300

400

500

600

700

800

900

1000

0 50 100 150 200 250 300 350 400

Fork length (mm)

Mas

s ( g

)

Figure 3: Regression analyses of the length: mass relationship of L. marequensis collected from the Luvuvhu River. Table 1: Calculation of the observed inclines at the inflection points observed in the fitted exponential trend line in the L. marequensis length:mass relationship.

Average fork length at inflection point.

(mm)

Average mass at

inflection point (g)

Increase in X-axis

value

Increase in Y-axis

value.

Calculated slope of fitted trend

line 44 0,8 56 2.52 15 1,72 0.1147 80 7.98 24 5.46 0.2275 102 15.70 22 7.72 0.3509 131 46.75 29 31.05 1.0707 151 64.60 20 17.85 0.8925 175 106.32 24 41.72 1.7383 204 145.00 29 38.68 1.3338 228 240.00 24 95.00 3.9583 253 320.00 25 80.00 3.2000 275 405.00 22 85.00 3.8636 300 505.00 25 100.00 4.0000 325 530.00 25 30.00 1.2000

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3.3 Morphometric characters of the stanzas. As could be expected values of the measured and calculated attributes changed as the species grew with most attributes increasing as the fork length increased. It was therefore decided, with the exception of the caudal fin aspect ratio, to rather express all the values as a ratio of the fork length of the specimen. Table 2 shows that the relative eye diameter and relative mouth width, which both are associated to feeding, decreased as the species increased in fork length. This was however not the case with the relative head length that increased as the fish increased in size. Statistical analyses showed that with regard to the eye diameter the difference between all stanzas were significantly different (p = 0.05). Table 3 shows the changes in the relative morphological features related to habitat preference observed between the stanzas. In figure 4 these changes are graphically illustrated and it is shown that while some aspects increase others either decrease or remain reasonably constant. Statistical analyses showed that difference between the stanzas were significantly different (p = 0.05) in the majority of the aspects. In table 4 the changes in the aspect ratio of the caudal fin should be noted as it is low in the first two stanzas, large in the next four stanzas and again smaller in the last three. Table 2: Average of the relative morphological features related to feeding habits of the nine “stanzas” of L. marequensis specimens collected in the Luvuvhu River. (Standard deviations in parentheses). Fork length classes N Relative eye

diameter ED:FL

Relative mouth width

MW:FL

Relative head length HL:FL

< 50 15 0.079 (0.01) 0.080 (0.01) 0.218 (0.04)51 – 80 86 0.067 (0.01) 0.071 (0.01) 0.269 (0.19)81 – 100 85 0.064 (0.01) 0.070 (0.01) 0.223 (0.02)101 – 120 83 0.059 (0.006) 0.068 (0.005) 0.205 (0.02)121 – 150 91 0.053 (0.008) 0.066 (0.009) 0.197 (0.08)151 – 200 31 0.049 (0.006) 0.069 (0.009) 0.187 (0.02)201 – 250 10 0.040 (0.005) 0.053 (0.03) 0.163 (0.04)251 – 320 16 0.037 (0.003) 0.067 (0.01) 0.188 (0.02)

> 321 11 0.033 (0.003) 0.062 (0.01) 0.176 (0.03)

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Table 3: Average of the relative calculated morphological features related to habitat preference of the nine “stanzas” of L. marequensis specimens collected in the Luvuvhu River. (Standard deviations in parentheses).

Fork length classes (mm)

n

Relative body depth

BD:FL

Relative body width

BW:FL

Relative caudal

fin surface

area CFA:FL

Relative caudal span

CS:FL

Relative peduncle

length

RPL

Relative caudal width

RCD

Relative dorsal

fin area

DFA:FL

Relative pectoral fin area

PCA:FL

Relative pelvic

fin area

PVA:FL

< 50 15 0.301 (0.04)

0.124 (0.01)

1.430 (0.32)

0.287 (0.04)

0.195 (0.03)

0.122 (0.03)

0.465 (0.13)

0.300 (0.10)

0.057 (0.03)

51 – 80 86 0.241 (0.03)

0.202 (0.04)

2.118 (0.32)

0.262 (0.04)

0.209 (0.01)

0.120 (0.01)

0.839 (0.21)

0.674 (0.32)

0.450 (0.20)

81 - 100 85

0.239 (0.02)

0.231 (0.02)

2.746 (0.39)

0.269 (0.03)

0.209 (0.02)

0.119 (0.02)

1.157 (0.29)

1.080 (0.27)

0.639 (0.11)

101 - 120 83

0.259 (0.03)

0.231 (0.03)

3.294 (0.34)

0.283 (0.04)

0.207 (0.02)

0.119 (0.01)

1.388 (0.53)

1.012 (0.50)

0.665 (0.20)

121 - 150 91

0.280 (0.04)

0.216 (0.05)

4.002 (0.60)

0.294 (0.04)

0.219 (0.02)

0.124 (0.02)

1.764 (0.62)

1.171 (0.67)

0.621 (0.39)

151 - 200 31

0.287 (0.03)

0.197 (0.07)

5.116 (0.75)

0.304 (0.03)

0.217 (0.03)

0.126 (0.01)

2.086 (0.91)

1.296 (0.54)

0.779 (0.45)

201 - 250 10

0.302 (0.03)

0.183 (0.05)

6.778 (1.02)

0,311 (0.03)

0.204 (0.02)

0.126 (0.01)

3.101 (0.82)

1.259 (0.33)

0.650 (0.48)

251 - 320 16

0.291 (0.03)

0.188 (0.05)

8.264 (1.68)

0.299 (0.03)

0.219 (0.02)

0.132 (0.01)

4.558 (1.68)

2.140 (0.80)

1.422 (0.66)

> 321 11 0.285 (0.03)

0.178 (0.06)

9.629 (1.59)

0.293 (0.02)

0.208 (0.02)

0.120 (0.01)

5.271 (1.41)

2.545 (0.95)

1.218 (0.84)

Table 4: Average of the calculated morphometric characters of the nine “stanzas” of L. marequensis specimens collected in the Luvuvhu River. (Standard eviations in parentheses).

Fork length classes

N Caudal fin aspect

ratio

Caudal fin surface area

Pectoral fin surface area

Pelvic fin surface area

< 50 15 2.02 (0.33) 67.6 (14.21) 21.36 (29.35) 2.83 (1.42) 51 - 80 86 1.95 (0.43) 150.66 (35.32) 48.04(25.66) 31.94 (15.34) 81 - 100 85 2.28 (0.44) 249.88 (45.44) 98.35 (27.08) 58.02 (11.72) 101 - 120 83 2.1 (0.27) 362.12 (47.15) 123.06 (38.3) 72.64 (21.72) 121 - 150 91 2.3 (0.16) 543.86(101.79) 160.04 (93.7) 84.58 (55.28) 151 - 200 31 2.1 (0.29) 874.85 (188.4) 212.79 (93.5) 139.05 (100.79) 201 - 250 10 2.04 (0.24) 1514.3 (324.08) 279.05 (67.9) 154.77 (123.27) 251 - 320 16 2.01 (0.36) 2418.51 (598.2) 621.8 (22.69) 417.63 (202.51)

> 321 11 2.01 (0,35) 3443.27 (852.3) 908.7 (392.8) 436.24 (304.77)

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0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

1 2 3 4 5 6 7 8 9 10

Fork length classes

Avr

\era

ge o

f rel

ativ

e m

orph

olog

ical

feat

ures

Relative body depth

Relative body w idth

Relative caudal peduncle span

Relative caudal peduncle length

Relative caudal peduncle w idth

Figure 4: A graphical illustration of the changes in the averages of five of the relative calculated morphological features of the nine stanzas of L. marequensis collected in the Luvuvhu River.

Figure 5: Hierarchical agglomerative cluster analysis based on group average linking for all biotopes.

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3.4 Habitat utilization by the stanzas. Cluster analysis, using hierarchical agglomerative methods with group average linking in Primer v.6., identified six groups of closely related biotope types in which L. marequensis were collected (Figure 5). Non-metric multi-dimensional scaling (MDS) used to display the unconstrained relationships between fish stanzas and biotopes (Figures 6 to 8) show that a definite relationship exists. However none of the biotope preferences of the stanzas was completely distinct and overlaps in varying degrees did occur. For example, while figure 6 shows that only a slight degree of overlap could be detected between stanzas 1 and 2, a comparison between figures 6 and 7 shows considerable overlap between stanzas 2 and 3. Although there is no clear cut division in the biotope:stanza relationship it can be accepted that a change in habitat preference occurs during the life cycle of the species. This change is regarded as an ontogenetic shift.

Slow – shallow

Fast-shallow

Slow-deep

Fast-deep

Figure 6: MDS ordination of stanzas 1 and 2 of L. marequensis in the biotopes.

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Figure 7: MDS ordination of stanzas 3, 4, 5 and 6 of L. marequensis in the biotopes.

59


Figure 8: MDS ordination of stanzas 7, 8 and 9 of L. marequensis in the biotopes. 4. Conclusion As is the case with many fish species and in particular the larger cyprinids, the length-mass relationship, in this species is best described by the formula M α L3. From the calculated slopes of the trend line fitted to the scatter plot of the length-mass data nine stanzas, each with its own distinctive length-mass relationship could be identified. Cyprinids have a body form that closest to what referred to by Helfman et al, (2000) as “sub-carangiform” body shape and L. marequensis is no exception. This body shape, which is characterized by a streamline body and broad V-shaped caudal fins, has the

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propulsive elements concentrated in the posterior part of the body where it is evident in the median caudal fin aspect ratio and the length of the caudal peduncle. This gives them the ability to accelerate rapidly and swim strongly. In addition to the caudal fin the “short” posteriorly placed dorsal fin makes L. marequensis more suitable for flowing rather than non-flowing habitat. According to Hildebrand (1974) sub-carangiform fish are regarded as locomotory generalists and can switch between modes, depending on what is needed For the sake of the discussion that follows and in order to compare the morphometrics of L. marequensis the concept “flowing” and in particular “fast flowing” is going to be equated with the concept “fast swimmer”. This reasoning is based on the premise that in order to survive and live in a fast flowing habitat, the specimen should be able to swim as fast as or faster than the velocity of the current. Based on its sub-carangiform body shape and with its the “short” posteriorly placed dorsal fin and the V-shaped caudal fin it is apparent that L. marequensis has a general “bauplan” most suitable to cope with a flowing water habitat rather non-flowing habitat. The caudal fin aspect ratio of the species, which ranges from just below 2 in the juveniles to 2.3 in the sub-adults falls within what can be described as median and indicates that although the fish are not as fast as the other fish that swim with the posterior trunk and tail, namely the carangiform and thunniform swimmers, they are faster than the fish that only use their fins. The calculated ratio indicates that the species do not continuously cruise (Gatz, 1981). Other aspects, such as the relative caudal peduncle length, indicate that the species is a strong swimmer. As indicated in the results, the aspect ratio of the caudal fin, which is also a relative value, initially decreased, then increased after which it again decreased. The changes in body width in particular are of note as the cross section of fish obtains its most “circular” format from stanza 3 to stanza 6 (Table 3). The “circular” cross section is typical of the sub-carangiform body and as is stated by Nikolsky (1963), Hildebrand (1974) and Helfman et al. (2000) is the classic cross section form that minimizes drag to a great extent. Based on these changes in the relative morphological aspects it would seem that initially the species does not have the ability to swim fast, or cope with fast flowing water. It then develops the ability to swim faster and this adaptation is maintained for a few stanzas. The final adaptation then seems to refer back to “slower” habitats. Ontogenetic changes in the caudal fin and related aspects were observed. Similar changes were observed in the relative caudal span and in the relative body depth and to an extent in the body width. It was therefore inferred that while the juveniles, stanzas 1 and 2, are adapted to slow flowing habitats, stanzas 3, 4, 5 and 6 which include the sub-adults and young adults, were adapted to the fast flowing habitats. The more mature adults, stanzas 7, 8 and 9, however again prefer slow flowing habitats. These inferences were vindicated and proven when the biotope preferences of stanzas were investigated. With regard to the eye diameter, mouth width and head length differences in both the actual and relative sizes were observed. Palomares and Pauly (1998) found strong relationships between food ingestion, in the various body mass classes, and morphometric characters such the aspect ratio of the caudal fin and the body depth ratio. This indicated that the change in feeding habits and diet of the various size classes could be related to the morphometry. It was shown that ontogenetic changes in both the aspect ratio of the caudal fin and the body depth also occurred in L. marequensis and it can be

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inferred that these changes can be related to changes in both the feeding habits and diet. Although this indicates that ontogenetic differences in the trophic adaptation of the species are imminent, no actual inference could be made to the actual diet make-up. In conclusion it can be accepted that the changes in morphology and the accompanying habitat preferences observed in L. marequensis would constitute a what is regarded as “ontogenetic shift” as was described by Huckins (1997). 5. Reference list CLARKE, K.R. and AINSWORTH, M. 1993. A method of linking multivariate

community structure to environmental variables. Marine Ecological Progress Series 92 :205-219.

FOUCHÉ, P.S.O. 1995. An investigation of the scale morphology and scale annulus formation and an evaluation of the scale method for age determination of Labeo umbratus (Smith) (Pisces, Cyprinidae). Unpublished M.Sc. Thesis, University of Venda. 102 pp.

FOUCHÉ, P.S.O., FOORD, S.H., POTGIETER, N. van der WAAL, B.C.W. and van REE, T. 2005. Towards an understanding of the factors affecting the biotic integrity of rivers in the Limpopo Province: Niche partitioning, habitat preference and microbiological status in rheophilic biotopes of the Luvuvhu and Mutale rivers. WRC Report no. 1197/1/05.GAIGHER, I.G. 1969. Aspekte met betrekking tot die Ekologie, Geografie en Taksonomie van Varswatervisse in die Limpopo- en Incomatiriviersisteem. Unpublished Ph.D. Thesis, Randse Afrikaanse Universiteit. 261 pp.

GAIGHER, I.G. 1973. Habitat preferences of fishes from the Limpopo River system, Transvaal and Mocambique. Koedoe 16 , 103 – 116.

HAMMAN, K.C.D. 1974. ‘n Ondersoek na die lengte, massa ouderdom en gonade ontwikkeling van die groter visspesies in die H.F. Verwoerddam. Unpublished M.Sc. Thesis, Randse Afrikaanse Universiteit. 78 pp.

GATZ, A.J. 1981. Morphologically inferred niche differentiation in stream fishes. The American Midland Naturalist 106 (1) 10 –21.

HELFMAN, G.S., COLETTE, B.B. and FACEY, D.F. 2000. The diversity of fishes. Blackwell Science Inc., Massachusetts. 528pp.

HILDEBRAND, M. 1974. Analysis of vertebrate structure. John Wiley and Sons, Inc. New York. 710pp.

HUCKINS, C.J.F. 1997. Functional linkages among morphology, feeding performance, diet and competitive ability in molluscivorous sunfish. Ecology 78 (8) : 121 – 138.

KLEYNHANS, C.J. 2007. Module D: Fish Response Assessment Index in River EcoClassification: Manual for EcoStatus Determination (version 2). 72pp.

NIKOLSKY, G.V. 1963. The Ecology of Fishes. Academic Press, New York. 351pp. PALOMARES, M.L.D. and PAULY, D. 1998. Predicting food consumption of fish

populations as functions of mortality, food type, morphometrics, temperature and salinity. Mar. Freshwater Res. 49: 447 – 453.

PAXTON, B.R. 2004. Catchment-wide movement patterns and habitat utilization of freshwater fish in rivers: Implications for dam location, design and operation. A review and methods developed for South Africa. Water Research Commission Report KV 145/04. 69pp.

ROWNTREE, K. and WADESON, R. 2000 Field manual for channel classification and condition assessment. 62 pp.

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SKELTON, P.H. 2001. A Complete Guide to the Freshwater Fishes of Southern Africa. (2nd Edition). Southern Book Publishers, Halfway House. 395pp.

WOOD, B.M. and BAIN, M. 1995. Morphology and micro-habitat use in stream fish. Can. J. Fish. Aquat. Sc. 52 1487 – 1498.

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Appendix 1: Some of the morphological features of fish and their relation to habitat and food dimensions (Adapted from Gatz, 1981).

Category Group Feature Code CommentsHabitat preference and foraging site

Caudal fin

Aspect ratio CFAR High aspect ratio indicates continuous cruising

Caudal peduncle

Flatness ratio CPFI Flat peduncle relates to high amplitude in movementsCaudal span/body depth ratio

CSBD As above the lower ratio relates to a high relative swimming speed

Amount of red muscle RED More muscle in stronger swimmer Relative peduncle length

RPL Longer peduncle in stronger swimmer

Dorsal fin

Dorsal fin position DORP Determines steering abilities

Eye Eye position EYEP Dorsally in benthic species Body Flatness index of body FI Laterally flattened in stiller water and vice versa

Relative body depth RBD Deep body in still water Index of trunk shape ITS High value in cruising species

Lateral line

Lateral line completeness

LLC Incomplete in benthic and sluggish fishes

Lateral line position LLP Indicates benthicity or vertical predator-prey relationshipMouth Mouth orientation MOUO Indicates vertical position of prey

Mouth position MOUP As abovePectoral fin

Area PCA Large in benthic species Aspect ratio PCARDistance from center of gravity

PCCG Anteriorly placed in maneuverable fish.

Length PCL Long fins enhance low speed maneuveringPosition PCP Relates to turning capacity Shape PCS Unclear

Pelvic fin Area PVA Large if fish is demersal Aspect ratio PVAR High aspect ratio for good maneuveringDistance from center of gravity

PVCG Away from centre enhances maneuvering

Length PVL Free swimmers have short fins Position PVP Relates to ability to turn and brake Shape PVS Falcate fins of current dwellers

Features related to food size and type

Number of barbels BARB More barbels in non-optic feeding Number of caeca CAEC More pyloric caeca with more protein in dietEye size EYE Directly proportional to importance of sight in feedingGill raker number GILN The more rakers the smaller the food particlesGill raker shape GILS Long thin rakers indicate small prey Gill raker fine structure GRFS Fine teeth on rakers for large prey. Gut length GUTL Gut length related to diet Jaw tooth presence JAWP Jaw teeth present if large prey is taken Jaw tooth shape JAWS Long pointed or canine like for large preyHypertrophy of teeth PHAR If feeding is through suction Pharyngeal tooth shape PHASMouth protrusibility MOPR Highly protrusible for small prey Mouth height MOUH Directly proportional to prey size Mouth width MOUW Directly proportional to prey size Relative head length RHL Directly proportional to prey size Standard length SL Directly proportional to prey size

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Appendix 2: Illustration of the morphometric measurements and consequent calculations carried out on L. marequensis. Feature Code Measurements between truss marks and calculations.Fork length FL 2 15 Body depth BD 4 5Relative body depth RBD BD/FLBody width BW Caliper measurementRelative body width RBW BW/FLCaudal fin aspect ratio CFAR (7 14) / (7 15)Relative caudal fin aspect ratio RCFAR CFAR / FLCaudal fin area CFA [0,5 (7 15) X (14 15)] + [0,5(7 16) X(7 8)]Relative caudal fin area RCFA CFA/FLCaudal span CS String measurementRelative caudal span RCS CS/FLCaudal span/body depth ratio CSBD CS / BDCaudal peduncle length CL 17 8Relative caudal peduncle length RPL CL / FLCaudal peduncle width RD 7 8Relative caudal peduncle width RCD RD/FLDorsal fin position DORP 3 5Dorsal fin height V 5 9Dorsal fin area DFA 0,5[(5 6) x (6 9)]Relative dorsal fin area RDFA DFA:FLRelative body depth RBD BD / FLPectoral fin area PFA 0,5[(11 13) x (12 13)] Pectoral fin length PFL 11 13Pectoral fin position PFP 18 4 Relative pectoral fin area RPFA PFA/FLPelvic fin length PVL 4 10Pelvic fin area PVA 0,5[(17 19) X (19 20)] Relative pelvic fin area RPVA PVA/FLPelvic fin position PVP 18 4 Eye size (diameter) ED Caliper measurementRelative eye diameter RED ED/FLMouth width MOW Caliper measurementRelative mouth width RMOW MOW/FLRelative head length RHL (2 3) / FL

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ALIEN FISH ERADICATION: PROGRESS WITH THE EIA FOR THE CAPE RIVER REHABILITATION PROJECT.

