circabc.europa.eu · Web viewThis Risk Assessment refers to genus Ameiurus and includes information...

EU NON-NATIVE SPECIES RISK ANALYSIS – RISK ASSESSMENT TEMPLATE V1.0

1

EU NON-NATIVE ORGANISM RISK ASSESSMENT SCHEME

Name of genus: Ameiurus Rafinesque, 1820 – bullheads Ameiurus brunneus Jordan, 1877 – snail bullhead Ameiurus catus (Linnaeus, 1758) – white catfish, white bullhead Ameiurus melas (Rafinesque, 1820) – black bullhead, Ameiurus natalis (Lesueur, 1819) – yellow bullhead, Ameiurus nebulosus (Lesueur, 1819) – brown bullhead, Ameiurus platycephalus (Girard, 1859) – flat bullhead Ameiurus serracanthus (Yerger and Relyea, 1968) – spotted bullheadRetrieved [November, 11, 2016] from the Integrated Taxonomic Information System on-line database, http://www.itis.gov.

Author: Deputy Direction of Nature (Spanish Ministry of Agriculture and Fisheries, Food and Environment)Risk Assessment Area: EuropeDraft: 20 of DecemberFinal version: 31/01/2016

Peer reviewed by: Emili García-Berthou, Professor of Ecology. University of Girona. Institut of Aquatic Ecology. 17003 Girona, Catalonia, Spain. Tel.: +34 972 41 8369. http://www.udg.edu/greco; Personal web page: http://www.invasiber.org/GarciaBerthou/; https://twitter.com/garciaberthou

Peer reviewed by: Felipe Morcillo Alonso. Associate Professor. Ecology Department. Complutense of Madrid University. email: [email protected]; www.felipemorcillo.comDate of finalisation: 22/01/2017

Date of finalisation: 23/01/2016

mailto:[email protected]

https://twitter.com/garciaberthou

http://www.invasiber.org/GarciaBerthou/

http://www.udg.edu/greco

http://www.itis.gov/


This Risk Assessment refers to genus Ameiurus and includes information about the most representative species, which have been introduced in Europe and established populations in at least one country. The characteristics of these species are representative for the genus Ameiurus.

2


EU CHAPPEAU

QUESTION RESPONSE

1. In how many EU member states has these species been recorded? List them.

Ameiurus melas (Black bullhead):Austria, Germany (Wiesner et al, 2010), Bulgaria (Uzunova y Zlatanova, 2007), Poland (Nowak, 2010), Belgium, France, Italy, The Netherlands, UK (Holčík, 1991; Rutkayová et al., 2013), Portugal (Ribeiro et al, 2006), Spain (Elvira, 1984), Croatia (Jelić et al, 2010), Slovenia (Piria et al, 2016), Czech Republic (Hartvich and Lusk, 2006), Romania (Wilhelm 1998; Gaviloaie and Falka 2006), Hungary (Bódis et al, 2012), Slovakia (Koščo et al., 2004; Rutkayová et al., 2013), Denmark, Finland (Secretariat of NOBANIS, 2012), Ireland (Minchin, 2007; CABI, 2015a) and possible Greece (Barbieri, 2015).Ameiurus nebulosus (Brown bullhead):Belgium, Bulgaria, Netherlands, UK (Olenin et al., 2008); Austria, Poland, Portugal, Spain, Italy, France, Germany, Czech Republic (Froese and Pauly, 2016); Croatia, Slovenia (Piria et al, 2016); Estonia, Ireland, Slovakia, Sweden (Secretariat of NOBANIS, 2012); Bulgaria, Finland, Romania (Global Invasive Species, 2016); Luxembourg (Ries et al, 2014); Greece (Barbieri, 2015); Denmark, Hungary, Ireland, UK (CABI, 2015b; Rutkayová,et al.,2013) Ameiurus natalis (Yellow bullhead):There are a number of reports of its introduction into Italy (Welcomme, 1988; Hol-cík, 1991; Froese and Pauly, 2016). However, there is no reliable evidence for this. (CABI, 2009).

Ameiurus catus (White catfish)UK (Britton and Davies, 2006; Zieba, 2010), Poland (Nowak et al. 2008, 2010)

There is no information about the introduction of any of the other three species of Ameiurus in Europe.

3


2. In how many EU member states has this species currently established populations? List them.

The unclear taxonomic status of both A. melas and A. nebulosus resulted in more doubts about the occurrence of these species in some countries (Rutkayová et al., 2013).

Related to Central and North Europe countries and according to Secretariat of NOBANIS (2012), Ameiurus melas and Ameirus nebulosos are classified in the Category 2 “Species with no detailed distribution map available. Species are established in the NOBANIS region either recently or has been for a longer period of time but are still expanding their introduced range. Risk profiles of category 2 species will be useful for countries to create their alarm list“.

Ameiurus melas The black bullhead (Ameiurus melas) is known to have been introduced to most of the European countries as pointed-out in the first question, but established self-sustaining populations have been confirmed for: Belgium, The Netherlands (Verreycken et al. 2010), Austria (Wiesner et al. 2010), Germany (Wolter and Röhr, 2010), Czech Republic (Musil et al., 2008), UK (Wheeler, 1979; Copp et al, 2016), France (Copp, 1989; Cucherousset et al., 2006 ), Hungary (Bódis et al. 2012), Italy (Pedicillo et al. 2009), Poland (Nowak et al. 2010a, Nowak et al. , 2010b; Grabowska, 2010), Portugal (Gante and Santos 2002; Ribeiro et al. 2006), Romania (Wilhelm, 1998; Gaviloaie and Falka), Slovakia (Koščo et al., 2010), Croatia (Ćaleta et al., 2011), Slovenia (Piria et al, 2016), Spain (Miranda et al., 2010, De Miguel et al., 2014); Finland (Secretariat of NOBANIS, 2012), Ireland (Welcomme, 1988).A total of 18 countries of the 28 Member states. Ameiurus nebulosus: Kottelat and Freyhof (2007) indicated that it is established in Germany, Italy and Finland. Although (CABI, 2015b) mention that it is established in many European countries, A. nebulosus has often been mistaken for A. melas (See Rutkayová et al., 2013)

The distribution of A. melas has been described quite well. Its occurrence was confirmed in a large part of Europe, e.g. In Germany, the Czech Republic, Poland, Slovakia, Hungary, Romania. Concerning the populations of A. nebulosus, the situation is different. They have been recorded rather incoherently and mainly in central and eastern parts of Europe (up to Kuban and Volga drainages). Taking into

4

http://www.cabi.org/isc/datasheet/94466#19891417812



account these facts, it can be assumed, that the real distribution of both species is possibly wider (Kottelat and Freyhof, 2007).

Taking into account the paragraphs above, we found references of establishment in the following countries. According to Savini et al. (2010) he fish has established feral populations in 19 European countries according to. We found references of this establishment for the next countries: Belgium (Verreycken et al, 2010), Bulgaria (Uzunova and Zlatanova, 2007), Finland (Food Agriculture Organization of the United Nations, 1997), Germany (Scott and Crossman, 1973), Hungary (Food Agriculture Organization of the United Nations, 1997), Italy (Amori et al., 1993), Poland (Food Agriculture Organization of the United Nations, 1997) ; Austria, Czech Republic, Denmark, France, Ireland, Netherlands, Romania, Slovakia (Global Invasive Species Database, 2016), Spain, Portugal (Kottelat and Freyhof, 2007), Greece (Barbieri, 2015). Elvira (2001) also points out Slovenia.

In the UK, there are some species that have been mentioned in one or more literature sources, but scrutiny of the evidence has either refuted, or raised sufficient doubt, that they were ever introduced in the UK (i.e. brown bullhead Ameiurus nebulosus (Britton et a.l, 2010).

Ameiurus natalis was reported as established in Italy (Elvira, 2001). This fact was confirmed only ten years after Gandolfi et al. (1991) had reported there were occurrences of the Yellow catfish in Italy. However, it does not seem to be established in Europe.

Ameiurus catus: There is no information available about the establishment of this species in UK and Poland (where it certainly has been introduced) or in other countries in Europe.

3. In how many EU member states has this species shown signs of invasiveness? List them.

Ameiurus melas:Most of the European countries recognize the evidence of invasiveness in their waters, for instance: France, Poland, Spain, Portugal, Germany, Hungary, Slovakia, Czech Republic, Italy, Romania, Croatia and Slovenia.

Giving the characteristics of this species as described in Invasive Species

5

http://issg.org/database/species/distribution_display.asp?si=612&ri=18263&pc=*&sts=sss&status=Alien&lang=EN#Alien

















Compendium of the Centre for Agriculture and Biosciences International (CABI) –(abundant in its native range; capable of securing and ingesting a wide range of food; gregarious; broad native range; high reproductive potential; longevity (4-5 years); highly adaptable to different environments; invasive in and outside its native range; a habitat generalist; tolerant of shade and poor quality waters) , this species can be considered invasive for all the countries where it has established populations.

As mentioned before, those countries are: Belgium, The Netherlands (Verreycken et al. 2010), Austria (Wiesner et al. 2010), Germany (Wolter and Röhr 2010), Czech Republic (Musil et al. 2008), UK (Wheeler, 1979; Copp et al, 2016), France (Copp, 1989; Cucherousset et al., 2006 ), Hungary (Bódis et al. 2012), Italy (Pedicillo et al. 2009), Poland (Nowak et al. 2010a, Nowak et al. , 2010b; Grabowska, 2010), Portugal (Gante and Santos 2002; Ribeiro et al. 2006), Romania (Wilhelm, 1998; Gaviloaie and Falka), Slovakia (Koščo et al., 2010), Croatia (Ćaleta et al., 2011), Slovenia (Piria et al, 2016), Spain (Miranda et al., 2010, De Miguel et al., 2014); Finland (Secretariat of NOBANIS, 2012), and Ireland (Welcomme, 1988).

Novomeská et al. (2013), for example, studied A. melas from four European countries and consider it a species with “high invasive potential” due to characteristics such as “high reproductive potential, parental care, omnivory, aggressive behaviour and considerable tolerance to water pollution, turbidity, low oxygen concentration, elevated temperatures and a range of pH values”.

The black bullhead has been ranked in several European countries/regions as representing a high risk of being invasive, including Belgium, Iberia and the UK but medium risk in Finland. This invasiveness is demonstrated in some countries, e.g. France where it is among the few freshwater fish listed with a legal status of ‘invasive’. Whereas in the UK, only one of a few reported populations has been confirmed though the species has nonetheless been the subject of regulation since the 1980 (Copp et al., 2016). Related to UK, Ruiz-Navarro et al. (2015) conclude that there was little evidence to suggest that the inability of A. melas to be invasive in the UK was related to insufficient summer temperatures for their reproduction, with their integration into the food web at a relatively high trophic level suggesting that they also have access to ample food resources to facilitate their persistence.

6



Thus, the continuation of their lag phase in the UK appears more related to their lack of dispersal opportunities from this single population in the wild than through ecological constraints. Correspondingly, should individuals from this population disperse in the future, then invasive populations might subsequently develop.

Ameiurus nebulosus:

According to NOBANIS, this species is recognized as invasive (including here that countries where it is considered potentially invasive) in at least 6 countries.

Source: https://www.nobanis.org/species-info/?taxaId=8496

Conversely, according to Savini et al. (2010), the fish has established feral populations in 19 European countries.

Kottelat and Freyhof (2007) indicated that it is established in Germany, Italy and Finland. Although CABI (2009) mentions that it is established in many European countries, A. nebulosus has often been mistaken for A. melas (See Rutkayová et al., 2012). The unclear taxonomic status of both A. melas and A. nebulosus resulted in more doubts about the occurrence of these species in some countries (Rutkayová et al., 2013).

7


Having all these possible mistakes in mind, we found references of establishment for the next 18 countries:Belgium (Verreycken et al., 2010), Bulgaria (Uzunova and Zlatanova, 2007), Finland (Food Agriculture Organization of the United Nations, 1997), Germany (Scott and Crossman, 1973), Hungary (Food Agriculture Organization of the United Nations, 1997), Italy (Amori et al., 1993), Poland (Food Agriculture Organization of the United Nations, 1997), Austria, Czech Republic, Denmark, France, Ireland, Netherlands, Romania, Slovakia, (GLOBAL INVASIVE SPECIES DATABASE, 2016); Spain, Portugal (Kottelat and Freyhof, 2007); Greece (Barbieri, 2015).

Giving the characteristics of this species (abundant in its native range; capable of securing and ingesting a wide range of food; fast growing; broad native range; high genetic variability; high reproductive potential; highly adaptable to different environments; highly mobile locally; a habitat generalist; pioneering in disturbed areas; invasive outside its native range as described in http://www.cabi.org/isc/) it can be considered invasive for all the countries where it has established populations.

There is no information about A. catus and A. natalis as invasive species in Europe, so it is possible that we are in time to prevent the invasion of the rest of the Ameiurus species.

4. In which EU Biogeographic areas could this species establish? Ameiurus melas is established in Continental, Atlantic, Mediterranean and Boreal zones. It is casual in the Arctic zone. Once introduced, the dispersal rate of the species in the Central and North European countries was medium all these areas was medium. (Secretariat of NOBANIS, 2012).

Ameiurus nebulosus is established in Alpine, Continental, Atlantic and Boreal zones. Once introduced, the dispersal rate the Central and North European countries was medium of the species in all these areas was medium. (Secretariat of NOBANIS, 2012).

Ameiurus natalis was reported as established populations in Italy (Elvira, 2001). This fact was confirmed only ten years after Gandolfi et al. (1991) had reported there were occurrences of the Yellow catfish in Italy. However, it does not seem to be currently established in Europe.

8

http://www.cabi.org/isc/


















Ameiurus catus is present in Atlantic and continental regions.

It is to expect that the rest of the species of Ameiurus have the capacity to establish in the same biogeographic areas.

5. In how many EU Member States could this species establish in the future [given current climate] (including those where it is already established)? List them.

Ameiurus melas:The species is already established in Bulgaria, Finland, Germany, Hungary, Italy, Poland, UK, Austria, Czech Republic, Denmark, France, Ireland, Netherlands, Romania, Slovakia, Spain; Portugal, and possible in Greece (where A. nebulosus was confirmed as established; Barbieri, 2015 recognizes that “identification errors between A. nebulosus and the closely related A. melas are possible”)

This species could establish in Luxembourg as a result of a natural spread process (Copp et al, 2016). In Sweden could also establish as a result of natural spread as it is already established in Finland. In Letonia, Estonia and Lithuania there are fewer possibilities to establish because it is not recorded in those countries and because of the boreal climate, but once introduced and due to climate warming, this is not impossible. There is no information about the existence of this species in Malta and Cyprus and it is not confirmed as established in Greece but probably the species of the genus Ameiurus would adapt to the climatic condition in these countries as the clime is alike to the zones where the species is established already.

The study developed by the Secretariat of NOBANIS in 2012 found that A. melas did not establish population in Latvia, Lithuania or Estonia (countries with boreal climate) but A. nebulosus (with very similar requirements) was recorded in Estonia.

Ameiurus nebulosus:The species is established in at least 18 countries: Finland (Food Agriculture Organization of the United Nations, 1997), Bulgaria, Austria, Ireland, Poland, Portugal, Spain, Italy, France, Germany, Czech Republic (Froese et al., 2016); Ireland, Finland (Secretariat of NOBANIS, 2012); Hungary, Romania (Global Invasive Species Database, 2016); Greece (Barbieri, 2015).

In conclusion A. nebulosus could establish anywhere in Europe, where it seems not to be established yet: Malta, Cyprus, Croatia, Slovenia, Luxembourg, Latvia, Lithuania, Estonia, Sweden (similar climate to other countries where it is already

9












established or because it is closed and easy to spread). A recently established population was located in 2012 in Lake Kerkini, probably introduced from Bulgaria (Barbieri, 2015).

Ameiurus natalis was reported as with established populations in Italy (Elvira, 2001). This fact was confirmed only ten years after Gandolfi et al. (1991) had reported there were occurrences of the Yellow catfish in Italy. However, it does not seem to be currently established in Europe; there is no information about his presence in other EU countries. This species could establish anywhere, at least in Mediterranean zone.

Ameiurus catus seems not to be established yet, but it´s presence was recently confirmed in Poland (Nowak, 2008) and UK (Britton, 2006).

It seems that not only A. melas and A. nebulosus are able to establish self-sustaining populations in Europe. Further establishment in Great Britain of A. nebulosus may be hindered by the temperate climate. This would inhibit reproduction, as it requires temperatures >21° C (Kazyak and Raesby, 2003).

The North American catfish Ameiurus catus was recorded as introduced to Europe for the first time in Great Britain. An albino variety of 620 mm fork length and 4550 g was believed to have been an ornamental fish that was introduced subsequently into the wild (Britton and Davies, 2016).

We consider that the characteristics of the genus Ameiurus makes all the species desirable candidates to establish in Europe, once introduced.

In the aquatic ecosystems the influence of zonal factors such as variations in temperature and precipitation is not very relevant, so that it is possible to speak of a remarkable homogeneity of the aquatic environment throughout the world. This fact supports the idea that Ameiurus spp. could establish anywhere is introduced.