Dean Impson Scientific Services, CapeNature, Pvt Bag X5014, Stellenbosch 7500. E-mail: [email protected]

Project Objectives

1. Background to the project is given by Stafford and Tweddle in the 2008 Conference Proceedings.

2. Main aim is river rehabilitation – returning otherwise healthy rivers to a more natural condition, by eradicating invasive alien fishes such as smallmouth bass and rainbow trout that threaten biodiversity.

3. Four pilot rivers have been selected. Can we achieve complete eradication in certain areas? – If so, develop protocols for other invaded rivers in priority conservation areas. Experiences in the USA and other first world countries have shown that eradication of alien fishes from river areas above natural (e.g. waterfalls) or man-made barriers (e.g. weir or dam walls) can be achieved in a cost effective way.

4. The project is linked to the development of regulations for alien fish species under NEM:BA. That is because the rivers being targeted for treatment have invasive alien species such as largemouth bass, smallmouth bass and rainbow trout that will be regulated by area (category 2). Outside of designated areas or zones, such alien fishes should be subject to control which can include eradication. Eradication is seen as an important rehabilitation objective in priority aquatic areas. Such areas are presently being identified as part of the National Freshwater Ecosystem Priority Areas project undertaken under the auspices of SANBI.

5. The project is NOT the beginning of a government sponsored campaign to eradicate alien fishes from across RSA or the Western Cape. Point 4 above makes it clear that alien fishes to be regulated by area, such as rainbow trout, carp and largemouth bass, will be protected in designated areas.

6. For the project to be successful it is essential that CapeNature work closely with other authorities (especially DWAF, Dept Agriculture, DEAT, WCape DEA&DP) and key stakeholder groups (riparian land-owners on affected rivers, local angling bodies, environmental NGO’s).

Project progress 1. Progress has been hampered by opposition to the project, primarily by some

trout anglers who have been effective in getting media to write and air hostile articles on the project.

2. Critical articles in media – newspaper reports in the Weekend Argus of 10 May 2009 “Experts slam plans to poison fish”, in The Weekender of 5 July 2008 “Stupidity and venality are not adaptive traits” and on investigative TV programme Carte Blanche in early 2009 that defended the trout industry in RSA.

3. Personal attacks on CapeNature and its employees in Flyfishing Forums, presentations have not aided progress. The focus of these attacks; often incorporating lies, slander and misinformation has been to discredit CapeNature and its staff and thus stop the project.

4. Sadly most of the public opposition has been outside the formal communication channels of the EIA. This is the logical vehicle to engage the project.

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5. Despite this, the EIA consultants have objectively and steadfastly proceeded with their study and have recently released an Environmental Impact Report for public comment

6. The EIR has found in CapeNature’s favour – the rivers proposed for treatment are appropriate, as is the preferred method of treatment (Rotenone). The EIR recommended that physical methods of eradication are tried first in the Krom River, Cederberg, due to the greater sensitivity of this river system.

7. The Cape Piscatorial Society and CapeNature had a successful meeting in February 2009 to discuss matters of mutual concern around the project. Furthermore, both organizations, in late 2008, concluded an agreement that will see priority trout waters in the south-western Cape, including several on CapeNature reserves, secured for trout angling.

8. Five public meetings were held in March 2009 to discuss the findings of the EIR. These meetings were in Cape Town, at Joubertina (Krom River, E Cape) and three in the Cederberg (for the Krom, Rondegat and Suurvlei rivers).

Plans for 2009 / 2010 1. One key issue that arose during conflict around the project was the lack of a

Rotenone policy to guide stillwater and river treatments. CapeNature has recently prepared a draft policy which should be finalized by mid 2009.

2. Complete EIA – likely end April 2009 3. Authority decision hopefully by end May 2009 4. If positive decision – start pre-implementation research and monitoring – mainly

focusing on aquatic invertebrates, as these animals are could be affected by rotenone treatments at the concentrations proposed for treatment.

5. Secure funds for pre-implementation research and actual implementation by mid 2009.

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YELLOWFISH TELEMETRY: UPDATE TO THE EXISTING EWT/WRC/FLYCASTAWAY STUDY AND WAY

FORWARD.

Gordon O’Brien University of Johannesburg, Box 524 Aucklandpark 2006. Email: [email protected]

The yellowfish telemetry study aims to characterise the habitual behaviour of mature yellowfish individuals across changing seasons and environmental conditions. This will be to obtain an indication of the effects of these changing conditions on the biology of these species. This information will be used to establish a yellowfish conservation plan for the Vaal River that has the potential to change the way in which this nationally important aquatic ecosystem is used and conserved. As is to be expected from this type of study, from inception in 2006 more questions seemed to have been raised than answers obtained. We have learned that during some parts of the season individuals may remain in relatively small areas (very small for Smallmouth - +/- 500m and up to 3km for Largemouth) and move continually over large distances during elevated flow conditions. Some individuals seemed to show some signs of territorial behaviour and moved back to precisely the same location as they were captured. Both species appear to have a very good idea of their surrounding areas and during stable climatic periods adopt daily habitual patterns. We are still not convinced that we have determined the time, frequency and location of where Largemouth spawn and we have not determined what environmental conditions are required to act as a cues to initiate the spawning biology of these fishes. To date, this study has involved the continued monitoring of 24 individual yellowfish over two consecutive seasons by Linda Nel (formerly of the University of Johannesburg). In addition to this, we have collected extensive environmental data and are in a position to assess the initial outcomes of the study. These potential outcomes include developing the use of radio telemetry methods to monitor fish behaviour in Southern Africa, the effects of changing environmental conditions on the yellowfishes of the Vaal River ecosystem and it will be a contribution to known biology of these species. Currently the researchers of the study are writing up the outcomes of the initial phase of the study which will be published in 2009. Following the completion of the first phase, the research team feels that we are in a position to build on this information and answer some important questions pertaining to the management and conservation of these yellowfishes. In 2009 the second phase of the study has been initiated. The focus of this phase is to address the breeding biology and general ecology of primarily the Largemouth yellowfish in greater detail. This involves a change in the study area from the Vaal River at Wag ‘n Bietjie Ekoplaas to the Vaal River in the vicinity of Scandinavia Drift (Elgro River Lodge). The second phase of this study has been initiated with the tagging and releasing of a single Smallmouth and a Largemouth yellowfish. Monitoring of these two individuals has been initiated and by the end of June, with the support from local stakeholders, we intend to have the quota of 25 Largemouth yellowfish and 5 Smallmouth yellowfish tagged and being monitored in preparation for the 2009/10 spawning period.

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BUSHVELD SMALLSCALE YELLOWFISH (LABEOBARBUS POLYLEPIS): ASPECTS OF THE ECOLOGY AND POPULATION MANAGEMENT

Gordon O’Brien1, Amanda Austin1, Andrew Husted1, Victor Wepener1, Carel Oosthuizen2 and Paulette Bloomer2.

1 University of Johannesburg, Box 524 Aucklandpark 2006. Email: [email protected] 2 University of Pretoria

This report will be available from the Water Research Commission in 2009. Yellowfishes (Labeobarbus spp.) are of the most easily related to and are amongst the most widely distributed indigenous fishes of South Africa. These fishes are actively targeted and utilised by various angling and subsistence fishing communities throughout South Africa. They are also used as indicator species by resource managers and conservationists to facilitate the management of river ecosystems. This gives them a high ecological, economical and social value to South Africans. Very little is known about these valuable fishes and before we have the chance to fully understand the biology of these species we risk losing them. The Bushveld smallscale yellowfish is a large, small-scaled yellowfish that occurs in the upper reaches of the Limpopo, Inkomati and Phongolo River systems in Southern Africa. Throughout this distribution many fragmented populations of this species occur. Apart from two recent assessments of this species, very little is known and to date no formal conservation initiatives have been established to address the conservation requirements of any potentially unique populations of this species. One population of the Bushveld smallscale yellowfish that historically occurred in the Letaba catchment (Limpopo Province of South Africa) is now locally extinct, potentially due to the unsustainable use of the goods and services of this system by people. This study has been established to address the conservation and/or management implications associated with the potential determination of any unique populations of the Bushveld smallscale yellowfish from five isolated populations of this species from the greater Inkomati and Phongolo River catchments in Mpumalanga. In particular, this study considers potential differences in the biology and ecology of these populations by undertaking selected assessments that are concerned with the genetic and morphological differences between these populations. In addition it considers the occurrence of metals in the liver and muscle tissues within these populations and the feeding biology. This study has been undertaken on behalf of the Water Research Commission by the Centre for Aquatic Research, Zoology Department of the University of Johannesburg in collaboration with the Department of Genetics, School of Biological Sciences, University of Pretoria. The Bushveld smallscale yellowfish populations used in this study were obtained from the Inkomati River catchment including populations from the Elands River, Ngodwana Dam and the Komati River, and two populations from the Phongolo River catchment including populations from the Assegaai River and the Phongolo River. An out-group population of the KwaZulu-Natal yellowfish, obtained from the Umvoti River in KwaZulu-Natal was included in some of the analyses to facilitate the assessments.

69


Findings from the morphological and genetic assessment indicate that consistent morphological and genetic differences do exist between the five populations of Bushveld smallscale yellowfish considered in this study. Based on the genetic assessment of these five populations, findings indicate that three groups, consisting of the Phongolo/Assegaai populations (group 1), individuals from the Komati and selected individuals from the Elands and Ngodwana populations (group 2) and most of the individuals from the Elands and Ngodwana populations (group 3), should be considered as separate conservation units. An extreme case of genetic variation was obtained in this study in the discovery of a group of individuals from the Elands River and Assegaai River that shows a clear unique genetic divergence not only from the remaining populations of Bushveld smallscale yellowfish but also from all of the other small-scaled yellowfishes considered in South Africa to date. Following the morphological assessment, outcomes indicate that although all of the individuals from the populations considered in this study are very similar, consistent differences in the morphology of the populations do exist. Findings suggest that the Elands River and Ngodwana Dam populations of the Bushveld smallscale yellowfish are unique and that they are the only populations that can with certainty be separated morphologically from the other Bushveld smallscale yellowfish populations. Interestingly, this study showed that although the Elands River and Ngodwana Dam individuals of the Bushveld smallscale yellowfish could be separated from the remaining populations considered, no other populations including the KwaZulu-Natal yellowfish, which is a different species, could be separated with confidence in this study. The metal assessment was used as an indication of the extent of metal exposure and uptake in the five different Bushveld smallscale yellowfish populations. The highest concentrations for the selected metals were found in the liver samples for all the sampled populations with the exception of one population which showed the highest Ni concentration in the muscle. However, this was not consistent within all five populations as some populations showed higher bioaccumulation patterns for certain metals in the muscle samples. The metal concentrations found in this study were relatively low and at most, very similar in concentration when compared to other studies completed on other indigenous South African fish species. The results of the feeding biology assessment undertaken in this study suggest that the Bushveld smallscale yellowfish seems to be an opportunistic omnivore that preys predominantly on aquatic macro-invertebrates and also feeds on detritus. This species is well adapted to forage in substrates to capture their prey as well as in the water column and from the water surface. This ability makes this species a successful predator which can adapt to changing ecosystem types and take advantage of various ecosystem niches. This study suggests that different ecosystem types drive the feeding biology of this species of yellowfish and that they may be able to adapt to moderate changes in ecosystem structure and function. This study reveals that not only are there genetically based differences between the populations that warrant conservation action, but that there are also morphological differences that can successfully be used to separate at least two of the populations from the rest of the group. Furthermore this study has revealed that additional experimentation should be undertaken to address the potential genetic differences within this species in order to ascertain if the indication of a unique group of individuals obtained in this study warrants evolutionary significant unit status. This would result in it

70


being established as a new species of smallscaled yellowfish. Of the five populations considered in this study, three groups of populations were determined to be sufficiently different from one another to warrant conservation significant unit status at this time. Very little concerning the other remaining isolated populations of this species throughout South Africa has been considered. Finally, following the outcomes of this study, the current approach to conserve the Bushveld smallscale yellowfish as one species is considered to be erroneous and it is suggested that the isolated populations of the Bushveld smallscale yellowfish that are determined to be unique should be awarded with an individual conservation status and be conserved and/or managed accordingly. Following the outcomes it is recommended that the approach adopted in this study should be expanded to consider the genetics, morphology, biology and general ecology of the remaining populations of Bushveld smallscale yellowfish in South Africa. In addition, the following recommendations should be considered by ecosystem users, conservators, regulators and managers in accordance with the outcomes of this study:

• This study has shown that the isolated population of the Bushveld smallscale yellowfish in the Elands River and associated Ngodwana Dam is unique and as such is of great ecological importance. The conservation status of this isolated population should be addressed with urgency as this population has historically been impacted on by chemical spillages and possibly by genetic contamination through individuals from the Komati River, that have been released into this system.

• More comprehensive geographic sampling of the Bushveld smallscale yellowfish individuals from the systems included in the study as well as nuclear DNA markers, to confirm the past and current gene flow between the separate rivers, is required.

• Further research is required to validate the findings of the metal assessment and to possibly establish causes for the levels obtained in this study.

• Additional assessments of the gut length and/or nutrient uptake potential of the gut of Bushveld smallscale yellowfish should be undertaken to contribute in addressing the uncertainty obtained in this study. In addition, due to the unavailability of seasonal data in this study we recommend that additional feeding biology assessments of this species be carried out during the spring/summer periods. Finally, some stomach morphological assessments should be undertaken which would address the uncertainty of the uptake of detritus matter by this species and similar assessments should be undertaken to address differences within and between the feeding biology of other isolated populations of L. polylepis in South Africa.

71


PROTECTED RIVER ECOSYSTEMS STUDY: BLOUBANKSPRUIT, SKEERPOORT AND MAGALIES RIVERS (GAUTENG)

AND ELANDS RIVER (MPUMALANGA). – CONCEPT DOCUMENT

Hylton Lewis1 and Gordon O’Brien2

1Endangered Wildlife Trust, Private Bag X11 Parkview 2122. Email: [email protected]. 2 University of Johannesburg

The Endangered Wildlife Trust has commissioned a study to establish a comprehensive proposal to assess aspects pertaining to the rationale, development and management of river protected areas in South Africa. Introduction: Ecosystem diversity is the key to efficient ecosystem functioning. It is this biodiversity on which many industries from pharmaceutical to tourism are based and many of the services that natural biodiversity offers are vital to both human and animal life. In essence healthy functioning ecosystems are the life support systems on which we rely and their continued abuse is unsustainable. The establishment of protected areas is a principal means for conserving South Africa’s biodiversity. Today more than 1200 national parks, wildlife reserves and other categories of protected areas representing more than 2 million square kilometres exist. Although there is a commitment to biodiversity conservation throughout Africa, the capacity and resources required to carry out these endeavours effectively are not available. This results in enormous pressure being placed on the supposedly protected ecosystems by growing populations, excessive exploitation of natural resources and unsustainable development that ultimately leads to the degradation of the natural habitats. Activities that threaten biodiversity such as over-exploitation of individual species, poor relations with relevant stakeholders, lack of funding and alien invasive species are real and severe. Furthermore, agencies directly mandated to undertake conservation efforts often lack the capacity to implement comprehensive management strategies. There is often a lack of dialogue with the diverse stakeholders, an indispensable factor in the conservation practice. The involvement of local communities in the planning, establishment and management of protected areas can provide human resources and due to their vested interest, on-site management of ecosystem use. While the standard practice of conservation is not new, primary conservation efforts are often centred on terrestrial ecosystems. While this may be suitable for terrestrial ecosystems they do not always afford protection for the aquatic ecosystems that pass through these terrestrial “islands”. To illustrate this, within South Africa large national parks contain river ecosystems that are currently in a poor ecological state and are not provided with adequate protection as the protected areas do not encompass the source of the rivers that pass through them. Despite the level of protection afforded within current protected areas, impacts occurring outside can still have consequences for the freshwater biodiversity within. There is an urgent need for protected areas that specifically target freshwater habitats and protect biodiversity, representative habitats, threatened species and intact habitat remnants. It is important that these protected areas guard against primary threats to freshwater ecosystems. Research into protected area design focuses on general

72


conservation principles, but such is the nature of rivers that it may be necessary to approach the demarcation of protection in a new manner and to consider the overall management to ensure complete catchment integrity. Currently there are no standard protocols on which to base the design and management of river protected areas, however, local efforts that do show promise are evident. The Elands River Yellowfish Conservation Area (ERYCA) is a conservation initiative which has been established to conserve a 60km segment of the Elands River (Mpumalanga) which is isolated by two waterfalls. The ERYCA aims to promote the sustainable use of a unique population of Bushveld smallscale yellowfish (Labeobarbus polylepis) as a flagship species, thereby facilitating the conservation of the biodiversity of this aquatic ecosystem. It also aims to develop the yellowfish in this river as a valuable sustainable resource for the local communities. Although this endeavour does recognise the need for the development and/or use of a range of goods and services offered by the Elands River (such as yellowfish angling) to support the conservation efforts, the conservation of this system should not be dependent on these resources. As such a tight line between the use and conservation of the goods and services of the Elands River is being established. This aquatic ecosystem was considered by public and private, local and national use, conservation and management stakeholders to be of immense value. This was due to the current relatively pristine ecological state of the system which currently maintains a vast diversity of aquatic organisms, some of which are listed as being rare, endangered and in the case of the Inkomati Rock-catlet, critically endangered according to the International Union for the Conservation of Nature (IUCN). It was proposed in 2002 that this segment of the Elands River be declared a conservation area and the result was the formation of the ERYCA strategy in 2004. The ERYCA was developed in 2004 and in 2009 (five years later) the conservation initiative exists in principle but has not become operational. Some reasons which have been ascribed, by stakeholders, to the delayed implementation include limited ecosystem resources, in the form of yellowfish that can be used to generate resources for the initiative. Other reasons include limited external financial and skilled human resources for the endeavour, and the inability of the ERYCA members to establish an awareness programme and again for them to maintain day to day operational activity expenses. This study aims to address these shortcomings. Additional river systems that have been identified as potential case studies for protected area establishment are the Bloubankspruit, Skeerpoort and Magalies rivers (Gauteng). These aquatic ecosystems are considered to be in a relatively good ecological state when compared to other Gauteng rivers. Through the actions of local land owners, registered water users, aquatic biologists and public organisations they can be afforded some protection in terms of provincial biodiversity conservation endeavours. The Bloubankspruit is a small perennial tributary of the upper Crocodile River, upstream of the Hartebeespoort Dam, west of Johannesburg. This small tributary originates in the Kromdraai area of western Gauteng, specifically in the Swartkops area/Sterkfontien caves. It then flows north-easterly and enters the Crocodile River at the confluence located on the Glenburn Lodge estate. Within the catchment of the Bloubankspruit various anthropogenic activities, including agricultural, small industrial, waste water treatment works, limited mining activities and recreational activities occur. In the Bloubankspruit a wide variety of indigenous fishes still occur, in fact, as of 2006, the

73


diversity of fishes in the Bloubankspruit is considered to be somewhat comparable to natural conditions. In Gauteng where a vast majority of the local fish communities have been severely impacted by altered water qualities, habitat destruction, flow alterations, excessive water abstraction, population fragmentation, excessive harvesting and many other stressors, few areas remain in a state similar to that of the Bloubankspruit. An additional two river ecosystems in the upper Crocodile River catchment (Gauteng) that do warrant conservation action, due to the high ecological importance of the systems based on the aquatic biodiversity of the systems, includes the Skeerpoort and Magalies rivers. Of the possible 21 fish species which may occur within these systems at least two species are listed red data species whilst an additional seven species can be considered to be listed as having local and or provincial endangered status. The protected rivers conservation endeavour may potentially provide a sanctuary for these endangered species along with an additional local endemic species standing to benefit from the endeavour. It is recognised that conservation efforts centred on a single species are not always effective. A species becoming threatened may indicate an already degraded ecosystem, it is reasonable to believe that this programme will be able to afford protection to the various ecosystems due to their current relatively pristine state. It is the aim of this study to establish a complete proposal pertaining to the development and management of protected rivers. As part of this it will be our aim to promote the areas of the Bloubankspruit and the Skeerpoort and Magalies rivers (Gauteng) in the greater Magaliesberg in the same manner as that proposed for the Elands River (Mpumalanga) and these will serve as case studies for future reference. It will be required that the following tasks be carried out in order to achieve these aims.

1. Carry out a desktop assessment considering the motivation for, and an approach needed to have a protected river ecosystem established along a segment of relevant rivers.