6. In how many EU member states could this species become invasive in the future [given current climate] (where it is not already established)?

Ameiurus melas:Using an invasiveness screening tool for freshwater fishes, FISK (Copp et al. 2009), the black bullhead has been ranked in several European countries/regions as

10

http://link.springer.com/article/10.1007/s11160-016-9436-z#CR24


representing a high risk of being invasive, including Belgium, Spain, Portugal and the UK (Verbrugge et al., 2012; Almeida Real et al., 2013; Simonović et al., 2013; Tarkan et al., 2014; Piria et al. 2016), but medium risk in Finland (Puntila et al. 2013).

The species could become invasive in many of Europe’s rivers, if established. The confidence of this prediction is higher in freshwater habitats, from small farm ponds to large lakes, creeks and rivers. They prefer soft bottoms, avoiding free flowing waters where water moves rapidly. They can tolerate poorly oxygenated, polluted, turbid, and high temperature waters.According to DAISIE, A. melas is declared as invasive in Belgium, Czech Republic, UK, Germany and Italy, but established populations in 19 European countries. Summarizing it may establish in the hole 28 EU Member states.

Ameiurus nebulosus:According to NOBANIS, Ameiurus nebulosus is considered invasive in 6 countries included in NOBANIS Network (See question 3, above) but see above about taxonomic uncertainty.

In Scandinavian countries (Finland, Sweden) it seems that this species demonstrated a lower risk of becoming invasive than in countries of intermediate or lower latitudes. The same for the countries with boreal climate (as Latvia and Lithuania), but nevertheless the species already exists in Estonia. The rest of the countries where A. nebulosus has not established populations for now, the risk to become invasive depends of the future introductions or if it spreads naturally (Luxembourg, Croatia, Cyprus, Malta are countries with similar conditions to the countries where it already established populations).

A. natalis has all the characteristics of a successful invader (abundant in its native range; capable of securing and ingesting a wide range of food; broad native range; highly adaptable to different environments; highly mobile locally; habitat generalist), so it could establish in any country where A. melas and A. natalis (very similar species) are established.About A. catus there is less information because for now it has not established populations in Europe but it has the same characteristics of a successful invader of

11








the other species of Ameiurus. So we can assume that it could become invasive in any country where introduced.

In conclusion for all Ameiurus species there is a major risk of becoming invasive in any European country once introduced.

12


SECTION A – Organism Information and Screening

Stage 1. Organism Information RESPONSE[chose one entry, delete all others]

COMMENT

1. Identify the organism. Is it clearly a single taxonomic entity and can it be adequately distinguished from other entities of the same rank?

Yes.This Risk Assessment refers to genus Ameiurus and includes information about the most representative species, species that have been introduced in Europe and established populations in at least one country.

The genus Ameiurus (Rafinesque, 1820) is part of Siluriformes Order (silures, catfishes) and Ictaluridae Family (Gill, 1861) – bullhead catfishes, North American freshwater catfishes.

From the Integrated Taxonomic Information System (http://www.itis.gov) Ameiurus spp. comprises the following species:

Ameiurus brunneus Jordan, 1877 – snail bullhead Ameiurus catus (Linnaeus, 1758) – white catfish, white bullhead Ameiurus melas (Rafinesque, 1820) – black bullhead Ameiurus natalis (Lesueur, 1819) – yellow bullhead Ameiurus nebulosus (Lesueur, 1819) – brown bullhead Ameiurus platycephalus (Girard, 1859) – flat bullhead Ameiurus serracanthus (Yerger and Relyea, 1968) – spotted

bullhead

Ictaluridae comprises eight genera (one extinct) and 67 species—51 living (12 with fossil records) and 16 extinct (Arce-H. et al., 2016). Monophyly of living Ictaluridae is well supported by molecular data analysed using parsimony and model-based methods. These analyses found further support for the monophyly of the genus Ameiurus. This genus is represented by16 species of which nine are fossils. Within Ameiurus, the basal split is between A. pectinatus, the oldest fossil species, and all other species. At the next higher node is a split between a clade with A. reticulatus plus A. natalis and a second clade with all the other species included in the analysis (Arce-H. et al., 2016).

All bullhead species have an adipose fin between their dorsal and tail fins. This small fleshy fin lacks any hard, internal structures such as bone

13


https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=163995


or cartilage. Bullheads have a rounded tail which will help distinguishing them from small channel catfish that have a forked tail. Bullheads have no scales, their bodies are covered with taste buds, and will be very slippery to handle. Finally, bullheads have a single, sharp spine in the dorsal and pectoral fins. Like other members of the Catfish Family, bullheads also have barbels (‘whiskers’) under their chin that help them located food (Minnesota Department of Natural Resources, 2016).

Some species could be misidentified as Ictalurus (Rafinesque, 1820 – channel catfishes, forktail catfishes), a genus of the same family: Ictaluridae, (Gill, 1861). For instance I. punctatus (channel catfish) has been known to mate with brown bullhead (Ameiurus nebulosus), yellow bullhead (Ameiurus natalis), and black bullhead (Ameiurus melas), resulting in a variety of hybrid catfish (Florida Museum of Natural History. Online: https://www.flmnh.ufl.edu/fish/discover/species-profiles/ictalurus-punctatus/)

With regard to the Ameiurus genus, the problem is with brown and black bullheads, given difficulties to identify Ameiurus species (Lenhardt et al, 2011).

One of the main distinguishing features separating Ameiurus melas and Ameiurus nebulosus is that the black bullhead is with rough or irregular small barbs on the trailing edge of the pectoral spines weak; whereas for the brown bullhead, the pectoral spike edge is with regular saw-like barbs. Other distinguishing features include the number of anal ray fins; the black bullhead has 15-21 anal ray fins, the brown bullhead 21-24. The colour pattern also varies with black bullhead being mainly solid and dark, with a white or yellow belly; faint pale yellow vertical bar at base of tail while the brown bullhead is usually mottled, but may be solid, generally yellow brown or grayish, belly usually cream or tan; no bar at base of tail (CABI, 2015a).

14





Ameiurus natalis is similar to the black bullhead, A. melas and brown bullhead, A. nebulosus. A. natalis can be distinguished from these species by its cream-white chin barbels. A. melas has dusky or black chin barbels, a rounded anal fin and fewer anal rays (19-23) and rakers on the first gill arch (15-21). A. nebulosus, is usually mottled on the side of the body, has dusky or black chin barbels and fewer anal rays (19-23) (CABI, 2009).

Brown bullheads (Ameiurus nebulosus) are known to hybridize naturally with closely related black (Ameiurus melas) and yellow bullhead (Ameiurus natalis) species (Hunnicutt et al., 2005).

The species in the same genus are sometimes very difficult to distinguish one from another (especially A. melas and A. nebulosus).

Ameiurus melas (Rafinesque,1820)EN: Black bullhead, DE: Schwarzer Katzenwels, FR: Poisson-chat, IT:Pesce gatto, ES:Pez gato negro.

Ameiurus nebulosus (Lesueur, 1819)EN: Brown bullhead; DE: Brauner Katzenwels; FR: Barbotte brune; ES: Pez gato; Barbú torito.

Ameiurus natalis (Lesueur, 1819)EN: Yellow bullhead; DE: Gelber Katzenwels; FR: Barbotte jaune; IT: Pesce gatto; ES: Cabeza de toro; Pez gato; Bagre torito amarillo.

Ameiurus catus (Linnaeus, 1758) – EN: White catfish, White bullhead; DE: Weiße Katzenwels; FR: Poisson-chat blanc; IT: Pesce gatto; ES: Barbú cabezón.

2. If not a single taxonomic entity, can it be redefined? (if necessary use the response box to re-define the organism and carry on)

NA

15

http://www.fishbase.org/ComNames/CommonNameSummary.php?autoctr=312068






https://www.itis.gov/servlet/SingleRpt/RefRpt?search_type=author&search_id=author_id&search_id_value=5559


3. Does a relevant earlier risk assessment exist? (give details of any previous risk assessment)

No Using an invasiveness screening tool for freshwater fishes the black bullhead has been ranked in several European countries/regions as representing a high risk of being invasive, including Belgium, Iberia, and the UK, but medium risk in Finland. This invasiveness is demonstrated in some countries, e.g. France where it is among the few freshwater fish listed with a legal status of ‘invasive’. Whereas in the UK, only one of a few reported populations has been confirmed, though the species has nonetheless been the subject of regulation since the 1980s. Data on that lone population in England is limited to morphology and an initial study of gonad development and dietary breadth (Ruiz-Navarro et al. 2015).

A Risk Assessment for Ameiurus melas has been conducted in Balkans Region and the result was that the species has medium-high risk to become invasive (Simonović et al., 2013), Applying FISK v2 to the Iberian Peninsula, Almeida et al. (2013) classified A. melas as with “very high” invasive risk (maximum categorical score)

Ameiurus melas is categorized as “high risk” and Ameiurus nebulosus as “moderately high risk” of being invasive applying the Fish Invasiveness Screening Kit (FISK) in the drainage basin of Lake Balaton (Hungary). (Ferincz et al., 2016).

Verbrugge et al. (2012) carried out a comparison of available risk classifications for fish in various countries, where risk assessment protocols in force have been applied in their national context.

BE1 DE2 AT2 FISK/FI-ISK

UK4 IE5 CH6

Ameiurus nebulosus (Lesueur, 1819)

Watch list

Black list

Grey list

High risk4

n.r. Medium risk

n.a.

BE: Belgium, DE: Germany, AT: Austria, UK: United Kingdom, IE: Ireland, CH: Switzerland; n.a.: not applicable because protocol is limited

16


to only one taxonomic group; n.r.: not reviewed. 1 Harmonia Database (2010); 2 Nehring et al. (2010) for fish species; 4 Non-native Species Secretariat (2010); 5 Invasive Species Ireland (2007); 6 Swiss Commission for Wild Plant Conservation (2008); (Verbrugge et al., 2012)

Verbrugge et al. (2012) indicates that risk classifications from one region cannot be applied to other regions without inserting a caveat.

Ameiurus nebulosus is categorized as “high risk” of being invasive in Greece applying FISK (Perdikaris et al., 2016).

Ameiurus melas is categorized as “high risk” and Ameiurus nebulosus as “high risk” of being invasive applying FISK in Croatia and Slovenia. (Piria et al., 2016).

4. If there is an earlier risk assessment is it still entirely valid, or only partly valid?

No In the study in Balkan region they only consider single countries.This present Risk Assessment pretends to actualize the information for all the EU countries about A. melas, and encompass the genus Ameiurus.

5. Where is the organism native? North America Ameiurus melas:Native to the Great Lakes, Hudson Bay, and Mississippi River basins in most of the eastern and central United States and adjacent southern Canada and northern Mexico, south to the Gulf Coast (Gulf Coast drainages from Mobile Bay in Georgia and Alabama to northern Mexico) (Page and Burr, 2011); apparently not native to the Atlantic Slope.

Native to Canada, USA and Mexico (CABI, 2015a).

Native Range: Great Lakes, Hudson Bay, and Mississippi River basins

17


from New York to southern Saskatchewan and Montana, south to Gulf; Gulf Slope drainages from Mobile Bay, Georgia and Alabama, to northern Mexico. Apparently not native to Atlantic Slope (Fuller and Neilson, 2017a).

Ameiurus nebulosus:Native to North America: Atlantic and Gulf Slope drainages from Nova Scotia and New Brunswick in Canada to Mobile Bay in Alabama in USA, and St. Lawrence-Great Lakes, Hudson Bay and Mississippi River basins from Quebec west to Saskatchewan in Canada and south to Louisiana, USA (Froese and Pauly, 2016).

Northamerica (CABI, 2015b)

Native Range: Atlantic and Gulf Slope drainages from Nova Scotia and New Brunswick to Mobile Bay, Alabama, and St. Lawrence Great Lakes, Hudson Bay, and Mississippi River basins from Quebec west to southeastern Saskatchewan, and south to Louisiana. This species may have been originally absent from all or part of the Gulf Coast west of the Apalachicola and east of the Mississippi River. This speculation is based on the very spotted distribution of the species both in panhandle Florida and Alabama and the fact that it appears to be largely confined to reservoirs in Alabama. In its native range in peninsular Florida it is found primarily in larger bodies of water; Whereas, on the Atlantic Slope in Florida, this species is found in both streams and sloughs (Fuller and Neilson, 2017b).

Ameiurus natalis:Native throughout most of the eastern and central USA and south eastern Canada, maybe New Hampshire (where has been recorded as native (Scarola, 1973; Scott and Crossman, 1973) but also as introduced (U.S. Geological Survey, 2015).

18


Ameiurus natalis, a species of bullhead catfish, is native throughout most of the eastern and central USA and south eastern Canada (CABI, 2009)

Native Range: Atlantic and Gulf Slope drainages from New York to northern Mexico, and St. Lawrence Great Lakes and Mississippi River basins from southern Quebec west to central North Dakota, and south to Gulf (Fuller and Neilson, 2017c).

Ameiurus catus:Atlantic and Gulf Slope drainages from lower Hudson River, New York, to Apalachicola basin in Florida, Georgia, and Alabama; south in penin-sular Florida to Peace River drainage (modified from Page and Burr 1991).

Native Range: Atlantic and Gulf Slope drainages from lower Hudson River, New York, to Apalachicola basin in Florida, Georgia, and Al-abama; South in peninsular Florida to Peace River drainage (Fuller and Neilson, 2017c).

6. What is the global distribution of the organism (excluding Europe)?

North and South America, Canada, Europa, Asia, Oceania, Pacific Islands

Ameiurus melas:Introduced widely outside the native range. (Rose, 2006). Apart of Europe, it has been introduced also in Chile (Welcomme, 1988; Froese and Pauly, 2004), Mexico (Page and Burr, 1991; Froese and Pauly, 2004) and many states in the USA.

Ameiurus nebulosus:It has been introduced outside of its native range in North America to other areas of North America, Europe, Asia and Pacific islands (i.e. New Zealand, Hawaii). Also Chile, Iran and Turkey (Salvador, 2015; Froese and Pauly, 2016).

Ameiurus natalis:Introduced into at least 14 states in the USA outside of its native range

19








(Fuller et al., 1999), in addition to southwestern British Columbia (Hanke et al., 2006). Also it has been introduced in Mexico, as an aquaculture species (FAO, 1997).

Ameiurus catusIt was introduced in many states in USA (USGS, 2016), in Puerto Rico (Erdsman, 1984) and Mexico (Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, 2016).

7. What is the distribution of the organism in Europe?

See question 1 of EU CHAPEAU.

Ameiurus melas:Widely distributed across Europe: Austria, Germany, Bulgaria, Poland, Belgium, France, Italy, The Nether-lands, UK, Portugal, Spain, Croatia, Slovenia, Czech Republic, Ro-mania, Hungary, Slovakia, Denmark, Finland, Ireland, possible Greece, Balkan countries, Albania and Turkey.

Ameiurus nebulosus:

Kottelat and Freyhof (2007) indicated that it is established in Germany, Italy and Finland. Although (CABI, 2015b) mention that it is established in many European countries, A. nebulosus has often been mistaken for A. melas (See Rutkayová et al., 2012). The unclear taxonomic status of both A. melas and A. nebulosus resulted in more doubts about the occurrence of these species in some countries (Rutkayová et al., 2013).

Conversely, some authors consider it widely distributed across Europe: from the Iberian Peninsula till the European part of Russia, Switzerand, Turkia, Balkan countries and more recently in Greece (Barbieri, 2015)

Having in mind the possible mistakes already done with this species, we found bibliography about its record in Belgium, Bulgaria, Netherlands, UK (Olenin et al., 2008); Austria, Poland, Portugal, Spain, Italy, France, Germany, Czech Republic (Froese and Pauly, 2016); Croatia, Slovenia (Piria et al, 2016); Estonia, Ireland, Slovakia, Sweden (Secretariat of NOBANIS, 2012); Bulgaria, Finland, Romania (GLOBAL INVASIVE SPECIES, 2016); Luxembourg (Ries et al, 2014); Greece (Barbieri,

20


2015).

Ameiurus natalis:There are a number of reports of its introduction into Italy (Welcomme, 1988; Holcík, 1991). Gandolfi et al, 1991) also informed about the oc-currence of the yellow catfish in Italy. Thirteen years later the species is confirmed as established in Italy (Elvira, 2001).

Ameiurus catusUK (Britton and Davies, 2006); Poland (Nowak et al. 2008, 2010).There is no information available about his spread to other countries, but confusion between species could be possible, so identification of other species in the genus as A. melas or A.nebulosus cannot be discarded.

Except for Latvia, Letonia (not confirmed), Malta and Cyprus (no in-formation), in every European country at least one species of Ameiurus has been introduced.

8. Is the organism known to be invasive (i.e. to threaten organisms, habitats or ecosystems) anywhere in the world?

Yes Ameiurus melas and A. nebulosus are recognized as succesfull invaders in Europe (Invasive Species Specialist Group, 2009). Ameirus nebulosus is included in the watch list of Belgium (Branquart, 2016).

Aquatic macroinvertebrates (mainly Chironomidae) dominated the black bullhead´s diet in all size-classes and sites, irrespective of natural river-ine or artificial lentic habitats. Secondary prey items were responsible for the observed between-sites (microcrustaceans in artificial lentic habitat; oligochaeta and caddisfly larvae in natural riverine habitats) and onto-genetic diet differences (from microcrustaceans to larger prey). It con-sumed plant material, terrestrial prey and co-occurring fish species (nat-ive or exotic) and thus they could be considered as generalist or oppor-tunistic, foraging on the most abundant and available prey. It can negat-ively affect native (Iberian) ichthyofauna throughout direct predation and competition (Leunda et al., 2008).

The fishery in North London had succumbed to a highly efficient in-vader, A. melas, and the local angling club had lost one of their best fish-eries.

21


(https://marinescience.blog.gov.uk/2015/08/07/eradicating-black-bull-head-catfish/).

The high flexibility in the life history of the black bullhead as demon-strated by its non-native populations, as well as its extreme tolerance and capability to live in systems with poor water quality, suggests that this species has a high potential to invade new areas and establish viable pop-ulations. (Novomeska and Kovac, 2009).

The great growth and life-history plasticity of black bullhead affords the species great potential to invade and establish viable populations in new areas. A species tolerant of pollutants, low dissolved oxygen (3.0 mg L-1), and elevated water temperatures (up to 35 ºC) the black bullhead also has a specialized, nest-guarding, reproductive strategy. Many of the in-troduced fishes in Europe are nest-guarders, which suggests that black bullhead has the potential to be highly invasive and exert impacts to eco-system function through increased turbidity (Copp et al., 2016)

Ameiurus nebulosus is a generalist omnivore, feeding mostly at night and eating benthic organisms that occur frequently within freshwaters: waste, molluscs, immature insects, terrestrial insects, leeches, crusta-ceans, worms, algae, plant material, fishes and fish eggs (Scott and Crossman, 1973). Young (30-60 mm total length) prefer chironomid lar-vae, ostracods, amphipods, mayflies and other small aquatic inverteb-rates (Scott and Crossman, 1973).

This omnivorous fish species can form very dense populations and is able to dominate freshwater fish communities. Diet of large-sized bull-heads has been found to consist almost exclusively of juvenile fishes. (Anseeuw et al., 2007).

For those reasons A. nebulosus is considered a pest in Poland, and fisher-ies legislation forbids release of this species into the wild. (Nowak et al, 2010).

22

https://marinescience.blog.gov.uk/2015/08/07/eradicating-black-bullhead-catfish/



The ecological effects of A. melas seem potentially close to the A. nebu-losus (Nowak et al, 2010).

Several countries (Switzerland (Wittenberg, 2005); Poland (FAO, 1997); Chile (Welcomme, 1988)) report adverse effects on native fish com-munities following its establishment.(http://www.cabi.org/isc/datasheet/94468)

Related to the distribution of brown bullhead, its decline in some European countries, e.g. Belgium, Czech Republic and Poland, has coin-cided with an increase in the distribution and abundance of black bull-head in Central and Eastern Europe; these contrasting patterns have led to suggestions that black bullhead is displacing brown bullhead. How-ever, the two species have overlapping native distributions so this may simply be coincidental. However, further study is needed to determine whether or not this is artifact or indicative of black bullhead displacing brown bullhead (Copp et al., 2016)

Ameiurus natalis is known to eat minnows, crayfish, insects, and larvae of insects, aquatic invertebrates, worms and more aquatic vegetation (macroalgae) then the other bullheads.The yellow bullhead was largely introduced in other North American countries where it is not-native. At least one country reports adverse ecological impact after introduction of Ameiurus natalis in North America (Froese and Pauly, 2016)

Ameiurus catusWhite catfish is apparently responsible for the disappearance of Sacra-mento perch Archoplites interruptus in Thurston Lake, California (Mc-Carraher and Gregory, 1970).Following the literature data, ictalurids are nocturnal zoophagophores, consuming all animals in the water column whose size allows the species to consume them. Besides invertebrates, among which insect larvae are

23

http://www.cabi.org/isc/datasheet/94468


preferred, ictalurids feed on molluscs and fishes, as well as algae, plant material and terrestrial invertebrates (Scott and Crossman, 1973; Brylin-ski and Chybowski, 2000; Kottelat and Freyhof, 2007; Leunda et al., 2008; Ruiz-Navarro et al. 2014). Ameiurus species are predators of small fishes and larvae that show identical microhabitat requirements (Leunda et al., 2008).

Moreover, they are vectors of alien parasites (Scholz and Cappellaro, 1993; Uzunova and Zlatanova, 2007; Sheath et al., 2015).

In resume the bullheads could negatively affect native ichthyofauna throughout direct predation and competition (Leunda et al, 2008).

The characteristics of a successful invader, well demonstrated for A. melas and A. nebulosus could be met in the case of other species of Ameiurus genus.

Collier and Grainger (2015) identify A. nebulosus with a high overall risk in New Zealand.

In Japan is an uncategorized alien species and needs a detailed investiga-tion by the Japan Government before importation (https://www.en-v.go.jp/nature/intro/4document/files/r_yunyu2.9_e.pdf).

9. Describe any known socio-economic benefits of the organism in the risk assessment area.

Fishing – low benefits Low benefits in sport fishing and very low in pet trade.

As they are so tolerant to poor water conditions, the bullheads may accumulate the pollutants in their bodies. Therefore, in some waters, bullheads contain elevated levels of contaminants. The New York State Department of Health has issued an advisory with recommendations for limiting consumption of contaminated fish. So it seems that they no longer represent an economic value.

24

https://www.env.go.jp/nature/intro/4document/files/r_yunyu2.9_e.pdf

https://www.env.go.jp/nature/intro/4document/files/r_yunyu2.9_e.pdf


Ameiurus melas:Black bullhead (Ameiurus melas formerly Ictalurus melas), a species which is very close to brown bullhead (Ameiurus nebulosus), is farmed in Italy in open farms (production in Italy for 2010 estimated in 250 tons) (EFSA, 2011).

Ameiurus nebulosus:Economic benefits from aquaculture occur primarily within Chile, China, Bulgaria and Belarus (Welcomme, 1988; Tan and Tong, 1989; Reshetnikov et al., 1997; Mikhov, 2000), although the magnitude of these benefits remains uncertain. Introduced populations of A. nebulosus to Europe and some Pacific islands originally provided social benefits as sportfish (Welcomme, 1988), but their current social value as sportfish within their introduced range is low and has poor economic value. Within their native range, the species may be held within zoos or public aquariums (CABI, 2015b).

Ameiurus nebulosus is popular in some areas as a gamefish. Reportedly a good eating fish, especially when smoked (Global Invasive Species, 2006).

Ameirus melas and Ameirus nebulosus is only a main species used in aquaculture in Italy, and not in Slovenia or Croatia (Bianco and Ketmaier, 2016).

Ameiurus natalis:This species is of low economic importance as a food fish, stocking into ponds, aquaculture and commercial aquarium trade. A. natalis is extensively used as a laboratory animal for toxic chemicals and medical experiments.

Ameiurus natalis is considered good to eat and may be sought by some fishermen. It is of low economic importance as a food fish, stocking into ponds, aquaculture and commercial aquarium trade. A. natalis is extensively used as a laboratory animal for toxic chemicals and medical

25


experiments (CABI, 2009).

The yearly European aquaculture production and value of Black bullhead Ameiurus melas (average of 2000–2004) is in the ninth position (473.4 tons; 1,770.7 thousands US$; 3.74 US$ kg–1) (Turchini et al, 2008).

In European inland aquaculture, there are American native finfish species supporting a relatively good production (1,292 tons/year in the 5-year period 2000–2004) (Turchini et al., 2008).

The impacts of aquaculture on biodiversity and particularly the utilization of alien species for culture purposes are of current and increasing concern, and the consequences of decreasing or changing biodiversity are well known to be potentially devastating. It has been speculated that the presence of alien fish can be a reliable indicator of river health and therefore the wellbeing of European inland waters can be considered to be at high risk (Turchini et al., 2008).

Variable results have been accomplished by species introductions, depending on the species and geographic area. Only a few finfish species are generally recognized as beneficial from a socio-economic viewpoint, usually by improving fishing or aquaculture opportunities. In natural waters, the introductions have resulted in many cases in economically profitable fisheries, although most introductions have failed or led to unwanted consequences in the form of reduced or collapsed native fish stocks (Turchini et al., 2008). Bullfish are not between the species that historically dominated the European aquaculture and that nowadays they don’t represent an alternative to the almost unprofitable rainbow trout and carp farming. At the same time, in recent years, in the complex panorama of European inland aquaculture, the appearance of new exotic species for culture purposes should be considered with concern (Turchini et al., 2008).

26


SECTION B – Detailed assessment

PROBABILITY OF ENTRY

Important instructions: Entry is the introduction of an organism into Europe. Not to be confused with spread, the movement of an organism within Europe. For organisms which are already present in Europe, only complete the entry section for current active pathways of entry or if relevant potential future

pathways. The entry section need not be completed for organisms which have entered in the past and have no current pathways of entry.

QUESTION RESPONSE[chose one entry, delete all others]

CONFIDENCE[chose one entry, delete all others]

COMMENT

1.1. How many active pathways are relevant to the potential entry of this organism?

(If there are no active pathways or potential future pathways respond N/A and move to the Establishment section)

Aquaculture, fisheries …

low Introductions of black bullhead have historically been for either aquaculture, recreational fishing or as an ornamental species. In European waters, the dispersal mechanism is not clear but spread could be as a result of accidental and illegal introductions or natural dispersion between countries via watercourses (CABI, 2015a)

A. nebulosus was likely spread primarily for recreational angling opportunities. Its spread has been undoubtedly facilitated by its ability to survive low oxygen concentrations for prolonged periods. Its establishment, once introduced, was likely assisted by its generalist, omnivore diet with feeding aided, even in turbid waters, by its chin barbels (CABI, 2015b)

Results based on the morphological characters confirmed the occurrence of A. melas for the first time in the Czech republic freshwaters. In terms of A. melas origin (in case of the Czech Republic), the most probable explanation for its finding in the Lužnice River

27


floodplain might be natural spread of individuals from pond aquaculture, via e.g. pond connecting canals. Thus, it seems likely that A. melas was accidentally imported amongst carp (Cyprinus carpio L.) or tench (Tinca tinca L.) from countries where it already widely occurs, such as Hungary or Romania (Wilhelm, 1998. In: Musil et al, 2008).

28


PROBABILITY OF ESTABLISHMENT

Important instructions: For organisms which are already well established in Europe, only complete questions 1.15 and 1.21 then move onto the spread section. If uncertain,

check with the Non-native Species Secretariat.

QUESTION RESPONSE CONFIDENCE COMMENT1.15. How widespread are habitats or species necessary for the survival, development and multiplication of the organism in Europe?

widespread high Ameriurus melas inhabits in irrigation channels, lakes, ponds and reservoirs are the principal habitats. Rivers and streams are secondary habitats (CABI, 2015a)

Black bullhead is classed as a warm-water species, and in its native range, the species is found in the downstream sections of smallto-medium-sized streams of low gradient, ponds and backwaters of large rivers and silty, soft bot-tomed areas of lakes and impoundments. Black bullhead are said to be most abundant in smaller water bodies, espe-cially artificial and heavily managed ponds (Copp et al, 2016).

This demersal species inhabits slow-flowing habitats (lim-nophilic) with soft substrata in all riverine and lacustrine environments, including artificial ones such as ponds and reservoirs (Leunda et al., 2008), with an opportunistic diet-ary.

Previous research on black bullhead suggests that it is highly tolerant to environmental degradation and is cap-able of living with poor water quality conditions (Ribeiro et al. 2008).

One of the greatest concerns in the case of the black bull-head, is associated with degraded or impacted ecosystems,

29



which are considered more susceptible to invasion (Moyle, 1986). This facilitates invasions by species such as the black bullhead (Hanchin et al. 2002), which have been found to benefit in growth terms from increasing eu-trophication. Indeed, all of these factors contribute to the black bullhead’s potential as a successful invader (e.g. Gante and Santos 2002; Koščo et al. 2004; Dextrase and Mandrak, 2006).

Black bullhead has a great potential to invade and establish viable populations in new areas, and this is facilitated by life-history plasticity. However, the risk posed by black bullhead will vary according to local environmental condi-tions, and this is apparent in the FISK rankings of this warm-water species, which is perceived in the north of Europe (Finland) as posing a lower risk of becoming in-vasive than in countries of intermediate or lower latitudes.

Across Europe, numerous dams were constructed for river regulation and as hydropower plants, which lead to water flow lag. Since black bullhead inhabits soft substrates of sluggish sections of creeks and rivers, as well as backwa-ters, channels, swamps and impoundments, this was excel-lent opportunity for further expansion of its range (Cvijan-ovic et al., 2008).

Ameiurus nebulosus inhabits brackish waters and estuaries are secondary habitats as irrigation channels. Principal habitats are lake, ponds, reservoirs, rives and streams (CABI, 2015b).

Ameiurus natalis inhabits irrigation channels, lakes, ponds, reservoirs rivers and streams (CABI, 2015c).

30







Suitable habitats are present and widely distributed in the Risk Assessment Area for Ameiurus spp.

1.21. How likely is it that biological properties of the organism would allow it to survive eradication campaigns in Europe?

very likely high Ameiurus melas

As compiled in Nowak et al (2010), Ameiurus melas is a typical limnophilic and one of the most tolerant fish spe-cies capable of resisting water pollution (Ribeiro et al., 2008). Due to their high fecundity and ecological plasti-city, both A. melas and A. nebulosus are considered invas-ive species.

The black bullhead has several characteristics associated with successful invaders (Ribeiro et al., 2008), such as high reproductive potential, parental care, opportunistic feeders, aggressive behaviour and considerable tolerance to water pollution, turbidity, low oxygen concentration, elevated temperatures and a range of pH values (Novomeská et al., 2013). Its spread has been undoubtedly facilitated by its ability to survive low oxygen concentrations for prolonged periods (Scott and Crossman, 1973).

Ameiurus nebulosus

Once introduced, A. nebulosus is easy to establish thanks to its generalist, omnivore diet, even in turbid waters, as-sisted by its chin barbels (Scott and Crossman, 1973). Conversely, its stout shape and strong dorsal and pectoral fin spines would minimize predation by native predators. Its parental care of eggs and young would also reduce mortality in the young (Scott and Crossman, 1973).

It is nearly impossible to eradicate them when it is estab-

31


lished in a river. In small, closed waters (e.g. small lakes or ponds), control could be possible. In a fishery in North London the black bullhead have spread, the risk to the wider environment was significant; so a piscicide based eradication was carried out by the Na-tional Fisheries Services Virtual Non-native Species Man-agement Team in May 2014. It seems they managed to re-move the only known population of the highly invasive black bullhead from a fishery in Essex, England (https://marinescience.blog.gov.uk/2015/08/07/eradicating-black-bullhead-catfish/).

As compiled in Nowak et al (2010), Ameiurus melas is a typical limnophilic and one of the most tolerant fish spe-cies capable of resisting water pollution (Ribeiro et al., 2008). Due to their high fecundity and ecological plasti-city, both A. melas and A. nebulosus are considered invas-ive species (Gante and Santos, 2002; Koščo et al., 2004; Dextrase and Mendrak, 2006).

The black bullhead has several characteristics associated with successful invaders (Ribeiro et al., 2008), such as high reproductive potential, parental care, opportunistic feeders, aggressive behaviour and considerable tolerance to water pollution, turbidity, low oxygen concentration, elevated temperatures and a range of pH values (Novomeská et al., 2013). Its spread has been undoubtedly facilitated by its ability to survive low oxygen concentrations for prolonged periods (Scott and Crossman, 1973).

The characteristics of successful invaders are common to at least four of the species of Ameiurus, so we can affirm that biological properties of the genus would allow it to

32





survive eradication campaigns in Europe.

33


PROBABILITY OF SPREAD

Important notes: Spread is defined as the expansion of the geographical distribution of a pest within an area.

QUESTION RESPONSE CONFIDENCE COMMENT

2.1. How important is the expected spread of this organism in Europe by natural means? (Please list and comment on the mechanisms for natural spread.)

major high Once established in a basin it is to expect a natural expansion in it. It has several characteristics common to successful invaders, which increases their invasive potential. A. melas and A. nebulosus can tolerate poor river conditions, wide temperature tolerance and a lack of native competitors and predators can facilitate their range expansion along Europe.

Ameiurus melas

In European waters, the dispersal mechanism is not clear but spread of A. melas could be as a result of accidental and illegal introductions or natural dispersion between countries via watercourses (CABI, 2015a)

The black bullhead occurred (imported for aquaculture) in Europe, at first, in France (1871) (Coucherousset et al., 2006). The species expanded relative slowly, however nowadays this is the most widespread North American ictalurid catfish in Europe (Pedicillo, 2008). The expansion was human helped in some cases, while in other situations, a slow, self – managed spreading was observed: for example in Spain (first recorded in 1984 (Elvira 1984) and Portugal (first recorded in 2002 (Gante and Santos 2002).

Black bullhead (Ameiurus melas) was introduced to a

34


western Hungarian fish culture in the beginning of the 1980s, and escaped specimens spread rapidly along the Danube. Abundant stocks have developed in most of the backwaters along the Danube (Bódis et al., 2012).