2. Collect information pertaining to the establishment of the Elands River Yellowfish Conservation Area in Mpumalanga for use in the proposal.

3. Carry out a reconnaissance and low confidence survey of the Bloubankspruit and Skeerpoort River to collect initial information for the establishment of the proposal.

4. Establishment of a comprehensive proposal titled: Protected river ecosystems study using the Bloubankspruit, Skeerpoort and or Magalies River (Gauteng) and Elands River (Mpumalanga) as case studies.

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LEGISLATIVE REVIEW: A CRITICAL REVIEW OF THE LEGISLATIVE FRAMEWORK FOR ANGLING IN SOUTH AFRICA

Morné Viljoen CLS Consulting Services (Pty) Ltd. Email: [email protected]

Angling in South Africa is governed by a plethora of contradicting laws. Anglers are faced with national legislation, as well as contradicting legislation pertaining to the same fish species in different provinces. The following legislation is directly applicable to anglers in the various provinces: Province Applicable LegislationEastern Cape • Cape of Good Hope Nature & Environmental Conservation

Ordinance (Cape Ordinance), • Threatened or Protected Species Regulations (TOPS Regs) • Alien and Invasive Species Regulations (AIS Regs) (possibly to

be enacted in 2009) and • Marine Living Resources Act (MLRA)

Western Cape • Cape Ordinance, • TOPS Regs and • MLRA • AIS Regs

Northern Cape • Cape Ordinance, • TOPS Regs and • MLRA • AIS Regs

North West • Cape Ordinance; • Transvaal Nature Conservation Ordinance, and • TOPS Regs • AIS Regs

KwaZulu-Natal • Natal Nature Conservation Ordinance, • TOPS Regs • AIS Regs • MLRA

Mpumalanga • Mpumalanga Nature Conservation Act • TOPS Regs • AIS Regs

Free State • Free State Nature Conservation Ordinance and • TOPS Regs

Gauteng • Transvaal Nature Conservation Ordinance • TOPS Regs • AIS Regs

Limpopo • Limpopo Environmental Management Act • TOPS Regs • AIS Regs

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Each province views angling and angling permits, conservation and management of its freshwater resources differently. With the introduction of the TOPS Regs (and the Alien Invasive Regulations to be introduced shortly), we now also have national legislation governing fish that’s already been governed by provincial legislation. The abovementioned legislation is to be implemented by the National Department of Environmental Affairs and Tourism (DEAT), as well as the provincial departments managing environmental matters. Add to the mix the National Water Act in terms of which the Department of Water Affairs and Forestry (DWAF) must protect the “biological characteristics of water” as well as the “characteristics, condition and distribution of aquatic biota” and we have a recipe which leads to confusion amongst anglers and government officials alike. In the process legal certainty, a corner stone of a sound legal system is lost. In light of the above, I conducted a study to ascertain how anglers feel about the situation. The questionnaire was published in the Tight Lines Magazine and other anglers were contacted via e-mail. The results are as follows:

Do you think we should have angling licences in SA at all?

89

11

0

20

40

60

80

100

Yes No

%

76


What should the licence fees be used for?

44

37

31 30 30

2421

42 1

05

101520253035404550

Number of respondents

Conservation of f ishhabitat Conservation of f ishstocksCombating Water Pollution

Upkeep of angling w aters

General EnvironmentalConservationAdmin. and enforcement ofangling legislationAll of these

Community upliftment &aw arenessFunding of angling bodiesand clubsOther

How much are you willing to pay for a national angling licence (per year)?

9%

26%

27%

28%

10%

0

50

100

150

>150

77


Is there a need for a single national angling licence?

Yes

No

Yes

No

Should there be a single, national law for angling?

Yes93%

No7%

78


Should there be separate licences for fresh and salt water angling?

Yes55%

No45%

Should there be separate legislation for each province, each with its own licence?

Yes7%

No93%

79


Should there be separate legislation for each province which is summarised on a single

national angling licence?Yes28%

No72%

Should there be separate legislation and licences for each province?

Yes5%

No95%

80


Where should one be able to obtain an angling licence?

6456

38

17 14 10

010203040506070

Num

ber o

f res

pond

ents

How many rods should an angler be allowed to fish with?

2

46

1321

0 0

17

0

10

20

30

40

50

1 2 3 4 5 6 No limit

%

81


How many hooks per rod should an angler be allowed to fish with?

10

69

714

0

20

40

60

80

1 2 3 No limit

%

Should anglers be prohibited from using keep nets?

Yes11%

No89%

82


Should all species of fish caught be released?

Yes18%

No58%

Only indigenous

species24%

Should feeding places be allowed?

Yes49%

No51%

83


Should markers for feeding spots be allowed?

Yes35%

No65%

Should fresh water anglers be allowed to fish with live bait?

Yes77%

No23%

84


Should anglers be forced not to return any alien invasive species?

0102030405060

Yes No Only in certain zones

%

Should fishing with gill nets/any other manner of fishing that does not involve a rod and reel

be allowed?Yes17%

No83%

85


Should anglers in possession of an angling licence be allowed to enter any angling

waters, without having to pay and entrance fee?

Yes17%

No45%

Only in respect of

government property

38%

In an interview with the Department of Environmental Affairs and Forestry (DEAT) it was indicated that, the TOPS Regulations will be applied in such a way by the government departments that a TOPS permit will not be required where one practices catch and release. DEAT is also contemplating looking at drafting a single, national licensing system for freshwater angling, although this is a mere thought at this time and no work has been done in this regard. However, DEAT is apparently not keen on separate legislation just for angling. A possible solution will be to list all fishes in South Africa either as “Threatened or Protected” or as “Alien and Invasive”. A single, national licence is then issued, dealing with each species, making provision for provincial circumstances (i.e. where some species are to be protected in one province, but is to be regarded as invasive in another. An electronic licensing system for freshwater angling may also be looked at in future.

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SMALLMOUTH YELLOWFISH, LABEOBARBUS AENUS, STATUS IN THE GREAT KEI CATCHMENT

U. Tshayingca1, S.Mzileni, E. Weni. Department of Water Affairs & Forestry, Box 7019, East London 5200. 1Email:

[email protected]

ABSTRACT Resource Protection, within DWAF, conducts seasonal biomonitoring in both WMA 12 and WMA 15 rivers, within the Eastern Cape. Indices used in determining river condition are drivers such as water quality, geomorphology and riparian vegetation; which affect the responders such as invertebrates and the fish. L. aenus has been introduced in the following systems to mention but a few, the Great Fish, Kei and Mbashe and has now infested these systems, together with their tributaries. Its natural range is the Vaal-Orange system (Skelton) Great Kei sampling proved that this fish prefers fast deep water, where there is bedrock, boulders and cobbles. Habitat degradation (resulting from sedimentation) is a threat to this fish community. Juveniles were always caught in slow deep water. This is usually the “pocket” or backwater of the main stem. Skelton recorded that this fish preys on small fish, including, but not limited to, the indigenous chubby headed barbs, Barbus anoplus. This has been evidenced by the diminishing numbers of the B. anoplus in these systems. In areas where the river forms a secondary channel (usually slow shallow), the indigenous barbs use that channel as a refuge to escape predation by the adult yellowfish. The juvenile yellowfish co-exist with the indigenous minows in the backwater or secondary channel. Smallmouth yellowfish have easily adapted to this system as they were abundant throughout the catchment and showed no signs of infection.

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STATUS OF YELLOWFISH POPULATIONS IN KWAZULU-NATAL

Rob Karssing Senior Aquatic Research Technician, Biodiversity Division, Ezemvelo KZN Wildlife, P.O.Box 13053,

Cascades, 3202. E.mail: [email protected] Species present There are three indigenous yellowfish species in Kwa-Zulu Natal, including the ubiquitous KwaZulu-Natal Yellowfish Labeobarbus natalensis which is widespread from the Mkuze River southwards to the Umtamvuna River on the Eastern Cape Border. This fish occurs at altitudes as low as 100 m and may migrate into the Drakensberg to altitudes of 1500 m or more during the summer months. The other two species include the Bushveld Smallscale Yellowfish Labeobarbus polylepis and the Lowveld Largescale Yellowfish Labeobarbus marequensis, both of which are restricted to the Phongolo system in northern KZN. Although there may be some overlap between these two species, L.polylepis is a more temperate species typically inhabiting rivers above 600 m while L. marequensis on the other hand prefers warmer water and is generally limited to altitudes below 600 m. Status of species Although widely spread throughout the province the KwaZulu-Natal’s yellowfish are coming under increased pressure due to man induced habitat change. Freshwater fish are globally the most threatened group of vertebrates after amphibians with more than a third of all species currently threatened with extinction. Threats Pollution has come to the forefront as being one of the major threats to yellowfish in KZN. A major pollution event occurred in the Mgeni River at Howick towards the end of last year when yellowfish, barbel, bass and carp were killed by pollutants. The main source of pollution emanated from the Siphumele Township and Thokoza informal settlement on the outskirts of Howick. Despite numerous earlier complaints to the Umgeni Municipality about the state of overflowing sewers and dysfunctional sewage pumping stations, no direct action was taken by the authorities until reports were received about fish dying downstream of the point source of pollution. Besides yellowfish, hardy species like bass, barbel and carp also died in this incident. A report was also received about a dead Cape Clawless Otter. An investigation by DWAF officials revealed that the small stream which leads through the Siphumele/Thokoza settlement, had astronomical high e-coli and unionized anmmonia levels that were largely instrumental in creating the fish kill. The investigation also revealed the presence of milk solids in the stream which originated from the Fairfield Dairy processing plant. The pollution event occurred at a time when the flow in the river, although regulated by a release of water from Midmar, was low and water temperatures were increasing. It is surmised that a progressive build of pollutants, low oxygen levels, and unnaturally high levels of un-ionised ammonia, produced a lethal concoction of toxins resulting in the massive fish kill. Several local authorities can be held responsible for this incident; the local uMngeni municipality that was ironically in the process at the time of transferring the responsibility for sewage treatment to the greater Umgungundlovu district municipality, Umgeni Water Board, and ultimately DWAF. Ezemvelo KZN Wildlife have proposed at a recent Upper Mngeni Catchment Management Agency (CMA) that

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water released from Midmar en-route to Albert Falls, be periodically pulsed during early spring period as a proactive measure to flush out toxins which could accumulate in the system. A regulated flow of approximately 0.5 cumecs is routinely released from Midmar Dam. The Howick West sewage plant remains a concern since it flushes treated water down a hillside directly into the Umgeni Valley Nature Reserve managed by the Wildlife and Environmental Society of South Africa (WESSA). Water released from this facility is in many instances sub-standard and according to an Umgeni Board can be related to ongoing technical problems as well as the presence of specific bacterium in the system that prevents the flocculation and sedimentation of solid matter. The compliance rating of this facility is currently set at 76%. 21 % of residents of Howick’s residents currently do not have adequate sanitation while 43 % do not have refuse removal. A further 3 457 households have been added to the sewage reticulation system at Howick without further enhancements to the existing infrastructure. Another matter of great concern is the proposed increase in the HEP generating capacity of the Drakensberg Pumped Storage Scheme. With the advent of Katze Dam as an additional source of water for the Vaal the focus of the Thukela-Vaal inter-Basin Transfer Sceme (IBWTS) has shifted more towards it power generation capabilities. To the best of our knowledge water released into Kilburn Dam (KZN) from Sterkfontein Dam (OFS) for HEP purposes has to date never overflowed directly into the Thukela system. It is a well known fact that Kilburn Dam has a full complement of Orange-Vaal species as well as a host of exotic species that could potentially invade the Thukela system. There have been a few records of some escapees which can be linked to DWAF operation staff testing release valves without having adequate screening in place. Eskom is seeking permission to allow the dam to overflow should they be faced with a “black start”. A “black start” relates to a major blackout occurring in the national grid whereby Eskom would seek to use an alternative supply source (not coal fired) that can fed into the national grid at short notice. A similar HEP installation is being developed at Braamhoek where “surplus” power generated by coal fired power station at night will be used to pump up water during the night (low demand period) and released via turbines during the day (low demand period). In essence, the stored water in the high altitude dams effectively function as large batteries, releasing their stored energy as water is released back via giant turbines to receiving dams on the KZN side of the water. Ezemvelo KZN Wildlife formally objected to a proposal by Eskom to release the overflow water of Kilburn Dam directly into the Thukela River. Africon environmental consultants were commissioned by Eskom to obtain environmental authorization from DEAT for the proposed increase in HEP generation. Subsequent discussions with the department revealed that an EIA was not required in terms of national legislation for the activity. They did indicate however that it would be good policy for Eskom to undertake a risk assessment which could help make informed decisions on this issue. It was further proposed that Eskom undertake some form of public participation as well as incorporate their recommendations into a Biodiversity Management Plan (BMP). The fish study was to be conducted by Johann Rall of Golder and the BMP completed by Africon consultants.

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Another matter of great concern is the increase of poaching taking place primarily in the vicinity of state controlled dams. In most instances Yellowfish are becoming decimated at several localities during their annual spawning runs. Some of the worst poaching is taking place at Inanda and Nagle Dams. Poachers are using high quality gill nets and are also attempting to buy cast nets at local tackle shops. The management authority of Inanda (Msinsi) is unable to cope with the magnitude of the problem and has requested the involvement of EKZNW. It would appear that in most instances that the poaching is taking place on an organized basis with the bulk of the catch being marketed in the Durban metropolitan area. Although EKZNW is the mandated authority to deal with fish poaching problems it also lacks the capacity to do so effectively. A task team comprising of concerned anglers and police reservists carried out a surprise raid on both Inanda and Nagle Dams. The team recovered more than 500 m of gill nets, destroyed two boats and confiscated six other in three days of raiding. There were some reported incidents of the task team being fired upon by local community members as they removed gill nets. This raid was privately funded with the cost of fuel alone amounting to R 3000. A new threat in KZN is the occurrence of armoured sail-fin catfish Plecostomus spp in the Mhlatuze River and tributaries in the Richards Bay/Empangeni region. It is uncertain whether these alien fish, which have been introduced into the natural environment via the aquarium trade, will overlap with the distribution of yellowfish. It is predicted however that these South American aliens are going to flourish in the sub tropical climate of KZN wherever they unfortunately occur. Conservation measures to conserve the yellowfish resource (1) Establishment of conservancies and conservation areas Ezemvelo KZN Wildlife’s stewardship programme supports yellowfish conservation

The new EKZNW stewardship programme recognizes that a large proportion of the rich biological diversity of KZN is not being adequately protected, but is instead found on privately and communally-owned land. This new initiative encourages landowners within the province to become partners with Ezemvelo KZN Wildlife in applying the stewardship principles on their land and to take responsibility for the protection of these particular assets. The programme offers various stewardship options to landowners who retain all ownership rights and can tailor-make an option to suit their particular situation and needs. Nature reserve status was conferred on the Dalton Private Reserve which is located just upstream from EKZNW’s Moor Park Nature Reserve on the Bushmans River. This section of the Bushman River is home to formidable annual run of KZN Yellowfish which makes their way up from Wagendrift Dam and venture as far as the Giants Castle Game Reserve. The management staff of Dalton Private Reserve has successfully cleared the river banks on their property of invasive wattle trees and other alien vegetation. A similar stewardship agreement was signed with the Mbandala Traditional Authority along the Ngwangwane River which supports both exotic trout and yellowfish. The signing of these agreements allows landowners to formally become part of the conservation network in the province, and in this way it is hoped that unprotected biological assets will receive the protection they need, while giving landowners an added sense of pride in their biodiversity conservation contribution.

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(2) Stocking Ezemvelo KZN Wildlife does not support the movement of yellowfish outside of their natural range for recreational fishing. (3) Education and awareness (4) Legislation The introduction of a national freshwater fishing licence would assist greatly in making the yellowfish resource more sustainable. There would need to be general agreement however amongst all the provincial nature conservation authorities to achieve this goal which may take several years to implement. Funds from the collection of licences could be used for both compliance and research purposes. In the short term however it would wise to extend the protection of existing legislation to cover certain other yellowfish species by also including them among the list of protected species listed in terms of the current TOPS regulation. I believe that a strong case could be made for the added protection of the KwaZulu-Natal Yellowfish L.natatalensis since it is an endemic species of the province that is long lived and which grows slowly. The fish also has a high recreational value as a freshwater sport fish. Currently populations of this species, although generally common in the province, are largely becoming decimated by unscrupulous poaching. Much of this poaching is taking place during the annual spawning run when large numbers of these fish congregate in shallow water at the head of streams and at the base of barriers like waterfalls and dams, this makes them highly susceptible to poaching. Having a protected status would require that all anglers have a TOPS permit to capture them. Conditions of the permit can potentially stipulate both a bag and a size limit for the species. Hefty fines, in terms of a contravening the regulations of a national act, could then be imposed by the courts on persons abusing this valuable natural resource. (5) Monitoring No dedicated monitoring programmes have been implemented by Ezemvelo KZN Wildlife towards the monitoring of yellowfish in the province. The occurrence of yellowfish in field surveys is treated more incidentally as part of the fish assemblages. EKZNW is currently more committed to carrying out field surveys that provide representative samples of the fish assemblages occurring in aquatic bioregions identified by its systematic conservation plan. (6) Research Research has been carried out by Prof. Paulette Bloomer on the genetics of KZN Yellowfish (Labeobarbus natalensis). Her results indicate distinct genetic differences between geographically isolated populations in this province. Many of KZN’s river systems flow eastwards and are isolated from one another spatially. (7) Value of yellowfish resource to anglers and subsistence fishers KZN Yellowfish are increasingly becoming a more valuable natural asset to the province as the free supply of products and services provided from the natural environment become eroded away by man induced habitat change.

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FREE STATE STATUS REPORT

Johan Hardy Manager, North & East region, Free State Nature Conservation, P O Box 1965, Welkom 9460. Email:

[email protected]

The Free State Department of Tourism, Environmental and Economic Affairs do not have a fish scientist at the moment. Johan Hardy from the Sub Directorate Environmental Empowerment and Awareness is doing it as part of his job description through Forums. The Orange Vaal River Yellowfish Conservation and Management Association’s management team has been registered as the Vaal River Yellowfish Forum. Does the Free State have a water crisis, not possible? According to the map, we are right in the middle and thus have Sterkfontein in the East; Vaaldam in the north, Bloemhofdam in the west and Gariep in the South, so see, there is more than enough water. Some of these dams are connected by canals, either to import of export water. So see, if we are short, we call and they send water by pump. Either imported or connected by canal to export, what a pleasure to use it for recreation, or fishing to be exact. But can we have an invasion, an invasion of what? Dark clouds are hanging over our precious water because lots of stuff can go wrong, but like what? Are the Free State’s freshwater fish one day going to be only aliens or genetic modified due to the doings of Homo sapiens. We are importing and exporting water from other water catchments in other provinces, what if fish, eggs, larvae etc are being transported through this intervention. Proof exists that the Small and Largemouth Yellowfish and Oranje River Mud fish went through to Killburn dam, from Sterkfontein. Then it must be vise versa that fish endemic or alien to KZN might be a possibility in Sterkfontein. The Natal Scaly and Smallmouth are from the same genus and can interbreed, this must be checked out. If it is so and water is transferred from Sterkfontein into the Vaaldam system, what then? Is it really then neccesary to try and not move fish from one system to another if it might be already infested? A proper fish survey has to be done to determine the status of fish populations in each water catchment. If they are connected, they must be managed like that. Only the separate geographic rivers must then be managed as an entity, with no movement of fish between them. AS in the case of KZN, they have 5 different catchments, each with his own gene pool. Let us look at the water we receive from the Vaal, Klip, Riet and Barrage. By sight it seems clean and nice water to use for recreational purposes, but! A Transdiciplinary study on the water quality of the Vaal River from Barrage down to Schoemansdrift was undertaken by Potchefstroom University, under leadership of Prof. Johann Tempelhof. The team exist of different persons from Water Affairs, Potchefstroom University, Landowners, Business people, Municipal officials, Health officers, Environmentalists, Human resources etc.

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Water samples were taken to test for Cryptosporidium, Garnea and other unsafe coli forms that could exist in the river. Physical site inspections took place and here the local community which were found near or next to the river, were interviewed to find out how they are experiencing the river. People directed or showed us problems which they knew of in the river. Signs of pollution were visible, “stuff” drifted on the water; some dead fish were floating past. Toilet outlet pipes ran into the river, lots and lots of hyacinths and other plants usually found in sewer plants, were sighted on the river and along the banks. Culprits of serious pollution in the study area were private riparian land owners and local municipalities. A person pumped water from the river to irrigate his resort and fill up the small dam for animals, the pump was leaking lots of oil and it on the bank of the river. A Chinese toilet paper factory was sending their effluent, white paper pulp and chemicals, through a marshland down to the river. The Parys sewer works did not operate and spillages occur on site; it flushed down to the river. The final effluent showed lots of solids still within, whilst it was released into the river. The Parys Aquatic Weeds Forum is managed by Working for Water, DWAF. Quarterly meetings are held in Parys where feedback is given to the community and issues related is discussed. Contract teams do mechanical clearing and chemical spraying are being done by rubber duck on the water. Problem is that some of the teams have been found taking river water to dilute the herbicide; this is useless due to the herbicide to disintegrate because it was formulated to do so, to be aquatic invertebrate and fish safe. However biological control agents exist, they are more than once spayed and then die. The sprayed plants die and sank to the bottom where they rot, and the breaking up process releases ammonia which is toxic to fish and other water life. The Orange Vaal River Yellowfish Conservation and Management Association were established to enhance the survival of mainly the Largemouth Yellowfish, however all other indigenous species are benefiting from this effort. We promote Yellow fish conservation through awareness initiatives, like stickers, posters, billboards and making use of volunteers. Fishermen are encouraged to report fish mortalities, diseases, big catches etc. The catch and release program ensured that fish up to 13 kg were caught recently, were it was difficult to catch a fish bigger than 3 kg several years ago. Threats to our water systems are chemical and fertilizer over use which leads to seepage and spillages which land directly in our water systems, causes fish deaths. Blocked sewer manholes and pipelines are the order of the day, millions of litres of raw sewage ends up in our water systems daily. What is the effect of hormones, excretion of body diseases which ends up in our water systems; surely it must have an enormous effect? Yes you can do something, before pointing a finger, know that 3 are pointing back to you, asking you, are you right in what you do. Thus start now and practice what you preach. Awareness is our only weapon to fight this threat facing us, act now. Thanks for the opportunity and know that all is fine for 2010, and enjoy fishing in our clean water.

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YELLOWFISH REGIONAL REPORT FOR THE WESTERN CAPE 2008/2009

Martine Jordaan1 and Dean Impson2 River Conservation Unit, Scientific Services Division, CapeNature Pvt Bag X5014, Stellenbosch 7500.

Email: [email protected]; [email protected]

Summary

The Western Cape Province has four yellowfish species, three of which are indigenous (Skelton, 2001). These are the Clanwilliam Yellowfish (Labeobarbus capensis), the sawfin (Barbus serra) and the whitefish (Barbus andrewi). The latter two species are considered endangered, while the Clanwilliam yellowfish is considered as vulnerable according to IUCN criteria (Impson, 2007). The smallmouth yellowfish (Labeobarbus anaeus) naturally occurs in the Orange-Vaal system, but has been introduced to the Gouritz river system in the Western Cape where it is considered an alien invasive species. The main threat to indigenous fish species, including the yellowfishes, in the Western Cape is the widespread occurrence of alien invasive species such as bass (Micropterus spp.), rainbow trout (Onchorynchus mykiss), bluegill (Lepomis macrochirus), carp (Cyprinus carpio) and catfish (Clarias gariepinus). These species negatively impact indigenous fish through predation, competition and habitat modification. Studies by Shelton (2003), Woodford et al. (2004) and Lowe (2008) have clearly illustrated the negative effects that the presence of alien fish has on indigenous fish and general river ecology. Other threats to indigenous fish include invasive alien plants, water over-abstraction, agrichemical pollution and uncontrolled habitat degradation, especially within commercial deciduous fruit farming areas. Taking into account the current conservation status of yellowfishes in the Province, there is an urgent need for a partnership between the private sector (WCYWG) and the formal conservation sector (CapeNature) and an important development for 2009 is the proposed close cooperation between the two parties. The WCYWG has a critical role to play in yellowfish conservation in the Western Cape and their priorities for 2009 have been formalized and communicated to CapeNature towards the end of 2008. These have been evaluated and approved by CapeNature by early 2009 and the way forward will be the implementation of proposed WCYWG actions with assistance of CapeNature. The aims of WCYWG include:

1. To protect healthy populations of yellowfishes presently found in the Western Cape Province.

2. To restore depleted populations in sections of the Doring-, Olifants-, Berg- and Breede River systems.

3. To maintain and improve habitat and riparian zones in river systems where yellowfish are found.

4. To stimulate research and improve awareness of the species. CapeNature, with the assistance of the Department of Water Affairs and Forestry (DWAF) is presently implementing the national River Health Program (RHP) in the Western Cape through the River Conservation Unit (RCU). The RCU consists of aquatic scientists from both CapeNature and DWAF’s Resource Protection Unit, and staff members are in the process of finishing a comprehensive assessment of the greater

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Breede River using a number of biological indices. The main findings of the assessment include:

• The 1/100 year flood that was experienced in the second half of 2008 resulted in large scale environmental damage to most of the Breede catchment. This was followed by extensive bulldozing in many parts of the catchment, especially around the town of Montagu and in the Hex River valley.

• After surveying almost 50 sites throughout the Breede river system, no whitefish were caught at any of sites surveyed. This is a shocking finding for a species that was widespread and abundant throughout this system until alien fish started to dominate the system after the 1950s. Since the 1/100 year flood event and the resultant bulldozing activity, there is also no record of whitefish population that occurred in the Hex River. On a positive note, a small population of whitefish was found immediately below the Roode-Elsberg dam on the Sanddrif River in the Hex River Valley. The local farmers report that the dam itself has a large whitefish population but CapeNature has not yet verified this.

• The spread of Sharptooth catfish in the Breede River system is a major source of concern. This species was not recorded in the system prior to 1990 and their presence in the Breede system is the result of illegal introductions. Sharptooth catfish have now widely invaded the system, including several tributaries such as the upper Keisie River outside Montagu and the Hex River near De Doorns. The latter area is a priority area for indigenous fish conservation and is presently home to large populations of galaxias (Galaxias zebratus), Cape Kurper (Sandelia capensis) and redfins (Pseudobarbus burchelli). The presence of catfish will no doubt have a deleterious impact on the indigenous fish assemblage of the Hex River.

The way forward for the year ahead:

The WCYWC has identified the key issues for yellowfish conservation in the Western Cape and a Yellowfish Management Plan is now needed. The WCYWG, with the assistance of CapeNature, will aim to identify and work closely with farmers and landowners who have an interest in yellowfishes so that these fish can be stocked into suitable farm dams and stretches of river where the introduced fish will have a good chance of surviving and becoming established. It must be noted that the stocking of these fish will be subjected to strict genetic principles to prevent genetic contamination of distinct populations. Stocking will also only be allowed within the historic distribution range of a species. The work of the RCU continues and after completion of the comprehensive survey on the Breede River the surveying of the Berg River system will start. Another positive development is the aquatic stewardship program that is envisaged for the greater Cederberg area. This project will focus on the identification of areas that are of importance for conservation of priority aquatic ecosystems. This will include several rivers with Clanwilliam Yellowfish (Labeobarbus capensis) and sawfin (Barbus serra). The proposed Ratels River Yellowfish Conservancy in the Porterville area is presently on hold and a final decision will be made once an invertebrate assessment is complete. Regarding the proposed CAPE Alien Fish Eradication Project, CapeNature is pleased to report that the EIA team has found that the rivers selected as pilot projects to be appropriate, as is the preferred method of eradication (rotenone). The Environmental Impact Report is presently out for public comment and the project is discussed in greater detail in these proceedings in the project summary of Impson (2009).

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References

IMPSON, ND (2007) Freshwater Fish Chapter, Western Cape Province State of Biodiversity Report: 19-34.

LOWE S, WOORDFORD DJ, IMPSON ND, DAY JA (2008) The impacts of invasive

alien fish and invasive alien plants on the invertebrate fauna of the Rondegat River, Cape Floristic Region, South Africa. African Journal of Aquatic Sciences 33(1): 51-62.

SHELTON JM, DAY JA, GRIFFITHS CL (2003) Influence of largemouth bass,

Micropterus salmoides, on abundance and habitat selection of Cape galaxias, Galaxias zebratus, in a mountain stream in the Cape Floristic Region, South Africa. African Journal of Aquatic Sciences 33(3): 201-210.

SKELTON P (2001) A Complete Guide to the Freshwater Fishes of Southern Africa.

Struik Publishers, Cape Town, South Africa, 395pp. WOORDFORD DJ, IMPSON ND (2004) A preliminary assessment of the impacts of

alien rainbow trout (Onchorynchus mykiss) on the indigenous fishes of the upper Berg River, Western Cape, South Africa. African Journal of Aquatic Sciences 29(1): 107-111.

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RIVER MONITORING IN LIMPOPO PROVINCE 2009

MK Angliss1 and SSM Rodgers Limpopo Environmental Affairs. Box 217, Polokwane 0700. 1Email: [email protected]

Abstract. The Biodiversity Section of Limpopo Environmental Affairs continues to progress with limited staff. During 2008, the section undertook a systematic survey of the Matlabas River Catchment. Due to the presence of Marakele National Park, the survey was conducted in collaboration with South African National Parks (SANParks). Technical reports on the survey were written (Angliss et al 2008) while additional poster publications have been produced to publicise findings of earlier surveys. The Biodiversity Section undertakes such river surveys, primarily to collect State of Environment Report (SoER) monitoring data, while coincidentally championing work under the auspices of the River Health Programme (RHP). The future of the RHP in Limpopo Province as a stand alone programme is seriously questioned due to the poor performance of the Department of Water Affairs and Forestry (DWAF) in implementing environmentally friendly actions. 1. River Monitoring. 1.1 The Matlabas River Catchment. The following text is extracted from the executive summary of the Matlabas report as prepared for Limpopo Dept. of Economic Development Environment and Tourism (LEDET) by Angliss (2008)

The Matlabas River Catchment was surveyed by a multi disciplinary team of scientists from Biodiversity and Resource Use Management between July and August 2008. Due to the fact that the Matlabas River rises within the Marakele National Park, the survey was coordinated through Dr A Deacon of SANParks. The team was also assisted by colleagues from the regional DWAF office. This was considered to be an exploratory survey, because none of the project team had any prior knowledge of the catchment and the most recent historical work had been conducted in this catchment by Kleynhans (1980). The 1980 survey only addressed the distribution of fish. There have been no assessments of any other ecological parameters. The flow regime of the river was poorly documented and the suitability of some biomonitoring methods was in question. A substantial amount of effort was expended in locating biomonitoring sites and in gathering local knowledge on the status quo of the river geomorphology, hydrology and ecology. A total of twelve sites were visited and conditions documented, but there was only flow at eight of these sites. The results of this biomonitoring survey should therefore be viewed with a low – moderate confidence. Where appropriate, the survey was conducted using standardized River Health Programme monitoring protocols with the objective of providing an assessment of the

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Eco-Status of the river. Six components were assessed using the following monitoring protocols. Geomorphology. Desktop study only. Fish (FRAI) Fish Response Assessment Index. Invertebrates (SASS5) South African Scoring System (version 5) Riparian Vegetation (RVI) Riparian Vegetation Index. Instream habitat (HQI) Habitat Quality Index. Invertebrate habitat. (IHAS) Invertebrate Habitat Assessment System. The data gathered during this survey, together with this ecological report provide a scientifically credible assessment of the State of the Environment (SOE) of the Matlabas Catchment. All monitoring protocols are recognized as National Indicators for the purposes of SOE reporting on aquatic ecosystems. The report may provide a valuable baseline for water resource managers in determining the Ecological Reserve of the Catchment and water licensing in terms of the National Water Act (1998). Results indicate that although the catchment was reeling from the effects of drought at the time of the survey, it still has a “Moderate” Ecological Importance and Sensitivity (EIS), largely due to the fact that a substantial portion of the catchment falls in Marakele National Park, private nature reserves or game farms.

The results of this survey also led to an assessment of the Eco Status of the catchment, which at this time places the entire catchment in a “Fair” Ecological Category. 1.2 Letaba River Catchment.

A biomonitoring survey of 14 representative sites in the Letaba River Catchment was completed in 2007. A technical report on the study was completed in February (Angliss 2008). Results have shown that the river remains in a “Fair” ecological category, although some survey sites remain in a better condition. Although previously expected, the red data fish Opsaridium peringueyi (Southern barred minnow) was recorded for the first time in this catchment. Furthermore, Chiloglanis engiops (Lowveld suckermouth) was reported extinct in the catchment in 2000, but it is heartening to report that it was found in moderate abundance during this survey. 1.3 Other river publications. A poster on the 2007 biomonitoring survey of the Nwanedzi River Catchment was produced in collaboration with the DWAF Polokwane office. A first ever joint publication. Other posters have been produced, which depict the fish which are found in specific rivers and reserves.

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2. The future of the River Monitoring in Limpopo Province. 2.1 State of Environment Reporting. As indicated above, the Biomonitoring Office of LEDET is tasked with the production of periodic State of Environment Reports. As a signatory to the Convention on Biological Diversity, South Africa is obliged to develop environmental indicators and to produce periodic State of Environment (SoE) reports. (Agenda 21: Rio Declaration) The responsibility for producing detailed environmental reports has been delegated to the provincial environmental authorities. It is then the responsibility of the national DEAT to provide the international community with a summarized national assessment. The first national assessment was completed in 1999. State of the Environment Reports, are intended to support sustainable development and decision-making through the provision of credible environmental information (Rump, 1996). SoE reporting plays an important role in assessing and interpreting data and making it readily available and meaningful to both decision-makers and the public, creating an important communication channel between scientists and the authorities. In Limpopo Province, Limpopo Environmental Affairs published an introductory, phase 1 SoER in 2004, while a more detailed, phase 2 report was published in 2006. In terms of aquatic monitoring, those indices developed by specialists at DWAF Resource Quality Services (RQS) and consultants, during the development phases of the River Health Programme, together with a structured monitoring strategy, are valuable indicators and provide some important information for the provincial SoER. 2.2. The River health Programme. Despite the fact that the original custodians of the RHP were DWAF, the Department of Environmental Affairs and Tourism (DEAT) and the Water Research Commission (WRC), the programme is strongly perceived to be a DWAF programme. The National Water Act requires that DWAF develops a fleet of monitoring programmes, one of which is the RHP. Since LEDET are driving river monitoring in the province, this leads to various conclusions, which suggest that the LEDET biomonitoring team is doing DWAF’s work. On the other hand, since the inception of the RHP, DWAF has demonstrated its inability to implement environmental programmes within the province. On the ground, the RHP is now being viewed as toothless window dressing which may be sending out conflicting messages to the public. Consider the following.

• 13 years into the programme, only 1 unqualified person is currently positioned to implement the programme in DWAF Polokwane.

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o >250 monitoring sites have been established, which are widely regarded as “DWAF sites”.

o >20% of our sites are regarded as DWAF National Monitoring sites. o With the exception of RQS specialists, nobody from DWAF has visited

any of these sites. • My management thinks I am doing DWAF public relations (PR) work. • The National RHP management has devolved from an effective DWAF Chief

Director to the current DWAF Assistant Director level that now focuses on PR work.

o Several provinces are now managed at the same level (rank) as the national programme.

• In most provinces the implementation of the RHP is far worse than in Limpopo Province. Only 4 provinces (Limpopo, Gauteng, North West and Western Cape) have viable monitoring teams, which are led by dedicated individuals.

In terms of managing ecological flows,

• There has been no progress in implementing the ecological Reserve in any of our rivers, yet countless Water Use Permits are being issued for golf course developments and to mining houses.

In terms of water quality.

• DWAF appear to have lost control in monitoring point source pollution. Raw Water discharges from sewage works are common place. The lack of

expertise at municipal sewage works is well documented, yet the problem persists with DWAF standing as impotent observers to the pollution.

• The DWAF office of Social and Ecological Studies has been disbanded. A new environmental office may develop in future, which will fall under the Engineering Directorate. (Pers. Com P. Ackerman of DWAF)

• Our systems are becoming more and more fragmented with DWAF developing weirs without referral to LEDET.

• Furthermore, the concept of the RHP, which shows that “Healthy Fish are indicators of a Healthy River Environment which in turn is indicative of Healthy People”, is contradictory, given the current cholera epidemic. We cannot be telling rural communities that the river is in a “good or fair” condition if there is a possibility of Cholera being present. A situation which is being amplified by the presence of raw sewage being discharged in many catchments. While other monitoring programmes may be addressing the monitoring of cholera, they clearly do not interlink with the RHP.

3. Conclusions. While the monitoring of aquatic indicators will continue, it is likely that our SoER’s will be documenting the decline in the state of our rivers. As an environmental department, we cannot condone the failure of DWAF to address the above issues. Nationally, the DWAF RHP appears to have become a public relations exercise and in Limpopo Province we need strong commitment and actions to conserve our riverine ecology and to inform the public of health risks.

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In terms of cooperative governance, LEDET will continue to support the RHP, through the provision of data, education and training, while distancing ourselves from the RHP corporate image, which we have strongly displayed in our work in the past. 4. References. Agenda 21 (1992). The Rio Declaration on Environment and Development. The

United Nations Conference on Environment and Development. Rio de Janeiro 1992.

Angliss MK. (2007). A Biomonitoring Survey of the Nwanedzi River Catchment,

Limpopo Province. Field Survey of 2006 – 2007. Internal report for Limpopo Dept. of Economic Development Environment and Tourism.

Angliss MK (2008). A Biomonitoring Survey Of Representative Sites Within The Letaba

River Catchment. Field Survey of 2007. Internal report for Limpopo Dept. of Economic Development Environment and Tourism.

Angliss MK. (2008). An Exploratory Biomonitoring Survey of The Matlabas River

Catchment, Limpopo Province. Field Survey of 2008. Internal report for Limpopo Dept. of Economic Development Environment and Tourism.

Department of Finance and Economic Development (DFED) (2004). Limpopo State of the Environment Report (phase 1). Compiled by African and Economics. Polokwane. Limpopo. South Africa.

Republic of South Africa (2004). National Environmental Management: Biodiversity Act (10 of 2004). Department of Environmental Affairs and Tourism. Pretoria.

Rump P. (1996). State of Environment Reporting: Source Book of Methods and Approaches. UNDP/DEIA. Report no. TR.96-1

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GAUTENG REPORT

Piet Muller Department of Agriculture, Conservation, Environment & Land Affairs, Box 8769, Johannesburg 2000.