The species will undoubtedly increase its introduced range through natural dispersal within drainage networks. The magnitude of spread will be dependent upon the spatial configuration of potential habitats and their connectivity via drainage networks. Most natural dispersal within the native range of Canada and the USA has occurred at local levels (Fuller et al., 1999).

Ameirus nebulosus

In European waters, the dispersal mechanism is not clear but spread could be as a result of accidental and illegal introductions or natural dispersion between countries via watercourses (Nowak et al., 2010; Copp et al., unpublished). Recently, in Greece, a self-sustained population of A. nebulosus was discovered and is supposed that the fish was introduced from Bulgaria through the transboundary waters of the Strymon River (Barbieri, 2015).

It is to be noted that once the species reached the Danube River, the Rhine-Main-Danube Canal offers no physical barrier to the spreading of this invasive species to Western Europe (Müller et al., 2002).

The black bullhead occurred (imported for aquaculture) in Europe, at first, in France (1871) (Coucherousset et al., 2006). The species expanded relative slowly, however nowadays this is the most widespread North American ictalurid catfish in Europe (Pedicillo, 2008). The expansion was human helped in some cases, while in other situations, a

35


slow, self – managed spreading was observed: for example in Spain (first recorded in 1984 (Elvira 1984) and Portugal (first recorded in 2002 (Gante and Santos 2002).

The species will undoubtedly increase its introduced range through natural dispersal within drainage networks. The magnitude of spread will be dependent upon the spatial configuration of potential habitats and their connectivity via drainage networks. Most natural dispersal within the native range of Canada and the USA has occurred at local levels (Fuller et al., 1999).

European introductions of A. nebulosus occurred concurrently, with individuals from North America introduced to Germany for angling, sport and aquaculture in 1885 (Scott and Crossman, 1973), leading to subsequent intentional and unintentional secondary spread to the rest of Europe. A. nebulosus is a moderately strong swimmer (Scott and Crossman, 1973) that is capable of surviving degraded, warmwater freshwater environments; therefore, the species will undoubtedly increase its introduced range through natural dispersal within drainage networks. The magnitude of spread will be dependent upon the spatial configuration of potential habitats and their connectivity via drainage networks. Most natural dispersal within the native range of Canada and the USA has occurred at local levels (Fuller et al., 1999).

Ameiurus nebulosus is a moderately strong swimmer that is capable of surviving degraded, warmwater freshwater environments; therefore, the species will undoubtedly increase its introduced range through natural dispersal within drainage networks. The magnitude of spread will be dependent upon the spatial configuration of potential

36


habitats and their connectivity via drainage networks. Most natural dispersal within the native range of Canada and the USA has occurred at local levels.

A. natalis are sedentary fish which may disperse naturally over short distances (CABI, 2009).

2.2. How important is the expected spread of this organism in Europe by human assistance? (Please list and comment on the mechanisms for human-assisted spread.)

moderate medium The species in this genus was likely spread primarily for recreational angling opportunities.

The intentional stocking of A. melas for recreational fishing purposes has reduced in recent years. In Czech Republic, quite recently, evidence was obtained on unintentional introduction of Ameiurus melas with carp stock from Croatia to the fishponds in the Třeboň district in 2003 (Koščo et al. 2004; Lusk et al, 2010). The expansion was human helped in some cases, for example it was imported to Hungary from Italy in 1980 (Harka 1997).

A.nebulosus was first introduced in the Pacific islands (1877) with the release of 100-200 individuals for angling in Auckland, New Zealand. These introductions resulted in local viable populations by 1885 (Holcík, 1991). Additional introductions for angling and sport occurred in Hawaii in 1893 (Welcomme, 1988).

The intentional stocking of A. melas for recreational fishing purposes has reduced in recent years. In Czech Republic, quite recently, evidence was obtained on unintentional introduction of Ameiurus melas with carp stock from Croatia to the fishponds in the Třeboň district in 2003 (Koščo et al. 2004; Lusk et al, 2010). The expansion was human helped in some cases, for example it was imported to Hungary from Italy in 1980 (Harka 1997).

37


Although angling for A. nebulosus within Canada is relatively unpopular (Scott and Crossman, 1973), the initial introduction to Europe and the Pacific islands for angling suggests almost global popularity as a sportfish; therefore, unauthorized introductions for angling purposes may occur.

The Brown bullhead (Ameiurus nebulosus) was introduced to Hungary in 1902 and rapidly spread in natural waters because of stockings for recreational reasons (Bódis et al., 2012).

There have been intentional and unintentional, human‐mediate species introductions. Fishes are dispersed beyond their native ranges because they are interesting sporting species, for example, Ameiurus used in aquaculture (Bianco and Ketmaier 2016).

Introduction via fisheries (angling/sport purposes) and aquaculture are the dominant long-distance (national; international) vectors. Intentional introductions by fisheries managers may result in long-distance travel events via stocking from source populations. Aquaculture introductions may have similar magnitudes of spread. For example, China (Beijing and Hubei province) stocked A. nebulosus for aquaculture purposes from USA broodstock. Unauthorized introductions by anglers also has the potential to contribute to local, national or international events but may be constrained by the effectiveness of certain legal restrictions that prohibit import of live organisms across borders (CABI, 2015b).

The natural expansion of the Brown bullhead (Ameiurus nebu-losus) was assisted by intentional introductions carried out by angling associations, fish pond´s owners, accidental admixture

38


to the stocking material of the other species and using it as a live bait (Hanel et al., 2011).

Intentional stocking has been reported in case of A. natalis as this species can be introduced into degraded watercourse due to their high tolerance to pollution (Klossner, 2005).

Ameiurus natalis is easy to identifty in shipments of tropical fish and fish to be stocked for anglers and is therefore unlikely to be accidentially introduced into new areas.

A. natalis have been intentionally introduced in new waterways by several pathways, including releases from aquariums and intentional stocking in open waters for food and game fish (CABI, 2009).

Ameiurus catus

Accidental movement of either their eggs or larvae via anglers’ nets is believed to be the mechanism by which Ameiurus catus may be released (Zięba et al., 2010).

Some countries have forbidden new entries of A. melas and A. neboulosus (France, Poland etc), so we consider that human-assisted spread will become less important.

In conclusion the spread by natural means could be more important that by human assistance.

2.3. Within Europe, how difficult would it be to contain the organism?

very difficult high Once established in a river basin, the bullheads´ control is almost impossible.

The application of trapping and electric fishing to controlling black bullhead Ameiurus melas was relatively effective in a French lake as no compensatory responses

39


were recorded. In contrast, compensatory responses were detected in A. melas populations elsewhere following mass removals.

Thus, where the management aim is suppression of invasive fish populations, then removals can provide an effective short-term measure. Its long-term effectiveness is, however, reduced substantially if the remaining fish exhibit compensatory responses, such as increased survival, growth and fecundity. Correspondingly, long-term population suppression using removals is likely to require sustained management efforts, potentially accruing high resource costs (Davies and Britton, 2015).

Control of A. melas populations within lentic environments is possible. The results of Louette and Declerck (2006) study on “Assessment and control of non-indigenous brown bullhead (Ameiurus nebulosus) populations using fyke nets in shallow ponds” suggest that double fyke nets, when combined with the mark-recapture technique, are a very useful tool for the efficient and reliable assessment of brown bullhead populations. The results of the study also suggest that double fyke nets may potentially be a cost-effective tool for the mass removal of non-indigenous brown bullhead populations. This could be applied also for other species of Ameiurus. Other method that worked was using a piscicide to extirpate an established stillwater population from England in 2014 (see 2.14 for further information).

Ameiurus melas

In a fishery in North London the black bullhead have spread, the risk to the wider environment was significant; so a piscicide based eradication was carried out by the National Fisheries Services Virtual Non-native Species Management

40


Team in May 2014. It seems they managed to remove the only known population of the highly invasive black bullhead from a fishery in Essex, England (https://marinescience.blog.gov.uk/2015/08/07/eradicating-black-bullhead-catfish/).

In England it has been completed an eradication of the only known wild population of black bullhead catfish in England (Essex). In a one day operation, specially trained officers treated the lake with rotenone, a chemical that targets fish, whilst causing little harm to other aquatic life. The work was successful in removing this highly invasive and damaging species. The lake and its native fish had been suffering the impacts of these catfish for some time and angling club members had noticed a drastic decline in the performance of the fishery; including the deterioration in the growth rate, size of native fish, reduced catch rate and the black bullhead as a nuisance. The club contacted the Environment Agency fisheries department and the operation to remove the catfish was planned.

Eradication through piscicides, such as rotenone or through mechanical removal by fishing/angling; the species is reportedly easy to catch. Mass removal has also been considered as a possibility (CABI, 2015a)

Ameiurus nebulosus

Eradication may involve the use of chemical agents (e.g., rotenone) to induce mortality within introduced populations, although such methods should be evaluated for their potential effects on non-target fishes. Other measures (e.g., physical removal using fish sampling gears: fyke nets, seines, boat and backpack electrofishers) may also be effective.

41




Physical control should involve, if possible, physical isolation of introduced populations, which may require physical (e.g., block nets) or electrical barriers.

Biological control of adult A. nebulosus is unlikely given the paucity of natural predators within the native range, although juveniles may be predated upon by certain large-bodied fishes (e.g., Esox spp. within native range) (CABI, 2015b).

Ameirus melas and Ameiurus nebulosus is difficult/costly to control (CABI, 2015a).

Ameiurus natalis

Public awareness is essential for this species to prevent misidentification of this species with A. melas and A. nebulosus. Public awareness is important to prevent establishment of new populations and to prevent further illegal introductions of this species.

Open season fishing for A. natalis is possible and fish can be readily caught using a regular line, by electrofishing or a beach seine. Targeted removal of the young-of-the-year when in tight schools would limit the impact this species has on the habitat.

Chemicals such as rotenone can be applied at a concentration of three parts per million to remove A. natalis but will also eliminate any other fish which you may want to protect. (CABI, 2009).

42


2.4. Based on the answers to questions on the potential for establishment and spread in Europe, define the area endangered by the organism.

[Most of Europe]

high At least 2 species of the genus Ameiurus are established in Europe, A. nebulosus and A. melas, the latter being present in almost all countries. Other 2 (A. natalis and A. catus) have been eventually recorded. See answers to questions 5 and 6 of EU CHAPPEAU

2.5. What proportion (%) of the area/habitat suitable for establishment (i.e. those parts of Europe were the species could establish), if any, has already been colonised by the organism?

33-67 low Given the high proportion of countries where Ameiurus species are established, as well as the possible bad ecological conditions of the habitats where it is found, it is considered that it may be of the order of that proportion.

2.6. What proportion (%) of the area/habitat suitable for establishment, if any, do you expect to have been invaded by the organism five years from now (including any current presence)?

10-33 low Given the recent colonization of the species it is estimated that its colonization in five-years from now may be of this order. The life-history traits of A. melas and A. nebulosus and their plasticity are similar to other successful invaders, which will facilitate range expansion for this species. It is supposed that, if no measures will be taken, other Ameiurus species could have the same success as invaders. Wide en-vironmental tolerances and the fact that suitable habitats are present and widely distributed in the Risk Assessment Area, will also allow a greater number of water bodies to provide suitable habitat for Ameiurus.

2.7. What other timeframe (in years) would be appropriate to estimate any significant further spread of the organism in Europe? (Please comment on why this timeframe is chosen.)

20 low There is not a follow-up of its expansion, but considering the conditions of expansion in which the species occurs, this can be significant in this period.

As included in the article Fishes of the genus Ameiurus (Ictaluridae, Siluriformes) in the Transcarpathian water bodies (Movchan et al, 2014) their expansion in Tisza took place subsequently after almost 50 years, and now there is a new destabilization (deterioration and redistribution) in some ichthyocenoses under the influence of dangerous and aggressive A. nebulosus and A. melas. A. nebulosus gradually became a “victim” of A. melas.

43


In the case of A. natalis its occurrence in Italy was con-firmed in 1988 (Welcomme). So, only thirteen years later the species is confirmed as already established. (Elvira, 2001).

It is to be noted that nowadays the aquatic ecosystems are subject to more deterioration, eutrophication and loss of biodiversity that transform habitats in more suitable for Ameiurus spp.

In Spain (Dana et al., 2016) cited the arrival of A.melas at Majalberraque stream probably due to the natural dispersion that takes advantage of the connection of the rice paddy system and its network of canals with the Guadalquivir. The locality of the Brazo del Este cited by García-de Lomas et al. (2009) is more than 20 kilometers downstream of that, which confirms its dispersion on the Guadalquivir River. It is also very likely that the species is much more widespread in the province of Seville.

2.8. In this timeframe what proportion (%) of the endangered area/habitat (including any currently occupied areas/habitats) is likely to have been invaded by this organism?

10-33 low There is no information about the endangered areas/habitats occupied by the species, but given the endangered situation of the habitats in the river basins in Europe, it is estimated that it could be of the order of this proportion.

2.9. Estimate the overall potential for future spread for this organism in Europe (using the comment box to indicate any key issues).

high medium As compiled in the document Status of Non-Indigenous Fish Species in the Balaton Catchment (http://www.eulakes.eu/upload/eulakes/gestionedocumentale/output%205.2.1%20-%20lake%20Balaton_effects%20of%20climate%20change%20on%20new%20species_784_2181.pdf) the species expanded relative slowly, however nowadays A. nebulosus and A. melas are the most widespread North American ictalurid catfish in Europe (Pedicillo, 2008). The expansion was human helped in some cases, for example A. melas was imported to

44

http://www.eulakes.eu/upload/eulakes/gestionedocumentale/output%205.2.1%20-%20lake%20Balaton_effects%20of%20climate%20change%20on%20new%20species_784_2181.pdf




Hungary from Italy in 1980 (Harka, 1997). In other situations, a slow, self – managed spreading was observed: for example in Spain_ first recorded in 1984 (Elvira 1984) and Portugal- first recorded in 2002 (Gante and Santos, 2002). The bullheads are tolerant of the harsh water conditions (eg. water pollution, low dissolved oxygen levels), omnivorous, aggressive, has parental care and prolonged reproduction period (Braig and Johnson, 2003, Novomenska and Kovac, 2009, Scott and Crossman, 1973). In Hungarian waters it seems that A. melas outcompete the congener brown bullhead (Ameiurus nebulosus) (Harka and Sallai, 2004), this phenomenon is prominent either in the Balaton catchment.

Based on its high flexibility in its life-history traits of A. melas and A. nebulosus, one may assume that the bullheads have a great potential to spread into new environments (Novoneska et al., 2010).

Ameiurus melas is abundant in its native range, capable of securing and ingesting a wide range of food, gregarious, it has a broad native range, it has high reproductive potential, it’s highly adaptable to different environments, it’s invasive in its native range, it is a habitat generalist, it has been proved invasive outside its native range, it’s tolerant of shade (CABI, 2015a)

Ameiurus nebulosus is abundant in its native range, capable of securing and ingesting a wide range of food, fast growing, it has a broad native range, it has high genetic variability, it has high reproductive potential, it’s highly adaptable to different environments, it’s highly mobile locally, it is a habitat generalist, it’s pioneering in disturbed areas,it has been proved invasive outside its native range, it tolerates, or benefits from, cultivation, browsing pressure,

45


mutilation, fire etc (CABI, 2015b).

Ameiurus natalis is abundant in its native range, capable of securing and ingesting a wide range of food, it has a broad native range, it’s highly adaptable to different environments, it’s highly mobile locally, it’s a habitat generalist (CABI, 2009).

46


PROBABILITY OF IMPACTImportant instructions:

When assessing potential future impacts, climate change should not be taken into account. This is done in later questions at the end of the assessment. Where one type of impact may affect another (e.g. disease may also cause economic impact) the assessor should try to separate the effects (e.g. in this

case note the economic impact of disease in the response and comments of the disease question, but do not include them in the economic section). Note questions 2.10-2.14 relate to economic impact and 2.15-2.21 to environmental impact. Each set of questions starts with the impact elsewhere in

the world, then considers impacts in Europe separating known impacts to date (i.e. past and current impacts) from potential future impacts. Key words are in bold for emphasis.

QUESTION RESPONSE CONFIDENCE COMMENTS

2.10. How great is the economic loss caused by the organism within its existing geographic range, including the cost of any current management?

Moderate Low There are no studies where this issue had been calculated.

The Ameirurus spp has the potential to hinder local commercial and sport fisheries through competition with target species.

Global data are no available but in UK the eradication of Ameiurus melas has been developed in a fishery. (http://www.nonnativespecies.org/news/index.cfm?id=151). A fishery in North London succumbed to this highly efficient invader, and the local angling club had lost one of their best fisheries. The operation to remove the catfish costed approx. £5000.00 (€6356.00) £10,000.00, including manpower costs (APHA, personal comm.).

There is potential that Ameiurus melas can have a negative economic impact on communities as this fish can be a 'nuisance' species taking lines/bait intended for other species. Anglers not targeting this species might therefore move on to black bullhead free waters taking not only the money from recreational fishing but

47

http://www.nonnativespecies.org/news/index.cfm?id=151

http://www.nonnativespecies.org/news/index.cfm?id=151


tourism (food, accommodation and transportation) all of which may provide economic opportunities locally (CABI, 2015a).