Email: [email protected] Current Status of yellowfish in Gauteng Rivers: To date, no official fish surveys have been undertaken in the rivers of Gauteng except for a once-off survey of the upper Magalies River at Maloney’s Eye. This is mainly due to a shortage of skilled personnel, i.e. a fish specialist. Available data collected during the River Health Programme surveys at 74 sites over the last 9 years indicate that all 5 species; Labeobarbus marequensis, L. polylepis, L. kimberleyensis, L. aeneus and Barbus rapax, still occur in the rivers of the province. Although specimens of different ages were found, nothing is known about the ecological health of these populations. Yellowfish, as is the case for all other species, are under constant threat as result of the activities in the catchments such as increased urban sprawl, mining and industry as well as agriculture. The surface water runoff from these activities has a severe impact on both water quality, chemical and physical, as well as quantity. Irregular, modified seasonal flows through the untimely release of water from dams and barrages have had a severe impact on the breeding cycles of all the fish species in the rivers of Gauteng. Protection status of yellowfish in Gauteng: Primary protection - The legal protection of yellowfish in the province is covered in the form of the issuing of TOPS (Threatened or Protected Species) permits as well as angling licenses, which are put into place to protect the over utilization of the species. Although this is a prerequisite for all anglers and fishermen to adhere to, very few applications for permits and licenses are received annually! Illegal fish harvesting by subsistence fishermen by use of gill nets in rural areas is of grave concern and irregular inspections are undertaken by the law enforcement directorate to attempt to stop these destructive activities. Secondary protection – The implementation of the River Ecoclassification process for the determination of the EcoStatus of rivers by DWAF, will result in the ecological classification of all rivers which in turn will determine the seasonal flow requirements for the respective rivers. During this process, the ecological needs of all occurring fish species, including yellowfish are taken into account. This process which is imbedded in the National Water Act of 36 of 1998, lends protection to all the biota as well as the environment in which they have to survive. The implementation of the Gauteng Conservation Plan (C-Plan) in the province will in essence protect the sensitive catchments by means of setting strict requirements for development in sensitive catchments where rivers are still in a good to natural ecological state. The rationale behind this thinking is to prevent the impact of urban and industrial development on these rivers in order to protect the aquatic ecosystems which are still in

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a near natural state of functioning. Through this process, by maintaining the processes needed for yellowfish to survive (habitat and food), yellowfish will be protected. The 3 identified sensitive catchments in Gauteng include the natural occurrence of all 5 yellowfish species. Water quality: The surface water in most of the rivers in Gauteng is of poor chemical and physical quality mainly as result of the uncontrolled runoff from urban, industrial and agricultural development activities over the last 150 years. However, the implementation of the NWA in 1998, and through the issuing of water users licenses containing strict water quality and quantity conditions, to industries and local councils over the last 10 years is now starting to show results. A water quality trend analysis was done at 3 sites on the Blesbokspruit on the East Rand using water quality data donated by Rand Water. All indications are that the chemical water quality shows an improvement over time, but concerns over the increase in phosphates remain. Water quality data for the Upper Vaal is obtainable on the Rand Water website (www.reservoir.co.za ). Future impacts: The future need to meet the demand for water as result of the constant human population growth will have a grave impact on the natural aquatic ecosystems. The demand for water for the production of food, the generation of power for energy, the use of water for construction of houses, roads and industries, will grow exponentially along with the increase in human population to the extent that natural river and wetlands will act as aqua ducts to transport high volumes of water across catchments from one basin to another to cater for the ever-increasing demand for water. Conclusion: Although legislation is in place to protect aquatic ecosystems through wise use of water by all the sectors (basic human use – environmental use – international obligations – agricultural and industrial use), basic human rights in SA demand that all people have access to potable water. So, for that matter, the equation is simple. As long as there is an increase in human population there will be a primary demand for potable water (basic human rights). But what will happen if the demand for water exceeds the supply (basic human rights)? The answer is simple. As the population expands, more water is needed for human consumption, (basic human rights) less water will be available for the industries, international obligations, the environment to the point where no water will be available for human consumption! Basic human rights? And the Yellowfish? What’s that? There must come a point in time, soon, where a balance must be struck between human population growth and the limitations of the water resource to sustain such a population. At some point in time somehow, someone will have to stand up and promote human population regulation based on sound environmental principles, or will one species, Homo sapiens, with all its wisdom cause the total environmental collapse on the “Blue Planet”

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NORTHERN CAPE REGIONAL REPORT

Carl Nel 14 Scanlan St, New Park, Kimberley 8301. Email: [email protected]

Background: The predominantly arid Northern Cape and North-west provinces are home to two of South Africa’s seven true yellowfish species: Labeobarbus kimberleyensis (Orange-Vaal largemouth yellowfish) and Labeobarbus aeneus (Orange-Vaal smallmouth yellowfish), confined to the Orange, Vaal, Harts and Riet rivers. Despite their immense biodiversity, sport fishing and tourism value, the Northern Cape and Northwest provinces’ yellowfishes are increasingly under threat from anthropogenic impacts. Because of a fast growing sport and tourism industry and increased agricultural and mining development, it is likely that yellowfish will be subject to increased pressure in future. An awareness of the value of our yellowfish and the potential environmental problems - such as the destruction of riparian vegetation and in-stream habitat, physical barriers, water abstraction, pollution and enrichment of water resources, introduction of alien fishes, illegal gillnet and long line operations - will do much to change the fortune of these species. The NCYWG has been initiated to focus attention on the plight of these yellowfish species and implement remedial measures to ensure the continued existence of our yellowfish and its habitat Logo: Resembling the international CAR logo, with two arrows indicating “put back what you take out” Mission: To promote the conservation and sustainable use and management of yellowfish and its habitat in the Northern Cape and Northwest provinces Objectives: · To promote the conservation of the Northern Cape and Northwest’s yellowfish assemblage and its habitat · To participate in research and monitoring programs · To create awareness of our yellowfish amongst all water users · To address the needs, aspirations and problems of yellowfish anglers · To interact with land owners in the conservation of yellowfish as a species · To act in a consulting capacity in the planning of tourism activities · To influence policy and decision making at all levels

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Fish Tagging Programme: Example of conservation and tagging signs that can be found at our three established conservancies. Two on the Vaal at Christiana and below Warrenton and one at Lilydale on the Riet River – now part of Mokala National park (SANParks)

Fish tagging programme sign at Christiana

Our tagging programme was launched during the 2005 Bell’s festival at Christiana. We currently make use of the numbered UV tags inserted with an applicator by NW marine The database is updated as tags are used and whenever tagged fish are caught again. Currently only tracking movement and growth patterns as information gets updated Areas of tagging: Christiana, Vaal below Warrenton & Lilydale

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Threats: Mines not being rehabilitated.

Picture taken at Lilydale on the Riet river. Alluvial mining companies go bankrupt and leave everything as is. A lot can be done by enforcing DME and DWAF regulations w.r.t. EIA’s

One of our recent successes! Closed down barge mining after three months of operation on the Vaal at Barkly West.

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Fish traps in the Orange river below Vanderkloof dam. When water is released from the dam, the traps fill up and when the water recedes, the locals harvest these traps with any type of culling implement available – pangas, spears, pick handles, garden forks, etc. The dead fish including a large number of yellows are then sold in town for as little as R5 a fish! The farmer discovered this practice on his land and started levelling these traps with earthmoving equipment. This issue has also been brought to Pierre de Villiers attention via Dirk Human

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Illegal fishing nets are taken out of the river and burnt on almost every angling trip. This is an ongoing headache, but the number of nets being burnt hopefully puts some holes in the pockets of these illegal trappers, as most nets are not cheap home-made types.

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Sewerage Spills:

Taken at Christiana in September 2008, reported to local authorities who repaired within a few days. This is quite a frequent occurrence, but Christiana authorities do seem to heed our urgent calls to action. This sewer is in a vlei which runs down into the Vaal about 1km away and also affects the groundwater, especially during the rainy season.

Dilapidated sewer at Warrenton, next to the N12. The struggle at this site has been going on for over 6 years to get repairs done. Various reports to local authorities, but no-one seems to care. They are never available for contact or comment and don’t answer e-mails. Comparison since 2006. A new water scientist (Peter Ramollo) was appointed at DWAF’s Kimberley offices more than a year ago, and after several invitations to attend meetings and even a personal visit from myself, still no response or indication of involvement.

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A bilge pump supposed to pump raw sewerage to the processing plant about 2km away. Water leaking into a vlei (now almost a small river), flowing under the N12, through the town of Warrenton and into the Vaal which is less than 1km away. DEAT Kimberley became aware of this struggle through the “fishing owl website”, but still no word from them after replies to their initial mail: “I am with the Department of Tourism, Environment and Conservation’s Compliance and Enforcement Unit. When and where can I get in contact with you to discuss NCYWG’s concerns regarding the sewage spills in the Warrenton area? Please feel free to contact me at the numbers indicated below or on my email address.” Regards Obopeng Tokgamo Gaoraelwe Deputy Director: Compliance and Enforcement Department of Tourism, Environment and Conservation Private Bag X6102 Kimberley 8301 Tel: +27(53) 807 4800 Fax: +27(53) 831 3530 Cell: +27(82) 414 0310 email: [email protected]

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Our public awareness programme includes: Pamphlets and flyers at various points of interest Tourism offices, angling shops, schools, hotels & guesthouses and our annual Bell’s festival We also conduct educational programmes at schools Rely on information from club members and the public to act on threats

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YELLOWFISH POPULATIONS & RHP PROGRAMME REPORT IN NORTH WEST PROVINCE – 2009:

Daan Buijs & Hermien Roux Biodiversity Specialist Support Unit, Directorate Biodiversity Regulation and Conservation, NW Department of Agriculture, Conservation and Environment, PO Box 510, Zeerust, 2865, Email:

[email protected] and [email protected]

PART 1: YELLOWFISH POPULATION STATUS - Daan Buijs

Abstract Four Labeobarbus spp and Barbus rapax occur in four Water Management Areas in the North West province. Little yellowfish specific research is conducted in the province except for the work in the Vaal River. The efforts of the province regarding aquatic monitoring are focused on the River Health Programme, and some results are presented. Severe pollution and flow threats are experienced in the “work horse” rivers originating in industrial areas, namely the Vaal and Crocodile Rivers, while rural rivers experience problems caused by dams and erratic water release regimes, alien vegetation and limited mining activities. However, there are some near-pristine rivers in the upper reaches and these are of high biodiversity value.

Introduction Four water management areas (WMA) are present in the North West Province, namely the Upper, Middle and Lower Vaal River WMA’s in the south feeding into the west flowing Orange River and the Crocodile West and Marico WMA feeding into the east flowing Limpopo River in the north (Figure 1). The Vaal River WMA’s harbour two different yellowfish species and the Marico/Crocodile WMA contains two yellowfish species and the papermouth.

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Upper Vaal

Figure 1: Water Management Areas and yellowfish occurrence in the North West Province.

Species present Labeobarbus kimberleyensis and L. aeneus in the west flowing Vaal River system. L. marequensis, L. polylepis and B. rapax in the east flowing Marico/Crocodile River system. Rouhani (2004), in a survey of 10 large dams in the North West Province, recorded Labeobarbus kimberleyensis in the Taung dam, L. aeneus in the Taung and Koster dams and L. marequensis in Lindleyspoort, Vaalkop and Roodekopjes dams. Cochrane (1985) and Koekemoer & Steyn (2005) recorded L. marequensis in Hartebeespoort Dam. Barbus rapax was recorded in Hartebeespoort, Molatedi, Lindleyspoort, Vaalkop and Roodekopjes dams (Rouhani, 2004). Koekemoer, (2009) reported on a fish population study of selected dams in NW Province. Some of the results will be discussed. All the dams contained yellowfish (Table 1), but the occurrence of L. aeneus in Koster Dam is the result of stocking of the species into the Marico/Crocodile system where they do not naturally occur. (Rouhani (2004) reports that a Mr. Smith stocked yellow fish (though he was not aware which species) into Koster dam in 1995 from a hatchery near Hartebeespoort Dam. Mr. Smith mentioned that he did not have any permits for this, and was not sure if these fish were endemic to the catchment). These introduced fish seem to do well, being the second most abundant species in the dam.

N E W

S

NW W a ter Ma nagement AreasL. marequensisB. rapax L. polylepis

L. kimberleyensis L. aeneus

Middle Vaal

Marico Crocodile

Lower Vaal

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Table 1: Results of surveys of selected dams in NW Province (Koekemoer, 2009).

Number % Number

Ranking numbers

Mass (kg)

% Mass

Ranking mass

Koster Dam (August 2008)Labeobarbus aeneus 49 29.5 2 13.21 8.13 3 Total (all fish species) 166 6 162.59 6

Lindleyspoort Dam (September 2008)Barbus rapax 258 29.3 2 18.09 4.10 5 Labeobarbus marequensis 84 9.5 4 35.45 7.90 3 Total (all fish species) 880 445.97

Hartebeespoort Dam, 2004 (two surveys)Labeobarbus marequensis 540 8.5 3 80 13.2 2 Barbus rapax 70 1.1 8 4 0.7 7 Labeobarbus polylepis 20 0.3 9 2 0.3 8 Total (all fish species) 6390 606

Hartebeespoort Dam, April/May 2008Labeobarbus marequensis 134 8.0 3 30.41 10.5 3 Barbus rapax 18 1.1 7 5.48 1.9 6 Labeobarbus polylepis 1 0.1 9 0.098 0 Total (all fish species) 1673 289.69

Labeobarbus marequensis seems to be well adapted to dam conditions, with the highest ranking in Lindleyspoort Dam (9.5% of total number of fish caught). In Hartebeespoort Dam, L. marequensis ranked 3rd in numbers, between 8.0 and 8.5% of the total. It must be noted however that the average mass of this species was low (Table 2), but this may be biased because large numbers were caught in the gill nets with smaller mesh sizes. The large numbers of small fish does, however, indicate successful breeding. Labeobarbus polylepis only occurred in small numbers in Hartebeespoort Dam. Barbus rapax occurs in high numbers in Lindleyspoort Dam (29.3% of all fish collected), but to a much lesser extent in Hartebeespoort Dam. The study by Rouhani (2004) also found B. rapax to be the one of the dominant species in Molatedi, Lindleyspoort, Vaalkop and Roodekopjes dams. Table 2: Average mass (kg) of yellowfish collected by Koekemoer (2009).

Labeobarbus aeneus

Labeobarbus marequensis

Barbus rapax Labeobarbus polylepis

Koster Dam 0.27 Lindleyspoort 0.422 0.070 Hartebeespoort 2004 0.15 0.06 0.10 Hartebeespoort 2008 0.23 0.304 0.098

In the Taung Dam L. aeneus dominated the numbers of fish collected by Rouhani (2004) in terms of numbers (21.2/net/night), with Labeobarbus kimberleyensis ranked second (3.1/net/night). The lengths recorded by Rouhani (2004) are presented in Table 3.

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Table 3: Average length (cm) of yellowfish in selected dams in the North West Province (Rouhani, 2004) Labeobarbus

aeneusLabeobarbus

kimberleyensisBarbus rapax

Taung Dam 24.0 - 33.9cm (max 58cm)

26.0 - 47.9 cm (max 58cm)

Lindleyspoort Dam 21.7 ± 4.2cm (max 38cm)

Roodekopjes Dam 22.6 ± 5.7cm (max 38cm)

Koster Dam 18 – 24cm

(max 42cm)

Vaalkop Dam 23.8 ± 2.5cm (max 36cm)

Molatedi Dam 23.2 ± 5.9cm (max 40cm)

Status of species Labeobarbus kimberleyensis - Vulnerable (VU A1c)* (IUCN, 2004). *(A = Reduction in population size; 1 = an observed, estimated, inferred or suspected population size reduction of >50% over the last 10 years or three generations & c = a decline in area of occupancy, extent of occurrence and/or quality of habitat.) L. kimberleyensis is also listed as a Threatened or Protected Species under the regulations of the National Environmental Management: Biodiversity Act. The other species are not listed, but catch restrictions are imposed. Sub-populations present: Unknown Sub-populations status: Unknown Threats Annexure A reports on the anthropogenic impacts on the rivers in the NW Province which pose a serious threat to aquatic biota. Another cause for concern is the illegal distribution and stocking of fish species, including yellowfish, as the introduction of L. aeneus into Koster Dam clearly illustrates. This practice not only results in the introduction of species alien to specific ecosystems, but can also be a source of genetic pollution and disease. Man-made impoundments reduce natural spawning sites, which may cause different species to congregate at the remaining suitable sites at the inflow of the river. This can lead to hybridization, as is suspected between L. aeneus and L. kimberleyensis in Taung Dam. Conservation measures to conserve yellowfish resource Conservancies – Orange Vaal River Yellowfish Conservation and Management Association

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Stockings – None by NW DACE, but illegal stocking by private individuals have been reported (Labeobarbus aeneus in Koster Dam). Education and awareness – Wetland Awareness Campaign by North West Wetland Forum, Crocodile (West)/Marico State of the Rivers Report and Poster. Legislation – New provincial angling license conditions have been approved by the MEC and are currently at the Government Printers for gazetting. Table 4: New bag limits for the North West Province Species Bag limit Minimum size (Fork length) L. kimberleyensis Catch and release only N/AL. aureus 2 300mmL. marequensis 4 300mmL. polylepis 2 300mm Monitoring - The National River Health Programme (RHP) is included in the Strategic Plan of NW DACE. Although not aimed specifically at yellowfish, the programme monitors the biodiversity at selected sites with different indices (including SASS5 and VEGRAI) and also (but currently to a lesser extent) includes fish surveys. A progress report is attached (Annexure A) Research – No yellowfish-specific research is done by NW DACE. J.H. Koekemoer is conducting a Ph.D. study on fish population structures in Hartebeespoort Dam, Lindleyspoort Dam and Koster Dam (see results under “Species present”). The University of Johannesburg and the Endangered Wildlife Trust are conducting research on yellowfish in the Vaal River. Intermediate Ecological Reserve determinations are in progress for the all four Water Management Areas in NW (commissioned by DWAF). Action plan & Progress Report - The Conservation Plan for the Crocodile (West) and Marico Rivers will be integrated in provincial biodiversity conservation strategy and bioregional plans. Value of yellowfish resource to anglers and subsistence fishers No data available. Concluding remarks The rivers in North West are, as in the rest of South Africa, under severe threat from urban development, mining and agriculture. This has a severe impact on yellowfish populations, but fortunately there are still several river reaches in the higher lying areas that are in near pristine condition and with high biodiversity values. The NW province is a stronghold for L. marequensis and thanks to research projects and conservation endeavours of FOSAF and the Orange Vaal River Yellowfish Conservation

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and Management Association, L. kimberleyensis and L. aeneus receive attention. There is concern regarding the status of L. polylepis and a more intense survey of its preferred habitat is required. Acknowledgements Paul Fouche is thanked for conducting two fish surveys for the RHP in the North West Province and for the training given to our field staff. Johan Koekemoer is thanked for making his preliminary data available to NW DACE for this report. References Cochrane, K.L. 1985. The population dynamics and sustainable yield of the major fish

species in Hartbeespoort Dam. Ph.D.-Dissertation, University of the Witwatersrand, Johannesburg.

De Villiers, A.J. 1983. Vis populasie opname uitgevoer by die Molopo Oog: Lichtenburg

Distrik. Unpublished report quoted in Skelton et al 1994. IUCN 2004. 2004. IUCN Red List of Threatened Species. www.iucnredlist.org Kleynhans, C.J. & Louw M.D. 2006. River Ecoclassification: Manual for Ecostatus

Determination (Version 2). Department of Water Affairs & Forestry, Resource Quality Services, Pretoria Water for Africa, Pretoria.

Koekemoer, J.H. & Steyn, G.H. 2005. Final Report: Fish Community Study of

Hartebeespoort Dam. North West Department of Agriculture, Conservation & Environment.

Koekemoer, J.H. 2009. Interim Results of the First Fish Surveys (Early Summer) for the

Second Set of Dams. Part of the WRC Project No: 1643 Koekemoer, J.H. and Steyn, G.J. 2009. Interim Results of the First Fish Survey (Late

Summer) for Hartebeespoort Dam, 2008. Rouhani, Q. 2004. A report on the survey of selected dams in the North West Province: with a view to

develop fisheries. Report for the Department Of Agriculture, Conservation and Environment, North West Province, South Africa.

Skelton, P. 2001. A complete guide to the freshwater fishes of southern Africa. Struik Publishers,

Cape Town, South Africa. Skelton, E., A.J. Ribbink & V. Twentyman-Jones. 1994. The Conservation of Dolomitic

Ecosystems in the Western Transvaal, South Africa. JLB Smith Institute of Ichthyology, Grahamstown. 81pp.

Smith-Adao, LB., Nel, JL., Roux, DJ., Schonegevel, L., Hardwick, D., Maree, G., Hill, L.,

Roux, H., Kleynhans, CJ., Moolman, J., Thirion, C. and Todd, C. 2006. A Systematic Conservation Plan for the Freshwater Biodiversity of the Crocodile (West) and Marico Water

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YELLOWFISH POPULATIONS & RHP PROGRAMME REPORT IN NORTH

WEST PROVINCE – 2009

Daan Buijs & Hermien Roux PART 2: NW RIVER HEALTH PROGRAMME REPORT, JAN. 2005 TO MARCH

2009 – Hermien Roux

Table of Contents Page 1 Introduction 1182 Background 1183 Biomonitoring indices used 1194 Monitoring 1215 Upper Vaal Water Management 1226 Middle Vaal Water Mangement 1257 Lower Vaal Water Managemennt 1288 Molopo, Marico River and tributaries 1319 Elands River and tributaries 13810 Hex and Sterkstroom Rivers 14111 Crocodile River and tributaries 14312 Conclusion 14713 References 147 List of Figures Page Figure 1 Water management Areas in the North West Province 119Figure 2 Distribution of Biomonitoring sites and Ecoregions in the Province 121Figure 3 SASS5 sites in the Upper Vaal WMA 123Figure 4 SASS5 sites in the Middle Vaal WMA 126Figure 5 SASS5 sites in the Lower Vaal WMA 129Figure 6 Molopo River Sites 133Figure 7 Marico River Sites 134Figure 8 Elands River Sites 139Figure 9 Hex and Sterkstroom River Sites 142Figure 10 Crocodile River Sites 144 List of Tables Page Table 1 Summary of major indices used in the NW River Health Programme 120Table 2 Summary of IHI and SASS5 Ecological class results for the Upper Vaal 124Table 3 Summary of IHI and SASS5 Ecological class results for the Middle Vaal 127Table 4 Summary of IHI and SASS5 Ecological class results for the Lower Vaal 130Table 5 Summary of IHI and SASS5 Ecological class results for Molopo &

Marico Rivers 135

Table 6 Summary of IHI and SASS5 Ecological class results for Elands River 140Table 7 Summary of IHI and SASS5 Ecological class results for Hex

& Sterkstroom Rivers 143

Table 8 Summary of IHI and SASS5 Ecological class results for Crocodile River 145

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1 Introduction The purpose of this document is to provide a brief report on the progress of the Provincial River Health Programme (RHP) in the North West Province since 2005. The origin and background of this programme will also be discussed. Progress with the monitoring programme in the different biomonitoring regions, linkages to other projects and a summary of products will be provided. 2. Background The River Health Programme is a subprogramme of the National Aquatic Ecosystem Health Monitoring Programme (NAEHMP). The national custodians of the National Aquatic Ecosystem Health Monitoring Programme (NAEHMP) are: The Department of Water Affairs and Forestry (DWAF), Department of Environmental Affairs and Tourism (DEAT) and the Water Research Commission (WRC), that provide strategic guidance and direction to the Programme. The Programme is administered and coordinated by DWAF’s Directorate: Resource Quality Services and have to date, been assisted by the CSIR to fulfill this role. The River Health Programme (RHP) was initiated on a national basis in 1994 in response to the need to monitor, assess and report on the ecological state of river ecosystems based on their biological condition in relation to anthropogenic influences. The RHP is coordinated on a national level and implemented on a provincial level throughout the country. The River Health Programme monitors and assesses the biological and habitat integrity of rivers (through evaluation of, for example, aquatic invertebrates, diatoms and riparian vegetation). These assessments enable reports on the ecological state of river systems to be produced in an objective and scientifically sound manner.

Why monitor?

We have legal obligations (National Water Act and various other conservation and environmental legislation, NEMA, NEMBA) to monitor the ecological condition of natural resources.

If you have to manage something, you have to know where, how much of it and in what condition it is.

Assess the general ecological state Assess impacts Assess compliance with ecological objectives/ regulatory standards Trend detection (in other words, directional changes in attributes of drivers and

biota)

The North West team is responsible for biomonitoring in parts of four water management areas (WMA), namely; Crocodile (West) and Marico, Upper-, Middle- and Lower Vaal Water Management Areas (see Figure 1). The WMA’s are further subdivided into 7 biomonitoring regions. The Crocodile West and Marico is divided into four biomonitoring areas: Marico and Molopo; Western Crocodile (Elands river and tributaries), Middle Crocodile (Hex and Sterkstroom) and the Eastern Crocodile

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(Crocodile, Pienaars, Tolwane and tributaries). The Lower, Middle and Upper Vaal each form a separate biomonitoring region.

Figure 1: Water Management Areas in the North West Province 3. Biomonitoring indices used Biota in riverine ecosystems reflect both the present and past history of the water quality at a particular point in the river, allowing detection of disturbances that might otherwise be missed (Eekhout et al., 1996). Aquatic communities (e.g. fish, riparian vegetation, macro-invertebrates) can integrate and reflect the effects of chemical and physical disturbances that occur in river ecosystems over extended periods of time. These communities can provide a holistic and integrated measure of the integrity or health of the river as a whole (Barber-James, 2001; Roux, 2001). Walmsley et al. (2001) stated that indicators could provide measurements of the success of integrated water resource management. Methods have been developed for the bioassessment of the integrity of aquatic systems that are based on some or other aspect of a single species, but most are based on the attributes of whole assemblages of organisms. Examples of such indicators include the Fish Assemblage Integrity Index (Kleynhans, 1999), the Riparian Vegetation Index as well as the South African Scoring System, better known as SASS (Chutter, 1998). Although some methods have been available for many years, biomonitoring has only recently become a routine tool in the management of South Africa’s inland waters (Davies & Day, 1998). The SASS biomonitoring system has gained a large body of support as a rapid and fairly accurate system of evaluating ecosystem health and is currently in its fifth revised state, namely SASS 5 (Dickens and Graham, 2002). Table 1 provides a summary of the biological indicator indices that are used in the RHP. The person responsible and the activity status are also mentioned. There are other indices that also form part of aquatic monitoring, these are not used due to capacity constraints. The two main indices currently used in the NW RHP are the Index of Habitat Integrity (IHI) and SASS5.

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Table 1: Summary of major indices used in the North West River Health Programme

Tools Used in NW RHP

Reason

SASS5 (South African Scoring System 5) andMIRAI (Macro Invertebrate Rapid Assessment

Index)

Yes Accredited person: H.Roux

VEGRAI (Riparian Vegetation Response Assessment Index)

Yes Botanist (started 2007): A. Barac

FRAI (Fish Response Assessment Index) NO butSometimes

No Ichthyologist

IHI (Index of Habitat Integrity) IHAS (Invertebrate Habitat Assessment System)

Yes, selected riversYes

H. Roux and consultants H. Roux

GAI (Geomorphologic Driver Assessment Index) and HAI (Hydrological Driver Assessment Index)

Yes- basic info H. Roux

PAI (Physico-chemical Driver Assessment Index) No, only basic water quality data

and samples

PAI still under development H. Roux (future links to

ambient monitoring) Diatoms Yes Field staff (collect)

J. Taylor (ID analyze)

Basic site information and database Yes H. Roux

Data from the various indices are analysed to provide an indication of the ecological status or class of the rivers/ biomonitoring sites in the province. The ecological status of a river is defined as the “totality of the features and characteristics of the river and its riparian areas that bear upon its ability to support an appropriate natural flora and fauna” (adapted from Iversen et al 2000). Ecological components include: Hydro-morphology (Geomorphology and Hydrology) (Driver); Water quality (Driver); Physical habitat (Driver); Biological groups (Biological responses of fish, riparian vegetation and aquatic invertebrates). The river type (geomorphology very important) and the resilience, adaptability and fragility of the biota will influence how responses to changes are analysed. The importance of the different driver metrics will thus change as the river type changes (weighting and ranking of metrics). The cause and effect relationship becomes very important during reserve determination, monitoring of the reserve in terms of monitoring compliance and systematic conservation planning. The present condition of the drivers needs to be assessed and interpreted in terms of the biological habitat and then the biological responses compared to a reference condition Ecostatus approach. All of the indices use the same classification system for the Ecostatus approach. The results from the indices can be represented as A (Blue) to F (Red) classes, based on the degree of impacts or deviation from reference condition:

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4. Monitoring In total 178 RHP sites are monitored across the province. These sites are registered on the National Rivers Database and on the DWAF Water Management System database. There are currently 277 sets of SASS5 (South African Scoring System version 5) and Site Information data captured to the National Rivers Database for monitoring results since 2005. Each site is monitored at least twice a year, every second year, if environmental parameters are favorable for the application of SASS5. Figure 2, provides an indication of the RHP biomonitoring site distribution in the province. Diatoms are collected and analyzed by the North West University (Jonathan Taylor). Basic water quality parameters are measured and water quality samples collected and analyzed by DWAF RQS. The botanist is training to do the Riparian Vegetation Analyses and has completed the preliminary evaluations at some of the biomonitoring sites.

Figure 2: Distribution of biomonitoring sites and Ecoregions in the Province The SASS5 procedure requires that the practitioner is accredited every three years to ensure data credibility and repeatability of the methodology, the correct identification of the aquatic invertebrates is vital for the application of the biomonitoring technique. Annual biomonitoring plans are distributed to the RHP team and relevant stakeholders to encourage shared resources. Feedback is also provided to stakeholders after each biomonitoring fieldwork session. Field data forms are completed at each site, scores calculated and data captured to MS Excel spreadsheets and to the National Rivers Database. Data analysis is done as per requirements for reporting purposes. The results from the different biomonitoring will be discussed separately and major issues identified will be discussed.

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5. Upper Vaal Water Management Area The Mooi River originates in a dolomitic area upstream from Klerkskraal Dam in the Upper Vaal Water Management Area, see Figure 3. The groundwater in the area is widely utilised for irrigated agriculture. The SASS5 data are from two surveys in 2006 (May and October), biomonitoring was planned for 2008 but kilometre restrictions by NW-DACE prevented the surveys. The upper reaches of the river above and below the Klerkskraal Dam comprise of wetlands. The Klerkskraal Dam distributes water to farmers downstream of the dam for irrigation purposes. This substantially reduces both the variability and volume of water that occurs in the system downstream of the dam. No releases are being made from the Klerkskraal Dam for the Ecological Reserve. The biological data reflects this and the area upstream from Potchefstroom is in an overall C Ecological class and the IHI category is overall a D class, mostly due to old unreabilitated diamond mines and crop farming, see Table 3. The sites are all situated in the Highveld Ecoregion. The Wonderfonteinspruit and Loopspruit are two tributaries of the Mooi River that originate east of the Mooi River. Mine water contamination (including heavy metals) from the Wonderfonteinspruit is a serious concern, no suitable SASS5 habitat exists but water samples were collected in the Wonderfonteinspruit at site C2WOND-WONDE. Peat mining takes place in the Gerhard Minnebron wetland, diamond mining and prospecting has taken place in areas below Klerkskraal Dam and has impacted on the riverbed and riparian zone. The Loopspruit SASS5 data indicate serious sewerage pollution and flow problems (site C2LOOP-KOKOS), the Ecological class is predominantly F. The IHI class is mostly D, return flows from flood irrigation and cattle carcasses dumped in the river were observed. The raising of the Klipdrift Dam (site C2LOOP-KLIPD) in the middle reaches enhances the deterioration by reducing flow events. Potchefstroom Dam and town are situated in the lower reaches of the Mooi River, adding additional habitat modifications to the river. The SASS5 data indicate a C/D class (sites C2MOOI-MEULS and C2MOOI-MOOIR) and a reduction in sensitive taxa, the IHI class is D. The Vaal River is a heavily utilised system and is impacted by various activities in the Gauteng, North West and Free State provinces. The primary impact on the river system is the deterioration of water quality as a result of salinisation and eutrophication of the system, and flow modification. The SASS5 biomonitoring data indicate a low C Ecological class; the water quality deteriorated below Parys during October 2006 and recovered through the Vredefort Dome area, the overall IHI results in a C class.

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Sk o

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Mooirivierloop

Enselspruit

Wonderfonteinspruit

Taaibosspruit

Kaalspruit

Riet

gatsp

rui t

Vaal

Mooi

C2MOOIKLER

C2MOOIROOI

C2WONDWOND

C2OOGGOOGG

C2MOOIRYSM

C2MOOIOUDE

C2MOOIMEULC2MOOIMOOIC2MOOIGHOL

C2LOOPWELTC2LOOPKOKO

C2LOOPTAAI

C2LOOPKLIPC2LOOPMILI

C2VAALPARYC2VAALSTONC2VAALELGR

C2VAALKNOP

30 0 30 60 Miles

Dams500g_rsa.shp# Sites_2009_gis.dbf

Nw new border.shp

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Figure 3: SASS5 sites in the Upper Vaal WMA

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Table 2: Summary of Index of Habitat Integrity and SASS5 Ecological class results for the Upper Vaal

RHP Site Code River Name

Tributary

IHI Instream 2007

IHI Riparian 2007

Survey dates

SASSNo Taxa

ASPT

Survey dates

SASS No Taxa ASPT

C2MOOI-KLERK Mooi D D 15/05/200

6 123 27 4.56 03/10/2006 92 22 4.18

C2MOOI-ROOID Mooi D D 15/05/200

6 79 19 4.16 Visit on 03/10/2006, river dry

x x x

C2WOND-WONDE

Mooi Wonderfonteinspruit

C D 15/05/2006 x x x 03/10/2006 x x x

C2OOGG-OOGGE

Mooi Oog van Gerhard Minnebron

C C 16/05/2006 141 25 5.64 03/10/2006 134 25 5.36

C2MOOI-RYSMI Mooi

C D 16/05/2006 129 25 5.16

Visit on 03/10/2006, very high water levels

x x x

C2MOOI-OUDED

Mooi

E F 16/05/2006 115 22 5.23

Visit on 04/10/2006, access problems

x x x

C2MOOI-MEULS Mooi D D 16/05/2006 56 14 4 04/10/2006 144 30 4.8

C2MOOI-MOOIR

Mooi D D 19/05/2006 91 21 4.33 04/10/2006 109 22 4.95

C2MOOI-GHOLF

Mooi

D D

Visit on 19/05/2006, water levels very high

x x x

Visit on 04/10/2006, very high water levels

x x x

C2LOOP-WELTE Mooi Loopspruit 17/05/200

6 105 22 4.77 02/10/2006 121 26 4.65 C2LOOP-KOKOS

Mooi Loopspruit D C 17/05/200

6 27 8 3.38 02/10/2006 29 8 3.63 C2LOOP-TAAIB Mooi Loopspru

it C C Visit on 19/05/2006, no veg

x x x Visit on 02/10/2006. no veg

x x x C2LOOP-KLIPD Mooi Loopspru

it F F 17/05/200

6 46 13 3.54

Visit on 02/10/2006, increasing dam wall no water

x x x

C2LOOP-MILIT Mooi Loopspruit

D D 17/05/2006 x x x

Visit on 02/10/2006, increasing dam wall no water

x x x

C2VAAL-PARYS Vaal C C 18/05/2006 130 24 5.42 05/10/2006 110 25 4.4

C2VAAL-STONE Vaal C C 18/05/2006 136 25 5.44 Visit on

05/10/2006 x x x C2VAAL-ELGRO Vaal C C x x x 05/10/2006 126 27 4.67C2VAAL-KNOPF Vaal

D D

Visit on 18/05/2006, high water levels

x x x Visit on 05/10/2006 x x x

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6. Middle Vaal Water Management Area This water management area is characterized by various seasonal rivers. The only river that could be sampled during February and November 2007 was the Skoonspruit and one site on the Vaal River, see Figure 4. This water management area is thus fairly data deficient and difficult to discuss. The Skoonspruit River originates north of the town of Ventersdorp as a dolomitic eye, peat wetlands are associated with these upper reaches, see Figure 4. It contributes to the flow in the upper parts of the catchment and flows south to the confluence with the Vaal River. The IHI and SASS5 data indicate a high C Ecological class in the upper reaches of the Skoonspruit (site C2SKOO-VENTE), see Table 4. The sites are all situated in the Highveld Ecoregion. The topography is gentle sloping. A wetland system occurs in the middle reaches of the river, in the vicinity of the confluence with the Taaiboschspruit and upstream from the Johan Neser Dam. Water abstraction is a major impact upstream from the Johan Neser Dam. The SASS5 data reflect the water abstraction and thus flow limitations as the Ecological classes are high E/F (major sedimentation buildup due to lack of flow) and C during different biomonitoring surveys. The IHI results indicate a C/D class, also mainly attributed to flow alterations. The Johan Neser Dam receives return flow from the mining areas. The biomonitoring point at Uraniumville (C2SKOO-URANI) is situated below sewerage treatment facilities, the SASS5 data indicate an E/F class, mainly attributed to water quality impacts from nutrient enrichment. The corresponding IHI results are a D class, with river and riparian modifications resulting from development as the main contributors.

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C2SKOOHART

C2SKOOWITP

C2SKOOURAN

C2JAGSOORBC2JAGSRIET

C2JAGSAFRIC2JAGSWOLW

C2JAGSGOED

C2YSTEORKNC2MATJSTRY

C2MATJMATJC2KLIPLEEU

C2KLIPSYFEC2LEEUSYFE

C2MAKWFRIS

C2MAKWPALMC2UNSPSYFE

C2MAKWBRAN

C2MAKWVLIE

C2BAMBRIET

C2BAMBPOOR

C2BAMBKARE

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Moo

i

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Kl ip spru it

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Bam

boes sp r ui t

Ystersprui t

Taaibosspruit

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Makw

ass ies pru it

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Kaalspruit Koekemoersprui t

Kro

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a ai s

p ru i

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Leeudor ings pru it

SlypsteenspruitRietspruit

Vaal

Vaal

50 0 50 100 Miles


Nw new border.shp

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Figure 4: SASS5 sites in the Middle Vaal WMA

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Table 3: Summary of Index of Habitat Integrity and SASS5 Ecological class results for the Middle Vaal


Tributary of

IHI Instream 2007

IHI Riparian 2007

Survey dates

SASSNo Taxa

ASPT Survey dates

SASS No Taxa

ASPT

C2VAAL-VERMA Vaal 19/02/2007 100 20 5 28/11/2007 111 23 4.83

C2KROM-RIETK Kromdraaispruit

Koekemoerspruit

20/02/2007 Dry

x x x No flow on 28/11/2007 x x x

C2SKOO-VENTE Skoonspruit

Vaal C C 21/02/2007 No flow

x x x 26/11/2007 164 33 4.97

C2SKOO-RIETS Skoonspruit

Vaal C D 20/02/2007 Pools

x x x 26/11/2007 101 23 4.39

C2TAAI-SHEFF Taaibosspruit

Skoonspruit 20/02/2007 Dry

x x x Dry on 28/11/2007 x x x

C2TAAI-NOOIT Taaibosspruit

Skoonspruit 20/02/2007 Pools

x x x Pools on 28/11/2007 x x x

C2SKOO-HARTB Skoonspruit

Vaal C C 20/02/2007 No Flow

x x x 27/11/2007 118 25 4.72

C2SKOO-WITPO Skoonspruit

Vaal D D 20/02/2007 No Flow

x x x No SIC on 27/11/2007 x x x

C2SKOO-URANI Skoonspruit

Vaal D D 19/02/2007 35 11 3.18 27/11/2007 37 10 3.7


Tributary of

IHI Instream 2007

IHI Riparian 2007

Survey dates

SASSNo Taxa

ASPT Survey dates

SASS No Taxa

ASPT

C2JAGS-OORBI Jagspruit Skoonspruit 20/02/2007 No Sic

x x x No Sic on 27/11/2007 x x x

C2JAGS-RIETK Jagspruit Skoonspruit 20/02/2007 Dry

x x x

Pollution from mine? On 28/11/2007

x x x

C2JAGS-AFRIK Jagspruit Skoonspruit Fish site x x x

low flow (fish site) on 28/11/2007

x x x

C2JAGS-WOLWE Jagspruit Skoonspruit 20/02/2007 Dry


C2JAGS-GOEDG Jagspruit Skoonspruit Fish site x x x

Pools (fish site) on 27/11/2007

x x x

C2YSTE-ORKNE Vaal Ysterspruit 20/02/2007 Dry


C2MATJ-STRYD Matjiesspruit

Vaal 20/02/2007 Dry

x x x Dry on 27/11/2007 x x x

C2MATJ-MATJE Matjiesspruit

Vaal 20/02/2007 Pools

x x x Pools on 27/11/2007 x x x

C2KLIP-LEEUW Klipspruit Vaal 20/02/2007 Pools

x x x Dry on 27/11/2007 x x x

C2KLIP-SYFER Klipspruit Vaal 20/02/2007 Dry

x x x Dry on 27/11/2007 x x x

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7. Lower Vaal Water Management Area The sites in this water management area are distributed across three different Ecoregions: Highveld, Ghaap Plateau and Southern Kalahari. The Harts River originates south of Lichtenburg, the upper parts of this river are highly seasonal as indicated by Table 5. There are major impacts from farming and diamond mining in the river channels. The Harts River forms part of a major irrigation scheme and water transfers are made from the Vaal River. It is unfortunate that an aerial survey and IHI was not done for this water management area. There are several seasonal tributaries and rivers in this Water Management Area, see Figure 5. The site downstream from the Taung Dam (C3HART-TOLGA) is in a B/C Ecological class, no ecological flow releases are made. The C Ecological class was during very low flow conditions in April 2007 and the improved class B was after rain in December 2007. The situation in and below Taung deteriorates to a C/D Ecological class (sites C3HART-HOSPI and C3HART-TASUN) sewerage enrichment and urban runoff are contributing factors. The lower class was in April 2007 and the slight improvement was in December 2007 after rain. The sites upstream from the major irrigation area shows an improvement from the sites in Taung, these sites are in a high C Ecological class (C3HART-MOTSW, C3HART-PAMPI). Wetland areas parallel to the Harts River downstream from Taung are important features of the river system.