To date, economic impacts resulting from A. nebulosus introductions have not been quantified. In certain cases of wild establishment, A. nebulosus introductions have the potential to hinder local commercial and sport fisheries through competition with target species (CABI, 2015b).

Van der Veer and Nentwig (2014) don’t find any environmental economic impact of A. melas and A. nebulosus in six environmental and six economic impact categories agriculture, animal production, forestry, human infrastructure, human health and human social life.

2.11. How great is the economic cost of the organism currently in Europe excluding management costs (include any past costs in your response)?

Unknown To date, economic impacts resulting from Ameiurus introductions have not been quantified. In certain cases of wild establishment, A. nebulosus and A. melas introductions have the potential to hinder local commercial and sport fisheries through competition with target species.

For instance A. melas was included in the list of 12 aquatic species potentially causing greatest ecological and economic harm in Great Britain and Ireland (Gallardo and Aldridge, 2013).

Species with high potential impact on water quality as Ameiurus melas are not necessarily those associated with monetary costs (e.g. Neovison vison) with could be more conspicuous for general public.

48


2.12. How great is the economic cost of the organism likely to be in the future in Europe excluding management costs?

Unknown Further studies should be undertaken in relation with water quality.

In the Alqueva Dam their evaluation of both environmental management programmes, and various studies from the region, brought to light a number of underevaluated impacts. It was identified that the transition from flowing to standing water catalyzed the emergence of invasive fish and plant species (Ameiurus melas, Eichhornia crassipes, etc.). - http://ced.berkeley.edu/downloads/research/AlquevaReportLA205-2015.pdf-

In the absence of data for this species, costs for the control of other species of fish are included in an indicative way:

- Current efforts to control topmouth gudgeon in GB amount to £190,000 over 4 years (http://invasivespeciesireland.com/wp-content/uploads/2010/07/Economic_Impact_Assessment_FINAL_280313.pdf)

- In 2010 alone, the US federal government committed $78.5 million in investments to prevent the introduction of Asian carp to the Great Lakes, where they would threaten Great Lakes fisheries and could negatively impact remaining populations of endangered or threatened aquatic species. (https://www.fws.gov/verobeach/PythonPDF/CostofInvasivesFactSheet.pdf).

2.13. How great are the economic costs associated with managing this organism currently in Europe (include any past costs in your response)?

Unknown There are no published studies, other than the work undertaken by the Environment Agency’s Non-native Species Eradication Team (See Comment for Question

49

https://www.fws.gov/verobeach/PythonPDF/CostofInvasivesFactSheet.pdf

https://www.fws.gov/verobeach/PythonPDF/CostofInvasivesFactSheet.pdf

http://invasivespeciesireland.com/wp-content/uploads/2010/07/Economic_Impact_Assessment_FINAL_280313.pdf



http://ced.berkeley.edu/downloads/research/AlquevaReportLA205-2015.pdf-

http://ced.berkeley.edu/downloads/research/AlquevaReportLA205-2015.pdf-


1.21 and 2.14)

The results of Louette and Declerck (2006) study on Assessment and control of non-indigenous brown bullhead (Ameiurus nebulosus) populations using fyke nets in shallow ponds suggest that double fyke nets, when combined with the mark-recapture technique, are a very useful tool for the efficient and reliable assessment of brown bullhead populations. The results of the study also suggest that double fyke nets may potentially be a cost-effective tool for the mass removal of non-indigenous brown bullhead populations. This could be applied also for other species of Ameiurus.

As included in the “Ecological risk assessment of non-indigenous species in Lake Balaton: a pilot study” (http://eulakes-model.eu/media/files/ecological-risk-assessment-of-non-indigenous-species-in-lake-balaton.pdf) the FISK assessments were undertaken independently by the three co-authors. Each person calculated the total FISK scores for each species. Altogether nine species (Carassius gibelio; Perccottus glenii; Anguilla anguilla; Lepomis gibbosus; Neogobius fluviatilis; Gambusia holbrooki; Hypophthalmichtys molitrix x nobilis; Ameiurus melas; Pseudorasbora parva). 5 of the 9 examined fish species (55.6%) – among of them Ameiurus melas- received FISK scores ≥19 (scores between 24 and 33), and thus could be classified as species posing high risk to become abundant in the Balaton catchment. For 6 species (among of them Ameiurus melas), effect on the Catchments seemed to be more significant, which could mean the hardly quantifiable costs of ecosystem services (Farber et al., 2002).

50

http://eulakes-model.eu/media/files/ecological-risk-assessment-of-non-indigenous-species-in-lake-balaton.pdf




2.14. How great are the economic costs associated with managing this organism likely to be in the future in Europe?

Unknown There are no specific studies.

Population suppression, or even removal with sufficient effort, is possible through bio-manipulation of A. melas populations using fyke nets (Louette and Declerck, 2006)

2.15. How important is environmental harm caused by the organism within its existing geographic range excluding Europe?

major medium The ecological effects of A. melas seem potentially close to the A. nebulous.

Introduced Black Bullhead eat endangered humpback chubs Gila cypha in the Little Colorado River, and may exert a major negative effect on the population there (Marsh and Douglas 1997. In Fuller P. and Neilson M., 2017). Minckley (1973), in Fuller P. and Neilson M. (2017) reported that this species is generally considered a pest in Arizona as it forms large stunted populations that compete with more desirable fishes for space and food. Black Bullheads are voracious predators of newly hatched gamefish (Whitmore, 1997. In Fuller P. and Neilson M., 2017). Introduced predatory fishes, including the Black Bullhead, are likely at least partially responsible for the decline of the Chiricahua leopard frog Rana chiricahuensis in southeastern Arizona (Rosen et al. 1995), and have been shown to reduce the abundance and diversity of native prey species in several Pacific Northwest rivers (Hughes and Herlihy 2012. In Fuller P. and Neilson M., 2017).

Van der Veer and Nentwig (2015) find some environmental impacts in herbivory, predation,

51


competition, disease transmission, and ecosystem alteration) of A. melas and A. nebulosus mainly in competition, predation, ecosystem alteration, herbivory and disease transmission.

CABI (2015a) points out the following impacts of Ameiurus melas. The main mechanism is predation. The main outcomes are: conflict, damaged ecosystem ser-vices, ecosystem change/ abitat alteration, modification of natural benthic communities, modification of nutrient regime, negatively impacts, aquaculture/fisheries, re-duced native biodiversity, threat to/loss of endangered species and threat to/ loss of native species.

CABI (2015a) points out the following impacts of Ameiurus nebulosus: The main mechanisms are competition – monopolizing resources, interaction with other invasive species and predation. The main outcomes are altered trophic level, damaged ecosystem services, ecosystem change/habitat alteration, and modification of natural benthic communities, negatively impacts aquaculture/fisheries, reduced native, biodiversity, threat to / loss of endangered species and threat to / loss of native species.

Global Invasive Species (2006) doesn’t find any hard evidence of environmental impacts caused by these brown bullheads, although there is some concern that may negatively affect trout fisheries, freshwater crayfish and eels.

White Catfish were apparently responsible for the dis-appearance of Sacramento perch Archoplites interrup-tus in Thurston Lake, California (McCarraher and Gregory 1970. In: Fuller P. and Neilson M. 2017)

52


CABI (2009) points out the following impacts of Ameiurus nativis: Ecosystem change/ habitat alteration, modification of natural benthic communities, negatively impacts aquaculture/fisheries, negatively impacts tourism, reduced amenity values, reduced native biodiversity and threat to/ loss of native species.

2.16. How important is the impact of the organism on biodiversity (e.g. decline in native species, changes in native species communities, hybridisation) currently in Europe (include any past impact in your response)?

major medium Ameiurus natalis is partially responsible for the decline of the Chiricahua leopard frog (Rana chiricahuensis) in southeastern Arizona (Rosen et al., 1995; Fuller et al., 1999).

Ameiurus nebulosus has negative effects on native fish species by feeding on the bottom fauna, small fishes, fish larvae, and roe (Pujin and Sotirov, 1966).

Of the European countries where Ameiurus melas has been introduced, four of them reported impacts on the ecological community due to dominance, three reported bioaccumulation of pollutants, two reported impacts due to competition (for food or/and for space) with native species, and one reported impacts due to predation on native species. There may also be impacts (direct or indirect) through increased turbidity related to reduced macrophyte growth and reduced stability of substrates (Hubble, 2011).

The bullheads should be considered generalist, foraging on the most abundant and available prey. The impact is because of the competition, due to the coincidences with the preys used by some native species, predation over native species and habitat degradation (Leunda et al, 2008).

53


As compiled in CABI (http://www.cabi.org/isc/), impacts produced by A.melas, A. nebulosus and A. natalis such as competition (for food and/or space) with native species, and predation of native species have been reported. In the same way, A. natalis are adaptive opportunistic and omnivores eaters, consuming whatever is edible within their environment and has a negative impact on native species, decreasing both the abundance and diversity of species in an area (Hughes and Herlihy, 2012).

Ameiurus spp. are normally considered detritivores but recent studies suggest their diet include fish and fish eggs (Boet, 1980). Therefore, this species might be reducing the amount of available prey for native predators. Due to the generalist and opportunistic feeding habits of Ameiurus species, Leunda et al. (2008) analyzed data from Spain and Portugal indicating impacts of A. melas on a wide range of potential prey species as well as impacts through competition. In this study, black bullheads consumed plant material, terrestrial prey and co-occurring fish species (native or exotic), taking the most abundant and available prey. A. nataslis is partially responsible for the decline of the Chiricahua leopard frog (Rana chiricahuensis) in southeastern Arizona (Rosen et al., 1995; Fuller et al., 1999).

Although A. nebulosus is not considered a quarantined pest, several countries Switzerland (Wittenberg, 2005); Poland (FAO, 1997); Chile (Welcomme, 1988)) reported adverse effects on native fish communities following its establishment.

54


Ruiz-Navarro et al. (2014) demonstrated that native fish species play an important role in the diet of A. melas in their invaded range (England), constituting ~30% of food items ingested.

Out of the 37 fish species introduced to Spain, 31 are freshwater species with the greatest potential for ecological impact attributed to black bullhead Ameiurus melas (Rafinesque, 1820) (42 % of all introductions worldwide, n=21) followed by topmouth gudgeon Pseudorasbora parva (Temminck and Schlegel, 1846) (37% of all introductions worldwide, n=35) (Gozlan, 2010).

Due to the generalist and opportunistic feeding habits of this species, Leunda et al. (2008) analysed data from Spain and Portugal indicating impacts on a wide range of potential prey species as well as impacts through competition. In this study, black bullheads consumed plant material, terrestrial prey and co-occurring fish species (native or exotic), taking the most abundant and available prey. Therefore, this species might be reducing the amount of available prey for native predators. Leunda et al (2008) study results suggest that the black bullhead could be negatively affecting native ichthyofauna in two ways. First, the results showed that black bullheads are preying on native fish species such as B. graellsii, P. miegii and G. lozanoi. Even if only fish bony remains (e.g. scales, opercula, cleithra and pharyngeal arches) were identified in black bullhead stomachs, egg predation could not be excluded. Probably, egg predation was not detected because of rapid digestion. Secondly, this study showed that the diet composition of black bullhead is similar to the diet

55


described for some co-occurring Iberian native species. Taking into account black bullhead’s voracity and aggressive behaviour, the diet similarity might lead to an unfavourable competition for the same food resources, subsequently, displacing native fishes to suboptimal food resources.

A. melas can reach populations as high as 227 kg/ha; individuals have been found with large amounts of vegetation in their stomachs (NatureServe 2006).

A. melas in small lakes, for example, on Lasqueti I. This species and pumpkinseeds can extirpate a stickleback population in 2 years (Cannings and Ptolemy 1998). The catfish feeds on the eggs of the stickleback (Backhouse 2000).

The Ameiurus species have similar nutrition habits, eating benthic organisms such as molluscs, immature insects, leeches, crustaceans, worms, algae, plant material, fishes and fish eggs (Scott and Crossman, 1973), so we can affirm that the impact on the environment is important, especially on the native species.

Ameiurus melas

In the Slovak part of the middle Danube, invasive species of fishes, especially two species of gobies (Neogobius melanostomus and Neogobius kessleri), topmouth gudgeon Pseudorasbora parva and black bullhead Ameiurus melas, have become a serious problem for native fish communities. Small benthic native species, e.g. bullhead Cottus gobio, white‐finned gudgeon Gobio albipinnatus and stone loach B.

56


barbatula, virtually disappeared from the local fish communities. The current list of invasive species of fishes in Slovakia contains nine species (A. melas, C. gibelio, pumpkinseed Lepomis gibbosus, monkey goby Neogobius fluviatilis, racer goby Neogobius gymnotrachelus, N. kessleri, N. melanostomus, Amur sleeper Perccottus glenii and P. parva) (Novomeska and Kovac, 2016).

CABI (2015a) remarks on the impact on Gila cypha and Rana chiricahuensis populations. According to Marsh and Douglas (1997), introduced A. melas feed on endangered humpback chub, Gila cypha, in the Little Colorado River (USA) and may exert a negative impact on the population there

Also CABI (2015a) mentions impacts such as competition (for food and/or space) with native species, and predation of native species have been reported. This species is normally considered a detritivore but recent studies suggest its diet could include fish and fish eggs (Boet, 1980). Minckley (1973) reported that A. melas is considered a pest in Arizona as it forms large populations which compete with more desirable fishes for space and food. They are also voracious predators of newly hatched gamefish (Whitmore, 1997). According to Rosen et al. (1995), introduced predatory fishes, including A. melas, are probably partially responsible for the decline of the Chiricahua leopard frog (Rana chiricahuensis) in south-eastern Arizona. Black bullhead may also have an indirect effect by increasing turbidity (Braig and Johnson, 2003), potentially modifying the feeding efficiency of visual predators (Reid et al., 1999; Utne-Palm, 2002). Black bullheads tend to be found in high local abundance, their

57


behaviour could therefore interfere with accompanying species and negatively affect the behavior of native predators and prey. “

The presence of A. melas in a lagoon in Zamora (Spain) is considered the cause ot the decline of Pelodytes punctatus and Discoglossus galganoi (MAGRAMA, 2016).

Black bullhead may therefore affect the native fauna in three distinct ways. First, it may prey directly on some species, therefore reducing the amount of available prey for native predators. Second, black bullhead may have an indirect effect by generating turbidity that can modify the feeding efficiency of visual predators. Third, due to their high local abundance, black bullhead behaviour may interfere with accompanying species and hence negatively affect the behavioural feeding phases of native predators and the anti-predator behaviour of native prey (Kreutzenberger et al., 2008).

These sorts of indirect effects on native freshwater animals have been reported following the introduction of non-native invasive species. For instance, the black bullhead Ameiurus melas Rafinesque, an ictalurid catfish native to North America, has become one of the most successful exotic fish in European freshwater ecosystems. A series of experiments has shown that the presence of this invader reduces the predation success of Esox lucius on minnows, not by actively competing with pike for minnows, but simply by interfering with the normal behaviour of pike. Infection levels by parasites normally transmitted trophically from minnows to pike may be reduced as a consequence. However, since pike switch to other food items, they

58


may be exposed to other parasites transmitted via these different preys (Poulin et al., 2011).

Ameirus nebulosus

CABI (2015b) remarks on the impact on Gasterosteus populations. Brown bullhead are scavengers as well as predators, locating their prey in the substrate through the use of their sensory barbels (Global Invasive Species, 2006).

As an adaptation for prey capture within turbid waters, the species uses oral barbels to sense food items. A. nebulosus is a generalist omnivore, feeding mostly at night and eating benthic organisms that occur frequently within freshwaters: waste, molluscs, immature insects, terrestrial insects, leeches, crustaceans, worms, algae, plant material, fishes and fish eggs. Young (30-60 mm total length) prefer chironomid larvae, ostracods, amphipods, mayflies and other small aquatic invertebrates

Ameiurus nebulosus introductions may lead to competition for food or space and predation on small fishes, invertebrates or other small food items. Of particular concern is the potential for altered energetic pathways within recipient ecosystems, given their omnivorous diet and a body structure that precludes predation from but all of the largest fishes.

As an adaptation for prey capture within turbid waters, the species uses oral barbels to sense food items. A. nebulosus is a generalist omnivore, feeding mostly at night and eating benthic organisms that occur frequently within freshwaters: waste, molluscs, immature insects,

59


terrestrial insects, leeches, crustaceans, worms, algae, plant material, fishes and fish eggs (Scott and Crossman, 1973). Young (30-60 mm total length) prefer chironomid larvae, ostracods, amphipods, mayflies and other small aquatic invertebrates (Scott and Crossman, 1973) (CABI, 2015b).

Feeds on a wide variety of items including snails, freshwater crayfish, fish eggs, worms, insects (adults and larvae), fish and algae. The main prey of adult brown bull head in Lake Taupo, New Zealand are freshwater crayfish (global Invasive Species, 2006).

Nonnative predators, including Brown Bullhead, have been shown to reduce the abundanceand diversity of native prey species in several Pacific Northwest rivers Fuller and Neilson, 2017b).