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art s

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arts

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Pudumong

Thut lwan e

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Do rin gl aa gte

Blue Pool

Barberspan

Khudunkgwelaagte

Bergspruit

Sepane

Langasemspruit

Ran golw ane

Mo rokwa

Gan

yesa

Pha

posa

n e

Disipi

Tlhalatau

Mosi ta se Laa gte

Biesieslaagte

Wolwespruit

Korobela

Bloemhof

Spitskop

Barberspan

Taung

Leeupan279IO

Schweitzer Reneke

C3HARTRIETC3HARTKARE

C3HARTSOOI

C3HARTSAVI

C3HARTSANN

C3KLEIWOLW

C3KLEIUITS

C3KLEIHARTC3KLEIFISH

C3HARTWELG

C3HARTBARB

C3HARTMIGD

C3HARTJALA

C3HARTSSCH

C3HARTGOUD

C3HARTNOUP

C3HARTADAMC3HARTTOLG

C3HARTTASUC3BLUENORL

C3UNSPTHOMC3HARTMOTS

C3HARTPAMP

C3HARTKGOM

D4MOSHDITH

D4MOSHSETH

60 0 60 120 Miles


Nw new border.shp

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Figure 5: SASS5 sites in the Lower Vaal WMA

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Table 4: Summary of Index of Habitat Integrity and SASS5 Ecological class results for the Lower Vaal


Tributary IHI Instream 2007

IHI Riparian 2007

Survey dates SASSNo Taxa

ASPT Survey dates SASS No Taxa

ASPT

C3HART-RIETF Harts Vaal Dry on 18/04/2007 x x x Pools, no flow

on 7/12/2007 x x x

C3HART-KAREE Harts Vaal Fish site x x x Fish site x x x

C3HART-SOOIH Harts Vaal Dry on 18/04/2007 x x x Pools, no flow

on 7/12/2007 x x x

C3HART-SAVIS Harts Vaal Fish site x x x Fish site x x x

C3HART-SANNI Harts Vaal Dry on 18/04/2007 x x x Pools, no flow

on 7/12/2007 x x x

C3KLEI-WOLWE Klein-Harts

Harts Fish site x x x Fish site x x x

C3KLEI-UITSC Klein-Harts

Harts Pools on 18/04/2007 x x x Pools, no flow

on 7/12/2007 x x x

C3KLEI-HARTS Klein-Harts

Harts Pools on

18/04/2007 x x x Pools, no flow on 7/12/2007 x x x

C3KLEI-FISHD Klein-Harts

Harts Fish site x x x Fish site x x x



IHI Riparian 2007



ASPT

C3HART-WELGE Harts Vaal

Dry on 18/04/2007 x x x Dry on

07/12/2007 x x x

C3HART-BARBE Harts Vaal Dry on

18/04/2007 x x x Dry on 07/12/2007 x x x

C3HART-MIGDO Harts Vaal Pools on

18/04/2007 x x x Flood conditions on 07/12/2007

x x x

C3HART-JALAJ Harts Vaal Pools on 18/04/2007 x x x Pools, no flow

on 7/12/2007 x x x

C3HART-SSCHW Harts Vaal Pools on 18/04/2007 x x x Dry on

07/12/2007 x x x

C3HART-GOUDP Harts Vaal

Pools on 18/04/2007 x x x

Flood conditions on 07/12/2007

x x x

C3HART-NOUPO

Harts Vaal Fish site x x x Fish site x x x

C3HART-ADAMW

Harts Vaal Fish site x x x Fish site x x x



IHI Riparian 2007



ASPT

C3HART-TOLGA Harts Vaal 17/04/2007 99 20 4.95 06/12/2007 138 31 4.45

C3HART-HOSPI Harts Vaal 17/04/2007 43 9 4.78 06/12/2007 98 22 4.45

C3HART-TASUN Harts Vaal 17/04/2007 63 16 3.94 06/12/2007 79 20 3.95

C3BLUE-NORLI Blue Pool

Harts Dry on 17/04/2007 x x x Dry on

05/12/2007 x x x

C3UNSP-THOME Unspecified

Harts Very low flow

on 17/04/2007 x x x very low flow on 05/12/2007 x x x

C3HART-MOTSW Harts Vaal Very low flow

on 16/04/2007 x x x 05/12/2007 119 28 4.25



IHI Riparian 2007



ASPT

C3HART-PAMPI Harts Vaal 16/04/2007 121 25 4.84 05/12/2007 109 24 4.54

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IHI Riparian 2007



ASPT

C3HART-KGOMO

Harts Vaal x x x Fish site x x x

D4MOSH-DITHA Moshaweng

Kuruman Very low flow on 16/04/2007 x x x Not in Province x x x

D4MOSH-SETHA Garamokwena

Moshaweng 16/04/2007 102 23 4.43 Not in Province x x x

Crocodile West and Marico Water Management Area (biomonitoring regions separate) 8. Molopo, Marico River and tributaries The Molopo River originates east of Mafikeng from a dolomitic eye and flows through the Mafikeng town complex towards the Botswana border, see Figure 6. Water is abstracted directly from the Molopo dolomitic eye for domestic use in Mafikeng. The extensive peat wetlands and underground water connections do not create ideal SASS5 habitat. The E/F Ecological class at D4MOLO-BUHRM is only a reflection of the habitat limitations and not the water quality, see Table 6. Rehabilitated wetland areas in the Mafikeng Nature Reserve, where alien vegetation has been removed, and bank and bed stabilisation works have been undertaken play an important ecological function in the river system. Major water abstractions take place in and downstream of Mafikeng from various dams. No release mechanisms or operating rules exist to release water from the major dams in the system. The sewerage treatment facility upstream from the site D4MOLO-MAFIK is responsible for the very low E/F Ecological class. Nutrient enrichment of the system is a serious threat. The importance of wetlands for water quality purification is noted by the improvement at site D4MOLO-LOMAN (D/EF). The Ecological class below Modimola dam (D4MOLO-MODIM) improves to a C. Erosion of the catchment and lack of ecological flow releases impact on the seasonal river reach downstream. Marico River and tributaries The Marico River system comprises of the Groot Marico and Klein Marico rivers. The Klein Marico River includes the Molemane and Kareespruit tributaries, see Figure 7. The Molemane comprises of extensive wetland and underground systems, the site (A3MOLE-OTTOS) at Ottoshoop is situated downstream from a predator farm. The site lacks some of the suitable SASS5 habitat and was in a high C Ecological class during March 2007, possible nutrient enrichment from the predator farm, deteriorated the class to an E/F in August 2007. The Molemane River originates from a dolomitic eye. Water is diverted from the dolomitic eye for domestic use. The upper parts of the river are impacted by a number of weirs and structures that are used for diversion of water and recreational purposes. The Kareespruit below the Zeerust golf course (A3KARE-GHOLF) and upstream from the sewerage treatment facility (A3KARE-RAILW) is in a D/EF Ecological class, the situation deteriorates below the sewerage treatment facility to an E/F class (A3KARE-ABJAT). Raw sewerage discharges and other nutrient inputs have severely deteriorated

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the water quality in the Klein Maricopoort Dam. The dam acts as a nutrient trap and the site downstream from the dam (A3KMAR-KALKD) improves to a C/D class. The upper reaches of the Klein Marico River are seasonal and the reaches below the Klein Maricopoort Dam receive no ecological flow releases. The Groot Marico River System originates on the plateau, south of the town Groot Marico. The upper reaches are dominated by a number of dolomitic eyes and tributaries that cut through the mountains south of Groot Marico. This creates deeply incised gorges that are fairly inaccessible for agricultural development and are therefore relatively un-impacted. The Groot Marico River includes the upper and lower Marico River and the following tributaries in the upper reaches, see Table 6:

Rietspruit (A3RIET-RENOS is in a B Ecological class, the lack of habitat prevents this site from reaching an A Ecological class, situated 10 m from dolomitic eye)

Kaaloog se Loop (A3KAAL-GROOT and A3KAAL-RIETS indicate an A/B Ecological class)

Bokkraal (A3BOKK-BOKKR and A3BOKK-WATER indicate an A/B Ecological class

Ribbokfontein se Loop (A3RIBB-SYFER indicate an E/F Ecological class, this river is seasonal and reflected by the class.)

Draaifontein (B Ecological class in the upper reaches and D/E downstream, this is also mainly flow related)

Van Straatensvlei (B/C Ecological class, some negative impacts from alien vegetation in the wetland areas and diary farming)

Polkadraaispruit (The Ecological classes varies between sites but the overall class in a B/C).

All of the tributaries have been identified as biodiversity special features and have also been included in the targeted river reaches for ensuring that 20% of all types of aquatic ecosystems are conserved. The upper reaches of the Groot Marico River, up and downstream from the town, are in an A class at A3GMAR-KOEDO and at A3GMAR-WONDE. Water abstraction for irrigation reduces the Ecological class to B/C further downstream at A3GMAR-DOORN. The site below Groot Marico Bosveld Dam reflects the importance of ecological flow maintenance. This site (A3GMAR-RIEKE) was in an overall C Ecological class for 2005 and 2007 but good rain in January, February and March 2008 increased the flow sufficiently that a B class was reached during April 2008. The river downstream from the Groot Marico Bosveld Dam only flows seasonally due to water abstraction (site A3GMAR-UITKY in a D class due to lack of flow). Molatedi Dam and the Tswasa weir are the other water abstraction points. Water is exported to Botswana at the Tswasa weir. The sites A3GMAR-TSWAS and A3GMAR-DERDE are both in B classes during good flow conditions and deteriorate to C Ecological classes when flow is reduced. The Ngotwane River is also a tributary of the Groot Marico River and is fed by a dolomitic eye close to the town of Dinokana. The dolomitic eye supplies drinking water to the town, the Ecological class downstream from the eye (A1NGOT-DINOK) varies

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according to flow A/B. Downstream at A1NGOT-PUANE, the reduced flow, urban and rural impacts deteriorates the river to a C class.

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M o l o p o R i v e r S i t e s

Figure 6: Molopo River Sites

134


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Ngotwane

Hex

Mar

i co

Ma re etsane

Sandsl oot

Ma

Mad ibe

M ets em othlaba

Gr o ot -M

a ric o

Lenk

wa n

e

si

St

Let hl akan e

B loubank

R

Skeerpoort

Po lfontein sprui t

Malmanieloop

Lotl hakane

Blo uba nks p

Po lka dra ai sprui t

Gro

o tfon te

i

Bran dv

So ndag

s

Br akfonteinsprui t

Pie

Klip

spru

it

Klein

-Har

ts

A3RIETRENOA3KAALG ROO

A3KAALRIETA3RIBBSYFE

A3DRAADRAA

A3DRAARHEN

A3G MARSALL

A3G MARW O NDA3G MARDO O R

A3G MARRIEK

A3KMAR DOO R

A3MO LEO TTO

A3KMAR KALK

A3G MARSTR A

A3G MARUIT K

A3G MARLO TT

A3G MART SW A

A3G MARDE RD

A1NG OT DINOA1NG OT PUA N

A3VANSR IET

40 0 40 80 Miles


Nw new border.shp

N

EW

S

Marico sites

Figure 7: Marico River Sites

135


Table 5: Summary of Index of Habitat Integrity and SASS5 Ecological class results for Molopo, Marico River and tributaries (2005, 2007, 2008)


Tributary

IHI Instream 2007

IHI Riparian 2007

Survey dates SASS No Taxa


ASPT

D4MOLO-BUHRM Molopo C

C 18/04/2005 83 21 3.95

D4MOLO-MAFIK Molopo D D 18/04/2005 36 11 3.27 20/06/2005 10 5 2

14/09/2005 18 7 2.57 21/11/2005 16 7 2.29 16/03/2007 18 7 2.57 D4MOLO-LOMAN Molopo

F F 18/04/2005 63 16 3.94 20/06/2005 34 10 3.4

14/09/2005 26 9 2.89 21/11/2005 39 11 3.55 30/08/2007 20 6 3.33 D4MOLO-MODIM Molopo C D 18/04/2005 66 16 4.13 20/06/2005 64 15 4.27 14/09/2005 60 14 4.29 16/03/2007 26 8 3.25 A3RIET-RENOS Rietspruit Groot

Marico C C 21/04/2005 145 26 5.58 25/07/2005 96 19 5.05

20/09/2005 172 27 6.37 25/11/2005 200 34 5.88 08/03/2007 189 33 5.73 27/08/2007 191 30 6.37 10/04/2008 162 29 5.59


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3KAAL-GROOT Kaaloog se loop

Groot Marico B B 21/04/2005 129 24 5.38 21/07/2005 88 15 5.87

20/09/2005 201 28 7.18 25/11/2005 262 41 6.39 08/03/2007 249 40 6.23 21/08/2007 246 39 6.31 10/04/2008 294 47 6.26 A3KAAL-RIETS Kaaloog

se loop Groot Marico A A 21/04/2005 186 31 5.64 21/07/2005 147 24 6.13

19/09/2005 279 41 6.8 24/11/2005 245 38 6.45 08/03/2007 277 43 6.44 22/08/2007 204 32 6.38 08/04/2008 267 42 6.36 A3BOKK-BOKKR Bokkraal

se loop Groot Marico

Poplar felling on 08/03/2007

x X x 21/08/2007 208 34 6.12

10/04/2008 213 35 6.09 A3BOKK-WATER Bokkraal

se loop Groot Marico 08/03/2007 255 41 6.22 21/08/2007 264 42 6.29

10/04/2008 264 43 6.14 A3RIBB-SYFER Ribbokfo

ntein se loop

Groot Marico

B B 21/04/2005 83 19 4.37 22/07/2005 66 13 5.08


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3DRAA-DRAAI Draaifontein

Groot Marico B C 22/07/2005 177 30 5.9

22/09/2005 177 33 5.36 No Veg

23/08/2007 91 16 5.69

A3DRAA-RHENO Draaifontein

Groot Marico B C 27/07/2005 169 28 6.04

21/09/2005 201 35 5.74 29/11/2005 236 40 5.9 23/08/2007 161 30 5.37 A3VANS-RIETF Vanstraat

ensvlei Groot Marico B C 22/04/2005 134 27 4.96 22/07/2005 100 23 4.35

28/11/2005 156 33 4.73 05/03/2007 173 32 5.41 24/08/2007 179 31 5.77 A3DRAA-BRONK Draaifont

ein Groot Marico B C 21/04/2005 80 18 4.44 21/07/2005 74 16 4.63

07/03/2007 106 24 4.42 22/08/2007 158 32 4.94

136



Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3GMAR-KOEDO Groot Marico

B C 26/04/2005 260 41 6.34 21/07/2005 173 27 6.41

19/09/2005 285 41 6.95 24/11/2005 224 35 6.4 06/03/2007 299 46 6.5 22/08/2007 261 39 6.69 08/04/2008 242 37 6.54 A3POLK-SWART Polkadraa

ispruit Groot Marico B C 25/04/2005 109 20 5.45 25/07/2005 45 12 3.75

21/09/2005 103 20 5.15 28/11/2005 79 18 4.39 05/03/2007 120 20 6 No veg

24/08/2007 51 13 3.92

A3UNSP-RIETV Tributary of Polkadraaispruit

Groot Marico 25/04/2005 144 26 5.54 22/07/2005 90 15 6

21/09/2005 157 26 6.04 28/11/2005 174 33 5.27 A3POLK-VLEID Polkadraa

ispruit Groot Marico B C 25/04/2005 62 14 4.43 26/07/2005 72 14 5.14

21/09/2005 88 19 4.63 05/03/2007 112 21 5.33 24/08/2007 98 20 4.9 A3UNSP-BOKKR Tributary

of Polkadraaispruit

Groot Marico 25/04/2005 115 22 5.23


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3POLK-DOORD Polkadraaispruit

Groot Marico B B 25/04/2005 79 18 4.39 25/07/2005 44 11 4

21/09/2005 92 22 4.18 29/11/2005 47 14 3.36 A3UITV-STERK Uitvlugsp

ruit Polkadraaispruit

25/04/2005 134 25 5.36 26/07/2005 118 22 5.36

21/09/2005 123 22 5.59 29/11/2005 198 32 6.19 06/03/2007 143 25 5.72 27/08/2007 134 24 5.58 A3POLK-TWYFE Polkadraa

ispruit Groot Marico C D 25/04/2005 131 22 5.92 26/07/2005 120 23 5.22

21/09/2005 114 21 5.43 29/11/2005 203 34 5.97 06/03/2007 151 25 6.04 27/08/2007 166 29 5.72 A3GMAR-VERGE Groot

Marico C C 26/04/2005 196 31 6.32 26/07/2005 180 28 6.43

19/09/2005 256 39 6.56 24/11/2005 245 37 6.62 13/03/2007 243 40 6.08 22/08/2007 247 38 6.5 A3GMAR-SALLI Groot

Marico C C 26/04/2005 141 24 5.88 26/07/2005 166 27 6.15

16/09/2005 280 43 6.51 23/11/2005 222 34 6.53


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3GMAR-WONDE Groot Marico

C C 26/04/2005 208 34 6.12 22/06/2005 249 39 6.38

16/09/2005 247 39 6.33 23/11/2005 310 49 6.33 07/03/2007 279 46 6.07 Fire

23/08/2007 268 43 6.23

08/04/2008 249 40 6.23 A3GMAR-DOORN Groot

Marico C D 26/04/2005 136 23 5.91 22/06/2005 191 32 5.97

16/09/2005 250 38 6.58

ALL WATER DIVERTED BY WEIR on 07/03/2007

x x x No Veg 23/08/2007 160 26 6.15

137


A3GMAR-RIEKE Groot Marico

E E 20/04/2005 115 22 5.63 22/06/2005 124 24 5.17

16/09/2005 145 26 5.58 23/11/2005 151 27 5.59 07/03/2007 115 23 5 27/08/2007 119 22 5.41 07/04/2008 173 31 5.58


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3KMAR-DOORN Klein Marico

Groot Marico

B B Seasonal

A3MOLE-OTTOS Molemaneloop

Klein Marico

B C 16/03/2007 181 34 5.32 20/08/2007 85 18 4.72

A3KARE-GHOLF Kareespruit

Klein Marico D D 27/04/2005 69 17 4.06 27/07/2005 88 21 4.19

22/09/2005 104 23 4.52 02/12/2005 70 19 3.68 A3KARE-RAILW Kareespr

uit Klein Marico D D 27/04/2005 63 15 4.2 26/07/2005 62 16 3.88

22/09/2005 79 20 3.95 02/12/2005 100 21 4.76 15/03/2007 90 19 4.74 A3KARE-ABJAT Kareespr

uit Klein Marico D C 27/04/2005 18 7 2.57 27/07/2005 4 3 1.33

22/09/2005 8 4 2 02/12/2005 20 6 3.33

RAW SEWERAGE on 15/03/2007

x x x

A3KMAR-N4ROA Klein Marico

Groot Marico D C


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A3KMAR-KALKD Klein Marico

Groot Marico E F 27/04/2005 104 24 4.33

15/03/2007 137 25 5.48 29/08/2007 141 29 4.86 A3KMAR-NOOIT Klein

Marico Groot Marico C D 27/04/2005 64 14 4.57

A3GMAR-STRAA Groot Marico

D D

A3GMAR-UITKY Groot Marico

C C 07/04/2008 76 16 4.75

A3GMAR-LOTTE Groot Marico

D D 19/04/2005 21 4 5.25

A3GMAR-TSWAS Groot Marico

E E 19/04/2005 140 32 4.38 21/06/2005 115 26 4.4

22/11/2005 144 29 4.97 12/03/2007 115 25 4.6 09/04/2008 120 26 4.62 A3GMAR-DERDE Groot

Marico

C C 19/04/2005 111 25 4.44 21/06/2005 116 27 4.3

15/09/2005 70 14 5 22/11/2005 136 28 4.86


Tributary

IHI Instream 2007

IHI Riparian 2007



ASPT

A1NGOT-DINOK Ngotwane

Groot Marico 02/12/2005 248 40 6.2 15/03/2007 210 34 6.18

20/08/2007 197 34 5.79 11/04/2008 211 34 6.21 A1NGOT-PUANE Ngotwan

e (Mmaphanyane)

Groot Marico 02/12/2005 84 18 4.67

20/08/2007 83 19 4.37 11/04/2008 117 21 5.57

138


9. Elands River and tributaries The Elands River originates south of the town of Swartruggens in an extensive wetland area and flows in a northerly direction and then north east to the Vaalkop Dam, see Figure 8. The upper reaches of the catchment are dominated by slate mining activities and in a B/C Ecological class, see Table 7. Sediment from some of the slate mines are not sufficiently retained and cause deterioration to a C/D Ecological class at A2UNSP-TRIBU. The upper reaches are steeply sloped while the middle and lower reaches are gentle sloping. Overgrazing in the middle and lower reaches of the catchment contributes to sediment deposition and degradation of the catchment. The Swartruggens Dam and Lindleyspoort Dam supply water for domestic, agricultural and mining activities. The situation below Swartruggens Dam and in Swartruggens (A2ELAN-SWART) is in a D/EF Ecological class. The discharges from the Swartruggens sewerage treatment facilities cause nutrient enrichment at A2ELAN-NOOIT. The area below Lindleyspoort Dam is intensively used for agriculture and no ecological flow releases are made, resulting in a low C/D Ecological class. The Selons River is a highly seasonal tributary in the middle reaches. The Koster River is a tributary of the Selons. The Koster Dam does not release ecological flow. The Ecological class upstream from the dam at A2KOST-NAAUW is in a D/EF class, mainly due to flow and nutrient enrichment problems. The Dwarsspruit is an important tributary of the Selons from a fish diversity perspective. The Ecological classes of the Dwarsspruit are B/ high C. The Laregane River is a tributary of the lower Elands; this river originates from mining areas and is in a C Ecological class at A2LARE-HARTB. The lower Elands consist mainly of deep sandy pools with very little flow. The water quality has also deteriorated as a result of erosion and high sediment loads occur in the river’s middle to lower reaches. Sesbania have infested large parts of the river and the resulting deposition of seeds in the Vaalkop Dam basin could potentially create problems.

139


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Crocodile

Hex

Elands

Tolwane

B oful

e

kei

Kolob

eng

Ko ste r

Groo t-M

a r ico

Lera

gane

Mankwe

Bier

s pru

it

Moretele

Lepenya

Bloubank

Dwarsspruit

uit

Blouban kspruMonyagole

aselaje

Tooy

spru

it

Droekloofspru it

Brak

kl oof

sprui

tBrandvle

Modderfon te i

Brakspru

it

Sa n ds p ru it

Pienaars

Sand

Kareesp

r uit

Koedoespruit

Selons

Klipvoor

Vaalkop

Hartbeespoort

Roodekopjes

Bospoort

-Bosveld

Olifantsnek

Bierspruit

Buffelspoort

Lindleys Poort

A3POLKSWAR

A2ELANVLAKA2UNSPTRIBA2ELANDOOR

A2ELANKLIP

A2ELANSWAR

A2ELANNOOI

A2ELANLIND A2ELANBESTA2ELANHOOG

A2ELANRHENA2ELANBUFF

A2LAREHART

A2ELANRIETA2ELANBULH

A2SELODOOR

A2KOSTNAAU

A2SUIGSTEE

A2KOSTTWEEA2DWARBULH

A2DWARWATE

A2SELOSTRO

A2KOLORHEN

A2BOFUVARK

30 0 30 60 Miles


Nw new border.shp

N

EW

S

Elands sites

Figure 8: Elands River Sites

140


Table 6: Summary of Index of Habitat Integrity and SASS5 Ecological class results for Elands River and tributaries (Western Crocodile)



IHI Riparian 2007

Survey dates

SASS No Taxa

ASPT Survey dates

SASS No Taxa

ASPT

A2ELAN-VLAKF

Elands Crocodile C C 26/06/2006 137 26 5.15

A2UNSP-TRIBU

Tributary of Elands

Elands

26/06/2006 102 19 5.37

Bridge construction 29/11/2006

x x x

17/07/2008 141 23.00 6.13 A2ELAN-DOORN

Elands Crocodile C D 26/06/2006 186 33 5.64 29/11/20

06 171 32 5.34

17/07/2008 121 20.00 6.25

A2ELAN-KLIPB Elands Crocodile C C 26/06/2006 142 26 5.46 29/11/2006 168 30 5.6

18/07/2008 179 33.00 5.42 A2ELAN-DOORK

Elands Crocodile C C 30/06/2006 141 22 6.41 30/11/20

06 205 36 5.69

18/07/2008 179 33.00 5.42 A2ELAN-SWART

Elands Crocodile D E 28/06/2006 73 13 5.62 30/11/2006 84 22 3.82

A2ELAN-NOOIT

Elands Crocodile C D 28/06/2006 112 23 4.87 30/11/2006 90 22 4.09

18/07/2008 50 13.00 3.85

A2ELAN-LINDL Elands Crocodile D E 28/06/2006 85 19 4.47



IHI Riparian 2007

Survey dates

SASS No Taxa

ASPT Survey dates

SASS No Taxa

ASPT

A2ELAN-BESTE Elands Crocodile C D 28/11/2006 111 25 4.44

16/07/2008 118 26.00 4.54 A2ELAN-HOOGE

Elands Crocodile C C 29/06/2006 102 21 4.86

16/07/2008 71 16.00 4.44 A2ELAN-RHENO

Elands Crocodile C C

A2ELAN-BUFFE Elands Crocodile B C

A2LARE-HARTB Laregane Elands 29/06/2006 111 23 4.83 27/11/2006 105 23 4.57

A2ELAN-RIETS Elands Crocodile C C 29/06/2006 117 25 4.68 A2ELAN-BULHO

Elands Crocodile D D

A2SELO-DOORN

Selons Elands

A2KOST-NAAUW

Koster Selons 27/06/2006 75 15 5 29/11/2006 70 16 4.38

17/07/2008 81 20.00 4.2



IHI Riparian 2007

Survey dates

SASS No Taxa

ASPT Survey dates

SASS No Taxa

ASPT

A2SUIG-STEEN Suigsloot Koster 29/11/2006 148 30 4.93

A2KOST-TWEER

Koster Selons

A2DWAR-BULHO

Dwarsspruit

Selons 27/06/2006 142 24 5.92 28/11/20

06 139 30 4.63

16/07/2008 131 25.00 5.24

A2DWAR-WATER

Dwarsspruit

Selons

27/06/2006 111 22 5.05

Total removal of riverine vegetation 30/11/20

x x x

141


06

A2SELO-STROO Selons Elands A2KOLO-RHENO

Kolobeng Bofule or Bierspruit

A2BOFU-VARKE

Bofule or Bierspruit

Crocodile

10. Hex and Sterkstroom Rivers The Hex River originates south of the Rustenburg complex and flows north to the Vaalkop Dam, see Figure 9. The Olifantsnek Dam is situated in the upper reaches of the Hex River. The confluence of the Hex and Klein Hex is in the Olifantsnek Dam. The upper reaches of the Hex River is in a B/ high C Ecological class (A2HEX-BUFFE, A2HEX-LEEUW and A2HEX-OLIFA), the main impacts result from water abstraction and farming activities. The Waterkloofspruit originates in the Kgwasane Mountain Reserve from an important mountain catchment wetland system. The biomonitoring site (A2WATE-WATER) is located close to Rustenburg and indicate a high B Ecological class, see Table 8. Below Rustenburg heavy infestations of alien vegetation, flow modifications, urban runoff and mining are the major impacts on the river. The area upstream from Bospoort Dam at A2HEX-PAARD is in an E/F Ecological class, below the dam at A2HEX-ROOIW in a D/ low C. This river is degraded and contributes to water quality problems in Vaalkop Dam. The Sterkstroom is a tributary of the Crocodile River that has its origin in the Magaliesberg. The upper reaches result in A/B Ecological classes (A2STER-RIETF, A2STER-KROMR and A2UNSP-KROMR). The upper reaches must be conserved and an Index of Habitat Integrity should be done. The agricultural activities in the vicinity of Buffelspoort Dam reduce the Ecological class to a C (A2STER-BUFFE). The combination of reduced flow and mining impacts downstream from Buffelspoort Dam result in Ecological classes of D (A2STER-WAAIK) and E/F (A2STER-ZWART). The water quality that enters the Roodekopjes Dam is thus not of a good quality.

142


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Ha rtbe espoo rt

Ro ode ko pje s

Bospoo rt

Olifa ntsne k Buffelspo ort

Hex

Cro cod ile

Sterk s troom

Ma re tlw an a

Gwathle

Tsh u

k uts

we

R ooik lo ofs

p ru it

Wa terkloo fsp ru it

Sterkstroom

E lands

Sands pru it

A2E LA NBUL H

A2HE X BUFFE

A2HE X LEE UW

A2HE X OLIFA

A2K LE IMIDD

A2W A TEW ATE

A2HE X W A TER A2K LIP W A TE

A2HE X RUSTEA2K LIP PAA R

A2HE X PAA RD A2HE X REINK

A2HE X ROO IW

A2S TERRIE TA2S TERK ROM

A2S TERB UFF

A2S TERS PRU

A2S TERZW A R

A2S TERMA MO

A2S TERW A AI

20 0 20 40 Mil


Nw new border.shpN

EW

S

Hex and Sterkstroom sites

Figure 9: Hex and Sterkstroom River Sites

143


Table 7: Summary of Index of Habitat Integrity and SASS5 Ecological class results for Hex and Sterkstroom Rivers (Middle Croc)



IHI Riparian 2007

Survey dates

SASS No Taxa

ASPT Survey dates

SASSNo Taxa

ASPT

A2HEX-BUFFE Hex Elands B C 07/09/2006 111 20 5.55 09/06/2008 164 26 6.31

A2HEX-LEEUW Hex Elands B C 09/06/2008 164 26 6.31

A2HEX-OLIFA Hex Elands C C 07/09/2006 151 28 5.39 09/06/2008 126 23 5.48

A2KLEI-MIDDE Rooikloofspruit

Hex C C

A2WATE-WATER Waterkloofspruit

Hex 07/09/2006 170 27 6.3

A2HEX-WATER Hex Elands C D

A2KLIP-WATER Klipgatspruit?

Hex

A2HEX-RUSTE Hex Elands D D

A2KLIP-PAARD Klipgatspruit?

Hex

A2HEX-PAARD Hex Elands C C 08/09/2006 45 11 4.09



IHI Riparian 2007

Survey dates

SASS No Taxa

ASPT Survey dates

SASSNo Taxa

ASPT

A2HEX-REINK Hex Elands F F

A2HEX-ROOIW Hex Elands D F 23/08/2006 66 15 4.4 11/06/2008 92 20 4.6

A2STER-RIETF Sterkstroom Crocodile 21/08/2006 205 33 6.21 10/06/2008 130 21 6.19

A2STER-KROMR Sterkstroom Crocodile 21/08/2006 153 24 6.38

A2UNSP-KROMR Tributary of Sterkstroom

Sterkstroom 21/08/2006 98 17 5.76 10/06/2008 142 22 6.45

A2STER-BUFFE Sterkstroom Crocodile 21/08/2006 110 19 5.79 10/06/2008 116 20 5.8

A2STER-SPRUI Sterkstroom Crocodile 22/08/2006 70 14 5 10/06/2008 70 13 5.38

A2STER-ZWART Sterkstroom Crocodile 10/06/2008 43 10 4.3

A2STER-MAMOG Sterkstroom (Gwathle)

Crocodile 22/08/20

06 59 14 4.21

A2STER-WAAIK Sterkstroom (Gwathle)

Crocodile 22/08/2006 76 17 4.47

11. Crocodile River and tributaries The Crocodile River originates in Gauteng in Johannesburg and flows in a northerly direction through Hartbeespoort Dam and then north westwards, supplying water to agricultural and mining activities in the North West Province, see Figure 10. The Crocodile River and tributaries are in a D/EF Ecological class (see Table 9) with the exceptions of:

The Ramogatla tributary at A2RAMO-KLIPK, this site was in a B class (September 2006) and has since deteriorated to a C (December 2006) and D (May 2008).

The Tolwane at A2TOLW-NOOIT, this site was in a C class (September 2006) and has deteriorated to an E/F (December 2006 and May 2008).

The Pienaars downstream from Klipvoor Dam at A2PIEN-BUFFE, this site was in a high C (September 2006), B (December 2006) and high C (May 2008).

144


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Klipvoor

Vaalkop

Hartbeespoort

Roodekopjes

Bospoort

Olifantsnek Buffelspoort

Hex

Ap ie s

Crocodile

Pienaars

Plat

Tolwane

Kutsw ane

Tshwane

Sand

Motlhabe Moretele

Karees

pruit

Rosespruit

Magal ies

Boekenhoutspruit

Swartspruit

Matshikit i

Lepenya

Ramogatla

Mar

ier ie

t sa

Madi ba m

atsh o

Elands

Pienaars

A2DEKRDEKR

A2CROCBRIT

A2ROSEMAMOA2CROCZOUT

A2KAREHART

A2KAREZOUT

A2RAMOKLIP

A2CROCVAAL

A2UNSPOUDE

A2SANDNOOIA2TOLWNOOI

A2TRIBKLIPA2TOLWKLIP

A2TOLWPALM

A2PIENIFR4A2UNSPKLIP

A2PIENIFR2A2BLOKDEMO

A2PIENBUFF

30 0 30 60 Miles


Nw new border.shpN

EW

S

Crocodile sites

Figure 10: Crocodile River Sites

145


Table 8: Summary of Index of Habitat Integrity and SASS5 Ecological class results for Crocodile River and tributaries (Croc East)

RHP Site Code River Name Tributary IHI Instream 2007 IHI Riparian 2007 Survey dates SASS No Taxa ASPT Survey dates SASS No Taxa ASPT

A2DEKR-DEKRO De Kroon Spruit Crocodile D D

A2CROC-BRITS Crocodile E D

A2ROSE-MAMOG Rosespruit Crocodile 11/12/2006 75 17.00 4.41 15/05/2008 36 7.00 5.14

A2CROC-ZOUTP Crocodile C D 04/09/2006 79 18.00 4.39 11/12/2006 67 15.00 4.47

A2KARE-HARTB Kareespruit Crocodile 12/05/2008 34 9.00 3.78

A2KARE-ZOUTP Kareespruit Crocodile 04/09/2006 69 15.00 4.6

A2RAMO-KLIPK Ramogatla Crocodile 04/09/2006 138 27.00 5.11 11/12/2006 102 20.00 5.1 12/05/2008 72 15.00 4.8


A2CROC-VAALK Crocodile C D 06/09/2006 31 9.00 3.44 12/12/2006 77 19.00 4.05

15/05/2008 102 23.00 4.43

A2UNSP-OUDEK Tributary of Sand Sand

A2SAND-NOOIT Sand Tolwane

05/09/2006 67 16.00 4.19 No work, serious safety concerns 13/12/2006

x x x

A2TOLW-NOOIT Tolwane Pienaars (Moretele) 05/09/2006 118 24.00 4.92 13/12/2006 65 17.00 3.82

14/05/2008 66 13.00 5.08

A2TRIB-KLIPG Tributary of Tolwane Tolwane

A2TOLW-KLIPG Tolwane Pienaars (Moretele)

A2TOLW-PALMI Tolwane Pienaars (Moretele) 13/05/2008 87 16.00 5.44

A2PIEN-IFR4 Pienaars (Moretele) Crocodile

146




A2UNSP-KLIPV Tributary of Pienaars (Moretele) Pienaars (Moretele)

A2PIEN-IFR2 Pienaars (Moretele) Crocodile 06/09/2006 51 11.00 4.64 12/12/2006 59 15.00 3.93

A2BLOK-DEMON Blokspruit Pienaars (Moretele)

A2PIEN-BUFFE Pienaars (Moretele) Crocodile 06/09/2006 120 22.00 5.45 12/12/2006 181 32.00 5.66

13/05/2008 120 22.00 5.45

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12. Conclusion Most of the river systems in the Province have been impacted by human activities and therefore the habitat integrity has deteriorated. Most rivers can be considered to be in a moderately to largely modified state (category C to D). Integrity of a largely natural state (category A) is rarely found in the assessed rivers. Improved management and rehabilitation actions are required in the modified rivers to attempt improvements and to prevent further degradation. Conservation actions are required for the largely natural rivers as they support unique biodiversity features and subsequent ecological goods and services. The continued monitoring and reporting of the status of the aquatic ecosystem in the province is essential in this water scarce area. Challenges

Availability and appointment of experts to do biomonitoring of fish. Availability and appointment of support staff to assist with the aquatic

invertebrates, habitat integrity, and riparian vegetation monitoring. Low/no flow of rivers in dry seasons and high flow in wet seasons, causing a

discontinuation in the planned monitoring programme. Application of biomonitoring indices can only be done by experts. Server access problems prevented the direct capture to the National Rivers

Database, problem solved in June 2008. Kilometre restrictions during 2007, 2008, 2009. Lack of strong enforcement to prevent further degradation of river systems

Opportunities

Informed decisions, based on scientific data, can be made on issues related to river- and catchment management.

A reliable database is being developed to support State of Environment reporting in the province.

Biomonitoring training provided to staff members and other partners (Universities and DWAF staff).

To develop and implement a biomonitoring programme that will support integrated water resource management

The integration of freshwater and terrestrial conservation planning 13. References BARBER-JAMES HM (2001) Freshwater Biomonitoring Using Benthic Macroinvertebrates. Short

course on biomonitoring. Grahamstown. CHUTTER FM (1998) Research on the Rapid Biological Assessment of Water Quality Impacts in

Streams and Rivers. WRC Report No 422/1/98. Water Research Commission. Pretoria.

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DAVIES B and DAY J (1998) Vanishing Waters. University of Cape Town Press.

University of Cape Town. Rondebosch. 487pp. DICKENS CWS and GRAHAM M (2002) The South African Scoring System (SASS)

Version 5 rapid bio-assessment method for rivers. African Journal of Aquatic Science 27 1-10.

EEKHOUT S, BROWN, CA and KING, JM (1996) National Biomonitoring Programme for

Riverine Ecosystems: Technical Considerations and Protocol for the Selection of Reference and Monitoring Sites. NBP Report Series No.3. Institute for Water Quality Studies, Department of Water Affairs and Forestry, Pretoria.

IVERSEN TM, MADSEN BL and BǾGESTRAND J (2000) River conservation in the

European Community, including Scandinavia. In: Boon PJ, Davies BR and Petts GE (eds) Global Perspectives on River Conservation: Science Policy and Practise. John Wiley and Sons Ltd.

KLEYNHANS CJ (1999) The development of a fish index to assess the biological

integrity of South African rivers. Water SA 25 (3) 265-270. ROUX DJ (2001) Biomonitoring of Rivers. CSIR Environmentek. Short course on

biomonitoring. Grahamstown. WALMSLEY RD (2000) Perspectives on Eutrophication of Surface Waters: Policy/Research Needs

in South Africa. Report No KV129/00. Water Research Commission. Pretoria.

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MAIN ISSUES/CONCERNS RAISED & RESOLUTIONS TAKEN AT THE CONFERENCE

Main Issues & Concerns Raised

1. There is a lack of capacity at DEAT and DWAF and in provincial conservation departments. Also a steady loss of skilled and experienced staff.

2. Authorities do not implement the environmental laws. 3. Poor management of water resources by local authorities and municipalities. 4. Pollution of our water resource is a huge and growing problem and a major

threat to all water users. 5. There is a lack of good environmental education strategies. 6. DME and mining companies do not follow due legal process. For example

permits issued without stakeholder consultation. 7. There is a lack of compliance by developers. The term ‘sustainability’ needs to be

defined. 8. Problem of illegal fishing increasing. Poachers resort to arms when confronted by

authorities at dams like Inanda. 9. If implemented correctly a national fishing licence could result in significant

funding for conservation of our freshwater fish resource. Resolutions taken

1. There should be pro-active liaison with DWAF. To be discussed by YWG Exco. 2. Further research should be undertaken on the genetics of yellowfish and the

immediate focus should remain on Labeobarbus natalensis. 3. There should be increased focus on environmental education. 4. For effective management of fish in the provinces there should be a single fishing

licence which distinguishes between subsistence and sport fishing. 5. The 2010 conference to be held at the Willem Pretorius Reserve outside

Winburg.

PROCEEDINGS OF THE 13TH CONFERENCE · 2009-06-10 · 4 13th Yellowfish Working Group Conference...

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