A. natalis has a negative impact on native species decreasing both the abundance and diversity of species in an area. A. nataslis is partially responsible for the decline of the Chiricahua leopard frog (Rana chiricahuensis) in southeastern Arizona.

Since A. natalis have few predators, are able to survive harsh environmental conditions and have a high reproductive rate they are often the only species in small, shallow lakes and can quickly overpopulate these bodies of water (CABI, 2009).

Impact of Introduction: Introduced predatory fishes, including the Yellow Bullhead, are likely at least partially responsible for the decline of the Chiricahua leopard frog Rana chiricahuensis in southeastern Arizona, and have been shown to reduce the abundance

60


and diversity of native prey species in several PacificNorthwest rivers (Fuller and Neilson, 2017c).

Ameiurus catus is apparently responsible for the disappearance of Sacramento perch Archoplites interruptus in Thurston Lake, California (Fuller and Neilson, 2017d).

2.17. How important is the impact of the organism on biodiversity likely to be in the future in Europe?

major medium The impact that occurs mostly on aquatic ecosystems is very high, so the effect of invasive species such as Ameiurus spp. is one factor more to add on the loss of native biodiversity.Negative impact such as competition (for food and/or space) and predation of native species have been reported to all analyzed species of Ameiurus. (http://www.cabi.org/isc/).Changes in water transparency and increase of turbidity could affect all the ecosystems where Ameiurus spp. are present.

2.18. How important is alteration of ecosystem function (e.g. habitat change, nutrient cycling, trophic interactions), including losses to ecosystem services, caused by the organism currently in Europe (include any past impact in your response)?

major high Of particular concern is the potential for altered energetic pathways within recipient ecosystems, given their omnivorous diet and a body structure that precludes predation from but all of the largest fishes.

They are unpopular, because they form dense stunted populations. Their adaptability and ferocious feeding behaviour make them a grave threat to the native fish and amphibian fauna. In places, they have built up huge populations and replaced native fish species, probably through competition for food (FOEN, 2006).

The loss of species, as well as the transformation of the habitat and modification of its natural conditions, such

61

http://www.cabi.org/isc/


as turbidity increased, supposes an important effect on the function of ecosystems.

Impact on fishing as a cultural ecosystem service is demonstrated: A fishery in North London succumbed to this highly efficient invader, and the local angling club had lost one of their best fisheries.

As included in the “Ecological risk assessment of non-indigenous species in Lake Balaton: a pilot study” (http://eulakes-model.eu/media/files/ecological-risk-assessment-of-non-indigenous-species-in-lake-balaton.pdf) the FISK assessments were undertaken independently by the three co-authors. Each person calculated the total FISK scores for each species. Altogether nine species (Carassius gibelio; Perccottus glenii; Anguilla anguilla; Lepomis gibbosus; Neogobius fluviatilis; Gambusia holbrooki; Hypophthalmichtys molitrix x nobilis; Ameiurus melas; Pseudorasbora parva). 5 of the 9 examined fish species (55.6%) – among of them Ameiurus melas- received FISK scores ≥19 (scores between 24 and 33), and thus could be classified as species posing high risk to become abundant in the Balaton catchment. For 6 species (among of them Ameiurus melas), effect on the Catchments seemed to be more significant, which could mean the hardly quantifiable costs of ecosystem services (Farber et al., 2002).

In France the results from Cucherousset et al. (2006) study suggest that the invasion of A. melas has been facilitated by the expansion of reed beds associated with the diminution of agricultural pressure in recent decades. This study represents an unusual example where human activities can have had an unexpected

62





effect by facilitating an invasive fish species. Furthermore, A. melas abundance increases when decreasing water depth (Brown et al. 1999) and the production of a large amount of litter by the reed beds might favour A. melas by limiting water depth.

This study examined the distribution and habitat selection of the invasive black bullhead in the ditches and surrounded temporary flooded habitats of an artificial wetland in western France. A multiscale approach was used to quantify patterns of A.melas abundance in relation to physical habitat characteristics in the ditch network. Young-of-the-year (YOY) and adult A. melas largely dominated the local fish assemblage but were highly variable among sites. Although we found evidence for some fine-scale habitat differences for YOY and adult individuals, the abundance of A. melas was positively and consistently related to the dominance of reed beds. Furthermore, A. melas preferentially used reed beds as opposed to marsh meadows during the flooding period. The results from this study suggest that the invasion of A. melas has been facilitated by the expansion of reed beds associated with the diminution of agricultural pressure in recent decades. This study represents an unusual example where human activities can have had an unexpected effect by facilitating an invasive fish species (Cucherousset et al., 2006).

Ameiurus melas is related to the physic-chemical dimension of water quality. Changes in water transparency and increase of turbidity (Braig and Johnson, 2003).

63


Ameiurus species are responsible for the muddying of the water in their search for food which may alter ecosystems and stop other species to feed.

Ameiurus melas

Of the countries where it has been introduced in Europe there may be impacts on habitat (direct or indirect), potentially through increased turbidity related to reduced macrophyte growth and reduced stability of substrates (CABI, 2015).

Black bullhead may also have an indirect effect by increasing turbidity (Braig and Johnson, 2003), potentially modifying the feeding efficiency of visual predators (Reid et al., 1999; Utne-Palm, 2002).

The greater impact of benthivorous fish on turbidity within shallow systems may be an indirect one through the destruction of macrophytes and subsequent destabilization of unconsolidated substrates (Braig et al, 2003)

Ameiurus nebulosus

A. nebulosus may increase physical disturbance within freshwaters due to their benthivorous feeding habits. Although their barbels may aid in prey capture, foraging aggressively within substrates may be necessary to dislodge certain benthic prey items, which in-turn can increase turbidity and lead to altered productivity and nutrient cycling. Estimates regarding habitat impacts following A. nebulosus introductions have not been quantified (CABI, 2015).

64


Ameiurus natalis

A. natalis are responsible for the muddying of the water in their search for food which may alter ecosystems. It has been suggested that this action makes it difficult for visual predators such as centrarchids to find food.

2.19. How important is alteration of ecosystem function (e.g. habitat change, nutrient cycling, trophic interactions), including losses to ecosystem services, caused by the organism likely to be in Europe in the future?

major high Negative effects on aquatic ecosystems are intensifying as they are suffering transformations by which worsens its evolution in the future.

Both surface and bottom turbidity increased with adult and juvenile black bullhead biomass (Braig and Johnson, 2003). This has been demonstrated to have an impact on the foraging success of native predators, such as the pike Esox lucius (Kreutzenberger et al., 2008)

The Guadalquivir Estuary (Spain) is a highly productive ecosystem that provides permanent habitats for estuarine species as well as playing an important role as breeding and adult-feeding grounds for marine species (Baldó and Drake 2002; González-Gordillo and Rodríguez 2003). Considering the current increase of the A. melas population and its ability to feed voraciously on a variety of prey from small aquatic macroinvertebrates to fish (Leunda et al. 2008), further impacts on estuarine ecosystem function and services may occur but this requires further study (Garcia-de-Lomas et al., 2009).

As described in Vandekerkhove et al. (2013) there is increasing evidence that IAS can adversely affect the structure and functioning of aquatic ecosystems (Kideys, 2002; Krisp and Maier, 2005; Klein and Verlaque, 2008). Alternatively, a change in structure

65


and functioning may also facilitate the introduction and spread of alien species. A reduction in native species richness – for example, caused by hydromorphological changes – may affect the resilience of communities to invasions (Dunstan and Johnson 2006), or eutrophication may dramatically alter the food-web structure in favour of non-native species. The latter is true for many shallow lakes, where increased nutrient levels have induced a shift from a top-down to a bottom-up regulated food web structure, with reduced control of invasive planktivorous and benthivorous fish (Scheffer 1998). The effects of IAS and other pressures are likely to reinforce each other, potentially resulting in an invasional meltdown at the water body level (Ricciardi 2001). At the regional scale, positive feedback mechanisms might explain the observed exponential increase in the numbers of alien species (DAISIE 2009).

2.20. How important is decline in conservation status (e.g. sites of nature conservation value, WFD classification) caused by the organism currently in Europe?

major high Ameiurus melas is found in areas of high value for the conservation of nature, so the loss of biodiversity supposes a high decline in the conservation status of these areas.

In Spain, this species is present in the National Park Tablas de Daimiel (http://www.castillalamancha.es/sites/default/files/documentos/paginas/archivos/doc_1_es0000013_0.pdf). Its reproduction is also confirmed in the Doñana Natural Area.

In France the species is included in the list of Fish species recorded on the Natura 2000 site of the Lower Valley Doubs - Doubs and Clauge.

2.21. How important is decline in conservation status (e.g. major high The loss of biodiversity and quality of the ecosystems

66

http://www.castillalamancha.es/sites/default/files/documentos/paginas/archivos/doc_1_es0000013_0.pdf



sites of nature conservation value, WFD classification) caused by the organism likely to be in the future in Europe?

supposes a decline of the nature conservation value which will be worse in the future in these areas.

67


Responses of the Index of Community Integrity quality classes detailed in the table to different indicators of water quality, physical habitat and biotic perturbations. IBMWP (Alba-Tercedor et al., 2002) measures water quality, QBR Munné et al. (2003) evaluates the perturbation status of the riparian area. The responses to the invasion status (measured as the proportion of invasive species richness and abundance) are also shown (Hermoso et al, 2010).

2.22. How important is it that genetic traits of the organism could be carried to other species, modifying their genetic nature and making their economic, environmental or social effects more serious?

minimal medium There is no evidence of possibility of hybridisation with native species. I. punctatus (channel catfish) have been known to mate with brown bullhead (Ameiurus nebulosus), yellow bullhead (Ameiurus natalis), and black bullhead (Ameiurus melas), resulting in a variety of hybrid catfish (Florida Museum of Natural History. Online: https://www.flmnh.ufl.edu/fish/discover/species-profiles/ictalurus-punctatus/)

Introgressive hybridization among A. nebulosus and A. melas may difficult in its differentiation and, furthermore, its control. Hybridization of A. natalis with A. melas and A. nebulosus is rare.

Hybridization between brown bullhead and black bullhead may occur where the species frequently co-occur. No other hybrids are known within North America. A. nebulosus has been sequenced (CABI, 2015a, 2015b)

A. natalis has a diploid (2n) chromosome number of 62 and haploid/gametic number of 31. Hybridization with A. melas and A. nebulosus is rare (CABI, 2009).

68


2.23. How important is social, human health or other harm (not directly included in economic and environmental categories) caused by the organism within its existing geographic range?

minimal medium No effects known (Wiesner et al. 2010).

Black bullheads can cause a painful sting if pectoral spines puncture human flesh. Black bullheads contain small amounts of venom at the ends of spine which can cause pain for up to a week. ("A Boundary Waters Compendium", 2004; Etnier and Starnes, 1993).

A painful wound can be inflicted by the sharp spines in the fins of brown bullhead catfish if they are not handled carefully. Toxins released by the fish contribute to the pain of the wound (Global Invasive Species, 2006).

2.24. How important is the impact of the organism as food, a host, a symbiont or a vector for other damaging organisms (e.g. diseases)?

moderate low Transmission of pathogens could likely be a risk but, currently, it is not enough documented.

Ameiurus melas host Flavobacterium columnare and Edwardsiolla ictaluri. Diseases of Concern: Epizootic ulcerative syndrome (Aphanomyces invadans) - Susceptible Species of Aquatic Animals listed in Schedule III of Canada’s Health of Animals Regulations – shows high susceptibility to ECV infection. Furthermore a significant mortality associated with the typical signs of systemic viral infections was observed in groups challenge with epizootic haematopoietic necrosis virus (EHNV) (Gobbo et al., 2010). Ranaviruses pose a potential threat to fishs and amphibians. Has also been shown to host Ancyrocephalus pricei in a UK population (Sheath et al., 2015).

Epizootic haematopoietic necrosis was observed in 0+ and 1+ old black bullhead reared in polyculture with carp. The disease induced mortality of 6 tons of this species over a one-month period (from mid-August to

69

http://animaldiversity.org/accounts/Ameiurus_melas/#d835b80ee82cccd35d799c808c7d2826

http://animaldiversity.org/accounts/Ameiurus_melas/#acdbc7b2d81de0c28bd9eaccb35efd8f

http://animaldiversity.org/accounts/Ameiurus_melas/#acdbc7b2d81de0c28bd9eaccb35efd8f


mid-September), whereas no mortality in carp was recorded at the time nor any sign of the disease in 1+ old carp reared in the same pond (Jeremic and Radosavljevic, 2009).

A. natalis is known to be a host species for creepers (Strophitus undulatus) and are also parasitized by leeches (Hirudinea) (Gray et al., 2001). They are known to host the larval stage (glochidia) of the clam Anodonta grandis [Pyganodon grandis] (Hart and Fuller, 1974).A study of parasites of A. natalis in Texas by Mayberry et al. (2000) found the following: Cestoda: Proteoceph-alidae, Proteocephalus ambloplitis; Trematoda: Allo-glossidium kenti, Cleidodiscus pricei, Phyllodistomum caudatum, Posthodiplostomum minimum, Gyrodactylus; Nemata: Spinectus carolini [Spinitectus car-olini], Spinectus microcantus [Spinitectus mi-crocanthus], Spyroxis contorta.

Scott and Crossman (1973) describe the following para-sites known from within the species, which have the po-tential to infect recipient fish communities following A. nebulosus introductions: Protozoa, Trematoda, Cestoda, Nematoda, Acanthocephala, leeches, Mollusca, and Crustacea. (http://www.cabi.org/isc/datasheet/94468).In Italy, the introduction of the exotic cestode Corallobothrium parafimbriatum Befus et Freeman, 1973 with A. melas was recorded. The further spreading of the cestode with its fish host to other countries was not recorded. Acanthocephalus anguillae, adopted by black bullhead, is the common parasite of native fishes (about 40 species) in Slovakia (Košuthová et al., 2009).

2.25. How important might other impacts not already NA

70

http://www.cabi.org/isc/datasheet/94468


covered by previous questions be resulting from introduction of the organism? (specify in the comment box)

2.26. How important are the expected impacts of the organism despite any natural control by other organisms, such as predators, parasites or pathogens that may already be present in Europe?

major medium It is not well know how predators, parasites or pathogens could affect the species. At least in Spain the only possible fish predators will be also exotic. Native species are usually smaller (70% of then endemic) and with small mouths which make them bad competitors.

Although A. nebulosus are predated upon by larger fishes, the likelihood of long-distance dispersal resulting from this vector is low. Most piscivorous fishes are unable to utilize A. nebulosus for food due to their sharp, strong dorsal and pectoral spines that may lock into an erect position when predated upon (CABI, 2015b).

Ameiurus melas have large sharp spines on both their dorsal and pectoral fins; when attacked they straighten them making them difficult to swallow and as such very few predators are able to consume them. This species also produces a mild poison that runs down the spines and into the wound. These spines combined with the species' nocturnal feeding regime make black bullheads an uncommon prey item for other fish species. Small-mouth bass (Micropterus dolomieu), largemouth bass (Micropterus salmoides), herons as well as some turtle species occasionally consume the young and small adults, with their main predator being humans. (CABI, 2015a)

Ameiurus nebulosus. By virtue of its strong pectoral and dorsal spines, the adult A. nebulosus is well protected from predation by all but the largest fish predators in

71


their native range in Canada. Although present in juven-iles, the spines are less robust making juveniles more susceptible to predation by fishes with a wider range in size. Within its native range, predators include members of the pike family (Esox spp.) and pike perches (Sander spp.). Where introduced on the Gulf Islands of British Columbia in Canada, there are no other piscivorous fishes present and, hence, no native predators to intro-duced A. nebulosus (CABI, 2015b).

Ameiurus natalis Several natural enemies of A. natalis have been reported in its native range; however, by virtue of their strong pectoral and dorsal spines, adults are well protected from predation by all but the largest fish predators Members of the pike family (Esox species), walleye (Sander vitreus), large wading birds and some turtles may feed on adults.Juvenile spines are less robust making them more sus-ceptible to predation by fishes with a wider range in size. Within its native range, predators of juveniles in-clude Micropterus salmoides, M. dolomieu, Sander canadensis, species of Ambloplites and Pomoxis includ-ing Pomoxis nigromaculatus and other catfish as well as aquatic invertebrates, leeches and crayfish. The eggs and small fry are predated by Lepomis macrochirus and other species of Lepomis (CABI, 2009).

2.27. Indicate any parts of Europe where economic, environmental and social impacts are particularly likely to occur (provide as much detail as possible).

[In all rivers, reservoirs, dams, lakes, lagoons and ponds]

medium Negative impacts could occur in all the distribution area where it is established.

Particularly National Parks, areas of high value for the conservation of nature are more susceptible to suffer

72


high economic, environmental and social negative impacts.

In Spain, the National Park Tablas de Daimiel (http://www.castillalamancha.es/sites/default/files/documentos/paginas/archivos/doc_1_es0000013_0.pdf). and the Doñana Natural Area are two important conservation areas that suffers because of the reproduction of Ameiurus melas in their waters

In France the species is included in the list of Fish species recorded on the Natura 2000 site of the Lower Valley Doubs - Doubs and Clauge.

Ameiurus melas There is potential for the black bullhead to cause a negative social impact as it can be a 'nuisance' species taking lines/bait intended for other species, because of this anglers not targeting this species might move on to black bullhead free waters (CABI, 2015a).

Ameiurus nebulosus populations may hinder local native sport fisheries by out-competing target fishes, resulting in reduced angling opportunities and their social impacts. Alternatively, introductions may be encouraged locally if A. nebulosus are favoured for sport. Introduction into previously fishless waters may provide new or valued angling opportunities. Current estimates of social impacts resulting from introductions have not been documented (CABI, 2015b).

73




RISK SUMMARIES

RESPONSE CONFIDENCE COMMENTSummarise Entry Moderately high At least four of the total of seven species of Ameiurus

genus are already present in Europe, (24 of the total of 28 European countries have recorded at least one Ameiurus sp). In the meantime the interest of this species for fishing has been reduced lately, and some countries have forbidden new entries of A. melas and A. neboulosus (France, Poland, etc.).

Summarise Establishment very likely high At least one Ameiurus sp. (A. melas) is established in France, Germany, Austria, Italy, Portugal, Spain, the Netherlands, Belgium, Czech Republic, Croatia, Ro-mania, Finland, Hungary, Slovakia, Slovenia, Bulgaria, Greece, Croatia, Ireland, Romania, Poland, Sweden, Denmark, Estonia and the United Kingdom. A. nebu-losus has been cited as established in many countries, although it seems to be A. melas in most cases. A. melas and A. nebulosus would probably adapt easily to the cli-matic conditions in Malta and Cyprus and possible in Lithuania and Latvia.

This demersal species inhabits low-flowing habitats (limnophilic) with soft substrata in all riverine and la-custrine environments, including artificial ones such as ponds and reservoirs.

Summarise Spread moderately medium The expansion depends on ecological conditions of river basins in which it is introduced, but if it finds suitable conditions, it can be easy for these successful invaders to spread. A reduction in native species richness – for example, caused by hydromorphological changes or anthropogenic influences – may affect the resilience of communities to invasions (Dunstan and

74


Johnson, 2006), or eutrophication may dramatically alter the food-web structure in favour of non-native species.

This means that Ameiurus spp. could spread easily to other ecosystems.

Flexible life-history traits and wide environmental tolerances facilitate Ameiurus spp. establishment and dispersal.

Summarise Impact major medium Ameiurus spp. is generalist, foraging on the most abundant and available prey. The impact is because of the competition, due to the coincidences with the preys used by some native species, direct predation of native species and habitat degradation.

Impacts in water quality, such as increased turbidity, have also been demonstrated.

Conclusion of the risk assessment major medium The release and translocation of specimens by fishermen and pet-owners and the easy adaptability to the natural conditions in the lakes and rivers from Europe, makes possible its continuous expansion transforming aquatic ecosystems and causing the disappearance of native species, mainly fish.

Aquatic habitats are one of the habitats more threatened by invasive alien species (IAS). At present IAS are one of the most important direct drivers of biodiversity loss throughout the world and constitute the greatest threat to fragile ecosystems such as small isolated water bodies.

ADDITIONAL QUESTIONS - CLIMATE CHANGE3.1. What aspects of climate change, if any, are most [Temperature medium The effects of climate change in the progressive

75


likely to affect the risk assessment for this organism? ; rain] warming of water, even in temporary drying up of rivers, during which this species is able to stay buried in the mud, would favour its population increase, which would be a major impact on native species.Species composition, diversity, global abundance and size structure of fish communities exhibited important trends related to water warming in large rivers (http://www.firf.fr/team/martin/1fichiers/1pdf/DaufresneGCB2007.pdf).Cucherousset et al. (2007) studied fish emigration patterns from four temporary wetlands exposed to drought from May to August 2004 in the Brière Marsh (France). Emigration timing was highly correlated with published physiological tolerance levels for these species, demonstrating a tight linkage between water quality and emigration patterns. Two non-native species (A. melas and G. holbrooki) showed the latest emigration from the temporary habitats, reflecting a high level of tolerance to drought conditions that may contribute to their success as wetland invaders (Cucherousset et al, 2007).

The greater hydrological variability predicted to accompany the warmer climatic conditions is expected to increase fish dispersal, so wider establishment of non-native fishes is likely to enhance the risks of adverse consequences for native species and ecosystems (Coop et al, 2004). However, existing evidence for adverse impacts remains equivocal or lacking for many nonnative fishes

3.2. What is the likely timeframe for such changes? 40 years low Aquatic environments are particularly affected by climate change.

3.3. What aspects of the risk assessment are most likely to change as a result of climate change?

[Increase suitability of the habitat for

medium The water temperature could also explain the change in habitat use and searching behaviour by bullheads. In the wild, bullheads and crappies would compensate for the

76


the species] increased water temperature by finding areas that contain cool water temperatures, allowing their body temperature to cool as a result. (Walberg, 2011). This could result in a natural spread in colder waters such as Latvia´s and Lithuania´s ones, where Ameiurus spp seem not to be recorded yet.

Additionally, where A. melas is present in more temperate climates (UK for example), increased water temperatures as a result of climate change could extend the period for successful spawning and increase foraging efficacy (Environment Agency- UK, unpublished data).

ADDITIONAL QUESTIONS - RESEARCH4.1. If there is any research that would significantly strengthen confidence in the risk assessment please summarise this here.

[The impact to native fauna should be further investigated]

medium Confidence in the risk assessment is high for establishment, spread and damage in aquatic ecosystems. Data on the possible impacts on native species, principally on endemic fishes, are needed. Further studies are required to assess these impacts. It would be very important to increase the management actions to protect them.

Research into the efficacy of bio-control and bio-manipulation of A. melas populations should be investigated (cf. Davies and Britton, 2015), to provide additional control measures to those already available (See Comment 1.21).

Further investigation is needed to assess Ameiurus population trends and impacts, such as decline of reservoir water quality and food web structure alteration.

77


Further cost data are also needed.

78


REFERENCES:

Almeida D., Ribeiro F., Leunda P.M., Vilizzi L., Copp G.H. (2013). Effectiveness of FISK, an invasiveness screening tool for non-native freshwater fishes, to perform risk identification assessments in the Iberian Peninsula. Risk Anal. 2013 Aug ;33(8):1404-13. doi: 10.1111/risa.12050. Epub 2013 Apr 24.

Amori G., Angelici F.M., Frugis S., Gandolfi G., Groppali R., Lanza B., Relini G. and Vicini G. (1993). Vertebrata. In A. Minelli, S. Ruffo and S. La Posta (eds.) Checklist delle specie della fauna Italiana, 110. Calderini, Bologna, 83 p.

Anseeuw D., Branquart E., Lieffrig F., Louette G., Micha J.-C., Parkinson D., Verreycken H. (2011). Harmonia database: Ameiurus nebulosus. Harmonia version 1.2, Belgian Forum on Invasive Species, accessed on 25 of November 2016 from: http://ias.biodiversity.be Invasive species in Belgium

Arce-H.M., Lundberg J.G., O'Leary M.A. (2016). Phylogeny of the North American catfish family Ictaluridae (Teleostei: Siluriformes) combining morphology, genes and fossils. Cladistics (2016) 1–23.

Backhouse F. (2000). Extinct and extirpated species. B.C. Ministry of Environment, Lands and Parks, Wildlife Branch, Victoria, B.C. 6 p. Barbieri R., S. Zogaris, E. Kalogianni, M. Th. Stoumboudi, Y. Chatzinikolaou, S. Giakoumi, Y. Kapakos, D. Kommatas, N. Koutsikos, V. Tachos, L.

Vardakas and Economou A.N. (2015). Freshwater Fishes and Lampreys of Greece: An annotated checklist. Monographs on Marine Sciences No. 8. Hellenic Centre for Marine Research: Athens, Greece. p. 130.

Bartley D.M. (2006). Introduced species in fisheries and aquaculture: information for responsible use and control . Rome, Italy, FAO: unpaginated. Bianco P.G. and Ketmaier V. (2016). Nature and status of freshwater and estuarine fisheries in Italy and Western Balkans. In Craig JF Ed. Freshwater

Fisheries Ecology (pp 283-291). West Sussex. UK. Bódis E., Borza P., Potyó I., Puky M., Weiperth A. and Guti G., (2012). Invasive mollusc, crustacean, fish and reptile species along the Hungarian

stretch of the river Danube and some connected waters. Acta Zool. Acad. Sci. Hung., 58 (Suppl.), 29–45. Boët P. (1980). L’alimentation du poisson-chat (Ictalurus melas Raf.) dans le lac de Créteil. Annales de Limnologie 16: 255– 270. Braig E.C., Johnson D.L. (2003). Impact of black bullhead (Ameiurus melas) on turbidity in a diked wetland, Hydrobiologia, 490: 11–21. Branquart E. (Ed.). (2011). Alert, black and watch lists of invasive species in Belgium. Harmonia version 1.2, Belgian Forum on Invasive species,

accessed on <13 + 11+ 2016> from: http://ias.biodiversity.be. Britton J. R., Davies G. D. (2006). First record of the white catfish Ameiurus catus in Great Britain. Journal of Fish Biology, 69: 1236–1238. Britton J.R., Brazier M. (2006). Eradicating the invasive topmouth gudgeon, Pseudorasbora parva, from a recreational fishery in northern England.

Fisheries Management and Ecology, 13: 329–335. Britton J.R., Cucherousset J., Davies G.D., Godard M.J. and Copp G.H. (2010). Non-native fishes and climate change: predicting species responses to

warming temperatures in a temperate region. Freshwater Biology 55, 1130–1141. Brylinski E. and Chybowski Ł. (2000). Sumik karłowaty Ictalurus nebulosus (Le Sueur, 1819). In Ryby słodkowodne Polski (Brylinska, M., ed.), pp.

354–356. Warszawa: PWN.

79

http://www.cabi.org/isc/abstract/20067205158


CABI. 2009. Ameiurus natalis (yellow bullhead). Invasive Species Compendium. [ONLINE] Available at: http://www.cabi.org/isc/datasheet/94467. [Accessed 20 January 2017].

CABI. 2015a. Ameiurus melas (black bullhead). Invasive Species Compendium. [ONLINE] Available at: http://www.cabi.org/isc/datasheet/94466. [Accessed 20 January 2017].

CABI. 2015b. Ameiurus nebulosus (brown bullhead). Invasive Species Compendium. [ONLINE] Available at: http://www.cabi.org/isc/datasheet/94468. [Accessed 20 January 2017].

Ćaleta M., Jelic D., Buj I., Zanella D., Marcic Z., Mustafic P. and Mrakovcic M. (2011). First record of the invasive species rotan (Perccottus glenii Dybowski 1877) in Croatia. Journal of Applied Ichthyology, 27 (1): 146-147.

Cannings S.G. and J. Ptolemy. (1998). Rare freshwater fish of British Columbia. B.C. Ministry of Environment, Lands and Parks, Victoria, B.C. 214 p.

Collier KJ and Grainger NPJ (eds) (2015). New Zealand Invasive Fish Management Handbook. Lake Ecosystem Restoration New Zealand (LERNZ; The University of Waikato) and Department of Conservation, Hamilton, New Zealand. 212 p.

Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO). Downloaded [11 of November 2016] from: <http://www.conabio.gob.mx/conocimiento/bioseguridad/doctos/bioseguridad.html>

Copp G. H.; Fox M. G.; Masson G.; Fobert E.; Tarkan A. S. (2014). Predicting the Invasiveness of Introduced Freshwater Fishes under Conditions of Climate Warming Using a Life-History Model. 8th International Conference on Biological Invasions from understanding to action. Antalya-TURKEY, 03-08 November

Copp G.H. (1989). The habitat diversity and fish reproductive function of floodplain ecosystems. Environ Biol Fish 26:1–26. Copp G.H., Bianco P.G., Bogutskaya N., Erős T., Falka I., Ferreira M.T., Fox M.G., Freyhof J., Gozlan R.E., Grabowska J., Kováč V., Moreno-

Amich R., Naseka A.M., Peňáz M., Povž M., Przybylski M., Robillard M., Russell I.C., Stakėnas S., Šumer S., Vila-Gispert A., Wiesner C. (2005a). To be, or not to be, a non-native freshwater fish? J Appl Ichthyol 21:242–262

Copp G.H., Tarkan, A.S., Masson, G. et al. (2016). A review of growth and life-history traits of native and non-native European populations of black bullhead Ameiurus melas. Reviews in Fish Biology and Fisheries. Volume 26, Issue 3 , pp 441–469.

Copp GH, Vilizzi L, Mumford J, Fenwick GV, Godard MJ, Gozlan RE (2009) Calibration of FISK, an invasive-ness screening tool for non-native freshwater fishes. Risk Anal 29:457–467

Cucherousset J., Paillisson J.-M., Carpentier A. and Chapman L. J. (2007). Fish emigration from temporary wetlands during drought: the role of physiological tolerance. Fundamental and Applied Limnology Vol.168/2: 169–178

Cucherousset J., Paillisson J. M., Carpentier A., Eybert M. C., Olden, J.D. (2006): Habitat use of an artificial wetland by the invasive catfish Ameiurus melas, Ecology of Freshwater Fish, 15: 589–596.

Cvijanović G., Lenhardt M., Hegediš A., Gačić Z. and Jarić I. Ameiurus melas (Rafinesque) – pest or possibility. Proceedings of the EIFAC Symposium on interations between social, economic and ecological objectives of inland commercial and recreational fisheries and aquaculture. Antalya, Turkey, 21-24 May 2008.

Dana E.D., Barragán JA, García-de-Lomas J, Sánchez-Pino P. (2016). El pez gato negro (Ameiurus melas Rafinisque, 1820) llega al Paraje Natural del Brazo del Este y a la Reserva Natural Concertada de la Dehesa de Abajo (Sevilla, sur de España). Rev. Soc. Gad. Hist. Nat. 10: 1-3

80

http://link.springer.com/journal/11160/26/3/page/1

http://link.springer.com/journal/11160

http://www.conabio.gob.mx/conocimiento/bioseguridad/doctos/bioseguridad.html


Davies G. D. and Britton J. R. (2015). Assessing the efficacy and ecology of biocontrol and biomanipulation for managing invasive pest fish. Journal of Applied Ecology. 52, 1264-1273.

De Miguel R.J., Oliva-Paterna F.J., Glávez-Bravo L., Fernández-Delgado C. (2014). Fish composition in the Guadiamar River basin after one of the worst mining spills in Europe. Limnetica 33:375–383

Dextrase A.K., Mandrak N.E. (2006) Impacts of alien invasive species on freshwater fauna at risk in Canada. Biol Invasions 8:13–14. Dunstan, P. K., and Johnson, C. R. (2006). Linking richness, community variability, and invasion resistance with patch size. Ecology, 87(11), 2842-

2850. EFSA Journal. (2011). Suggested citation: European Food Safety Authority; Report of the Technical Hearing Meeting on Epizootic Ulcerative

Syndrome (EUS). EFSA Journal 2011; 9(10):195. [16 pp.] doi:10.2903/j.efsa.2011.195. Available online: www.efsa.europa.eu/efsajournal Elvira B. (2001). Identification of non-native freshwater fishes established in Europe and assessment of their potential threats to the biological

diversity. Presented at Convention on the conservation of European wildlife and natural habitats, 21st meeting, Strasbourg. Elvira B., (1984). First record of the North American catfish Ictalurus melas (Rafinesque, 1820) (Pisces, Ictaluridae) in Spanish waters. Cybium, 8,

96–98. Elvira B. and Almodóvar A. (2001). Freshwater fish introductions in Spain: facts and figures at the beginning of the 21st century. Journal of Fish

Biology. Volume 59, Issue Supplement sA, pages 323–331 Erdsman D.S. (1984). Exotic fishes in Puerto Rico. Pages 162-176 in Courtenay, W.R., Jr., and J.R. Stauffer, Jr, eds. Distribution, biology, and

management of exotic fishes. John Hopkins University Press. Baltimore, MD. Etnier D. and Starnes W. (1993). The Fishes of Tennessee. The University of Tennessee Press/ Knoxville. FAO. (1997). FAO Database on Introduced Aquatic Species. FAO, Rome, Italy: Food and Agricultural Organization of the United Nations. Federal Office for the Environment FOEN. (2006). Invasive alien species in Switzerland. An inventory of alien species and their threat to

biodiversity and economy in Switzerland. Pp. 155 Ferincz A., Staszny A., Weiperth A., Takács P., Urbányi B., Vilizzi L., Paulovits G., Copp G. (2016). Risk assessment of non-native fishes in the

catchment of the largest Central-European shallow lake (Lake Balaton, Hungary). Hydrobiologia 780(1): 85–97 Froese R. and Pauly D. (2004). FishBase DVD. Penang, Malaysia: Worldfish Center. Online at www.fishbase.org. Froese R. and Pauly D. Editors. (2016). FishBase. World Wide Web electronic publication. www.fishbase.org, version (10/2016). Fuller P. and Neilson M. (2016). Ameiurus catus. USGS Nonindigenous Aquatic Species Database, Gainesville, FL.

https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=729 Revision Date: 2/7/2014. Fuller P. and Neilson M. (2017a). Ameiurus melas. USGS Nonindigenous Aquatic Species Database, Gainesville, FL.

https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=730 Revision Date: 5/29/2012. Fuller P. and Neilson M. (2017b). Ameiurus nebulosus. USGS Nonindigenous Aquatic Species Database, Gainesville, FL.

https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=734 Revision Date: 5/29/2012. Fuller P. and Neilson M. (2017c). Ameiurus natalis. USGS Nonindigenous Aquatic Species Database, Gainesville, FL.

https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=733 Revision Date: 5/29/2012. Fuller P.L., Nico L.G. and Williams J.D. (1999). Non-indigenous fishes introduced into inland water of the United States. American Fisheries Society

Special Publication, 27:613.

81

http://onlinelibrary.wiley.com/doi/10.1111/jfb.2001.59.issue-sA/issuetoc


Gallardo B. and Aldridge D.C. (2013). The ‘dirty dozen’: socio-economic factors amplify the invasion potential of 12 high-risk aquatic invasive species in Great Britain and Ireland. J Appl Ecol, 50: 757–766. doi:10.1111/1365-2664.12079.

Gandolfi G., Zerunian S., Torricelli P. and Marconato A. (eds.). (1991). I pesci delle acque interne italiane [Fishes of Italia]. Ministero dell’Ambiente e Unione Zoologica Italiana, Instituto Poligrafico e Zecca dello Stato, Roma. 1991.

Gante H.F. and Santos C.D.(2002). First records of North American catfish Ictalurus melas (Rafinesque, 1820) in Portugal. J. Fish Biol., 61, 1643–1646.

Garcia-de-Lomas J., Dana E., López-Santiago J., González R., Ceballos G. and Ortega F. (2009). First record of the North American black bullhead Ameiurus melas (Rafinesque, 1820) in the Guadalquivir Estuary (Southern Spain). Aquatic Invasions 4: 719–723, doi:10.3391/ai.2009.4.4.23

Gaviloaie I.C. and Falka I. (2006). Romanian researches on species Ictalurus nebulosus (Le Sueur, 1819)(Pisces, Ictaluridae). Brukenthal Acta Musei 1(3):153–156

GB Non-native species secretariat. (2016). Online: http://www.nonnativespecies.org/factsheet/factsheet.cfm?speciesId=179 Global Invasive Species. (2016). Species profile: Ameiurus nebulosus. Downloaded from

http://www.iucngisd.org/gisd/speciesname/Ameiurus+nebulosus on 26-10-2016. Gobbo F., Cappellozza E., Pastore M.R. and Bovo G. (2010) Susceptibility of black bullhead Ameiurus melas to a panel of ranaviruses. Dis Aquat

Org.Vol 90:167-174. Gozlan R. (2010). The cost of non-native aquatic species introductions in Spain: fact or fiction? Aquatic Invasions. Volume 5, Issue 3: 231-238 Grabowska, J., Kotusz, J., and Witkowski, A. (2010). Alien invasive fish species in Polish waters: an overview. Folia Zoologica, 59(1), 73. Hanchin P.A., Willis D.W. and Hubers M.J. (2002). Black bullhead growth in South Dakota Waters: limnological and community influences. J

Freshw Ecol 17:65–73 Hanel L., Plesnik J., Andreska J., Lusk S., Novak J. and Prisil J. (2011). Alien Fisjes in European waters. Bulletin Lampetra VII: 148-185. Hanke G.F., McNall M.C.E. and Roberts J. (2006). First records of the yellow bullhead, Ameiurus natalis, a loricariid catfish, Panaque suttonorum,

and a silver pacu, Piaractus cf. brachypomus, in British Columbia. Canadian Field-Naturalist, 120(4):421-427. Harka Á. (1997). Terjed vizeinkben a fekete törpeharcsa, Halászat, 90 (3), 109-110. Hartvich P. and Lusk S. (2006). První nález sumečka černého (Ameiurus melas) na Třeboňsku v České republice“ [The first record of the black

bullhead (Ameiurus melas) in the Třeboň district, Czech Republic]. Biodiverzita ichtyofauny ČR, 6: 55 – 58 Hermoso V., Clavero M., Blanco-Garrido F. and Prenda J. (2010). Assessing the ecological status in species-poor systems: A fish-based index for

Mediterranean Rivers (Guadiana River, SW Spain) Ecological Indicators. Volume 10, Issue 6, November, Pages 1152–1161. Holčík J. (1991). Fish introductions in Europe with particular reference to its central and eastern part. Canadian Journal of Fisheries and Aquatic

Sciences, 48, Supplementum 1: 13–23.http://www.wnrmag.com/stories/1998/oct98/bull.htm

Hubble, D. (2011). NNSS, GB Non-native species secretariat. Black Bullhead, Ameiurus melas. Online at http://www.nonnativespecies.org/factsheet/factsheet.cfm?speciesId=179.

Hughes RM, Herlihy AT, (2012). Patterns in catch per unit effort of native prey fish and alien piscivorous fish in 7 Pacific Northwest USA rivers. Fisheries (Bethesda), 37(5):201-211.

82



http://www.nonnativespecies.org/factsheet/factsheet.cfm?speciesId=179

http://www.wnrmag.com/stories/1998/oct98/bull.htm

http://www.sciencedirect.com/science/journal/1470160X/10/6

http://www.sciencedirect.com/science/journal/1470160X

http://www.sciencedirect.com/science/article/pii/S1470160X10000609





Hunnicutt D.W., Cingolani J. and Voss M.A. (2005). Use of mtDNA to Identify Genetic Introgression among Related Species of Catfish. Journal of Great Lakes Research 31(4): 482–491

Integrated Taxonomic Information System on-line database, http://www.itis.gov Invasive Species Specialist Group (ISSG). (2009). ISSG database on global invasive species. Auckland, New Zealand: Invasive Species Specialist

Group and IUCN Species Survival Commission. http://www.issg.org/database/welcome/ Jelić D., Jelić M., Žutinić P. Ribarstvo. (2010). New data on ichthyofauna of river Česma (central Croatia) 68, (3), 95—104. Jeremic S., Radosavljevic V. (2009) Outbreak of new fish diseases in Serbia. IV International conference ‘‘fishery’’ Belgrade (Serbia), pp 180–185 Kazyak P.F. and R.L. Raesby. (2003). Key to the Freshwater Fishes of Maryland. Available at

http://dnr2.maryland.gov/streams/Documents/fishkey_2003_09edits.pdf Klossner M, (2005). No Bull (Online). Wisconsin, USA: Wisconsin Department of Natural Resources. Koščo J, Košuthová L, Košuth P, Pekári L. (2010). Non-native fish species in Slovak waters: origins and present status. Biologia 65:1057–1063. Koščo, J., Košuth, P., Lusk, S. and Košuthova, L. (2004). Distribution of family Ictaluridae ´ in the Slovakia and in the Czech Republic. Biodiversity

of the Fishes of the Czech Republic V, 45–53. Košuthová L., Koščo J., Letková V., Košuth P. and Manko P. (2009) New records of endoparasitic helminths in alien invasive fishes from the

Carpathian region. August 2009, Volume 64, Issue 4, pp 776–780 Kottelat M. and Freyhof J. (2007). Handbook of European freshwater fishes. Publications Kottelat, Cornol and Freyhof, Berlin. 646 pp. Kreutzenberger, K., Leprieur, F. and Brosse, S. (2008). The influence of the invasive black bullhead Ameiurus melas on the predatory efficiency of

pike Esox lucius L. Journal of Fish Biology. 73, 196-205. Lenhardt M., Markovic G., Hegedis A., Maletin S., Cirkovic M. and Markovic Z. (2011). Non-native and translocated fish species in Serbia and their

impact on the native ichthyofauna. Reviews in Fish Biology and Fisheries. September 2011, Volume 21, Issue 3 , pp 407–421 Leunda P.M., Oscoz J., Elvira B., Agorreta A., Perea S. and Miranda R. (2008). Feeding habits of the exotic black bullhead Ameiurus melas

(Rafinesque) in the Iberian Peninsula: first evidence of direct predation on native fish species. Jour. of Fish Biology 73: 96-114. Louette G. and Declerck, S. (2006). Assessment and control of non‐indigenous brown bullhead Ameiurus nebulosus populations using fyke nets in

shallow ponds. Journal of fish biology, 68(2), 522-531. Lusk S., Lusková V. and Hanel L. (2010) Alien fish species in the Czech Republic and their impact on the native fish fauna Folia Zool. – 59(1): 57–

72. MAGRAMA (2013). Ameiurus melas. http://www.mapama.gob.es/es/biodiversidad/temas/conservacion-de-especies/ameiurus_melas_2013_tcm7-

307160.pdf Mastitsky S.E, Karatayev A. Y., Burlakova L.E. and Adamovich, (2010). Non-native fishes of Belarus: diversity, distribution, and risk classification

using the Fish Invasiveness Screening Kit (FISK). Aquatic Invasions 5: 103–114. McCarraher D.B. and R.W. Gregory. (1970). Adaptability and status of introductions of Sacramento perch, Archoplites interruptus, in North

America. Transactions of the American Fisheries Society 99(4):700-707. Mikhov S. (2000). Checklist of fishes of Bulgaria. FishBase checklist. http://www.fishbase.org Minchin D. (2007). A checklist of alien and cryptogenic aquatic species in Ireland. Aquat Invasions 2:341–366

83

http://link.springer.com/journal/11160/21/3/page/1

http://link.springer.com/journal/11160



Minnesota Department of Natural Resources. (2016). The Minnesota Department of Natural Resources Website (online). Accessed Nov. 28, 2016 at mndnr.gov/copyright

Miranda R., Leunda P.M., Oscoz J., Vilches A., Tobes I., Madoz J. and Martínez-Lage J. (2010). Additional records of non-native freshwater fishes for the Ebro River basin (Northeast Spain). Aquat Invasions 5:291–296

Movchan Yu.V., Talabishka E.M. and Velikopolskiy I.J. (2014). Fishes of the genus Ameiurus (Ictaluridae, Siluriformes) in the Transcarpathian water bodies. Vestnik zoologii, 48(2): 149–156

Moyle P.B. (1986). Fish introductions into North America: patterns and ecological impact. In: Mooney HA, Drake JA (eds) Ecology of biological invasion of North America and Hawaii. Ecological Studies, vol 58. Springer, New York, pp 27–43

Müller J. C., Hidde D. and Seitz A. (2002). Canal construction destroys the barrier between major European invasion lineages of the zebra mussel. The Royal Society, 269 (1496): 1139- 1142

Musil J., Drozd B., Bláha M., Gallardo J.M. and Randák T. (2008). First records of the black bullhead, Ameiurus melas in the Czech Republic freshwaters. Cybium 32:352–354

NatureServe (2013) Ameiurus melas. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org> NatureServe. (2006). NatureServe Explorer: An online encyclopedia of life [Web application]. Version 4.7. NatureServe, Arlington, Va. url:

http://www.natureserve.org/explorer. Novomeska A and Kovac V. (2016). Freshwater resources and fisheries in Slovakia. In Craig JF Ed. Freshwater Fisheries Ecology (pp 191-195).

West Sussex. UK. Novomeska A. and Kovac V. (2009). Life-history traits of non-native black bullhead Ameiurus melas with comments on its invasive potential. J.of

Apllied Ichthyology 25,1: 79-84. Novomeská A., Katina S., Copp G.H., Pedicillo G., Lorenzoni M., Pompei L., Cucherousset J. and Kováč. (2013). Morphological variability of black

bullhead Ameiurus melas in four non-native European populations. Journal of Fish Biology. 82, 1103-1118. Novomeská, A., Kováč, V. and Katina S. (2010). Morphometry of non-native black bullhead Ameiurus melas from Slovakia. Cent. Eur. J. Biol 5(6)

888-893. Nowak M., Kosco J., Popek W. and Epler P. (2010)First record of the black bullhead Ameiurus melas (Teleostei: Ictaluridae) in Poland. Journal of

Fish Biology 76, 1529–1532 Nowak M., Kosco J., Szczerbik P., Mierzwa D. and Popek W. (2010). When did the black bullhead, Ameiurus melas (Teleostei:Ictaluridae), arrive in

Poland?. Arch. Pol. Fish. 18:183-186. Olenin, S., Didžiulis, V., Ovčarenko, I., Olenina, I., Nunn, A. D. and Cowx, I. G. (2008). Review of introductions of aquatic species in

Europe. Report to EC, 41 pp Page L.M. and Burr B.M. (1991). A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston, 432 pp. Pedicillo G., Bicchi A., Angeli V., Carosi A., Viali P. and Lorenzoni M. (2008). Growth of black bullhead Ameiurus melas (Rafinesque, 1820) in

Corbara Reservoir (Umbria – Italy), Knowledge and Management of Aquatic Ecosystems, 389, 05. Perdikaris C., Koutsikos N., Vardakas L., Kommatas D., Simonović P., Paschos I., Detsis V, Vilizzi L. and. Copp G.H. (2015). Risk screening of

non-native, translocated and traded aquarium freshwater fish in Greece using FISK. Fisheries Management and Ecology (doi: 10.1111/fme.12149

84

http://www2.hull.ac.uk/science/pdf/IMPASSE_44142_D1-4.pdf

http://www2.hull.ac.uk/science/pdf/IMPASSE_44142_D1-4.pdf

http://www.iucnredlist.org/

http://mndnr.gov/copyright


Piria M., Povž M., Vilizzi L., Zanella D., Simonović P. and Copp G.H. (2016). Risk screening of non-native freshwater fishes in Croatia and Slovenia using the Fish Invasiveness Screening Kit. Fish Manag Ecol, 23: 21–31. doi:10.1111/fme.12147.

Poulin R., Paterson R.A., Townsend C.R., Tompkins D.M., Kelly D.W. (2011). Biological invasions and the dynamics of endemic diseases in freshwater ecosystems. Freshwater Biology (2011) 56, 676–688.

Pujin V. and Sotirov S. (1966). A study of the nutrition of the dwarf catfish (Ictalurus nebulosus Le Sueur)(In Serbian). Ann Sci Work Fac Agric Novi Sad (Serbia) 10:147–156.

Puntila R, Vilizzi L, Lehtiniemi M, Copp GH (2013) First application of FISK, the Freshwater Fish Invasiveness Screening Kit, in Northern Europe: example of Southern Finland. Risk Anal 33:1397–1403.

Reid S.M., Fox M.G. and Whillans T.H. (1999). Influence of turbidity on piscivory in largemouth bass (Micropterus salmoides). Canadian Journal of Fisheries and Aquatic Sciences 56, 1362–1369.

Reshetnikov YS, Bogutskaya N, Vasil'eva E, Dorofeeva E, Naseka A, Popova O, Savvaitova K, Sideleva V, Sokolov L.(1997). An annotated check-list of the freshwater fishes of Russia. Journal of Ichthyology, 37:687-736.

Ribeiro F., Chaves M. L. , Marques T. A. and Moreira da Costa L. (2006) First record of Ameiurus melas (Siluriformes, Ictaluridae) in the Alqueva reservoir, Guadiana basin (Portugal). Cybium 30(3): 283-284.

Ribeiro F., Collares-Pereira M. J., and P.B. Moyle (2009) Non native fish in the fresh waters of Portugal, Azores and Madeira Islands: a growing threat to aquatic biodiversity. Fisheries Management and Ecology, 16(4), 255-264.

Ribeiro F., Elvira B., Collares-Pereira M. J., and Moyle, P.B. (2008) Life-history of non-native fishes in Iberian watersheds across several invasion stages: a first approach. Biol. Invasions 10:89-102.

Ries C., Pfeiffenschneider M., Engel, E., J.-C. Heidt and M. Lauff. (2014). Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of vertebrates in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 115: 195-201.

Rose C. (2006). Ameiurus melas (On-line), Animal Diversity Web. Accessed May 07, 2015 at http://animaldiversity.org/accounts/Ameiurus_melas/ Rosen PC, Schwalbe CR, Parizek DA Jr, Holm PA, Lowe CH. (1995). Introduced aquatic vertebrates in the Chiricahua region: effects on declining

native ranid frogs. In: Biodiversity and Management of the Madrean Archipelago: the sky island of the southwestern United States and northwestern Mexico. USDA Forest Service General Technical Report RM-GTR-264, 251-261.

Roskov Y., Abucay L., Orrell T., Nicolson D., Flann C., Bailly N., Kirk P., Bourgoin T., DeWalt R.E., Decock W., De Wever A., eds. (2016). Species 2000 and ITIS Catalogue of Life, 2016 Annual Checklist. Digital resource at www.catalogueoflife.org/annual-checklist/2016. Species 2000: Naturalis, Leiden, the Netherlands. ISSN 2405-884X.

Ruiz-Navarro, A., Britton, J. R., Jackson, M. C., Davies, G. D. and Sheath, D. (2015). Reproductive ecology and diet of a persistent Ameiurus melas (Rafinesque, 1820) population in the UK. Journal of Applied Ecology. 31, 201-203.

Rutkayová, J., Biskup, R., Harant, R. (2013) . Ameiurus melas (black bullhead): morphological characteristics of new introduced species and its comparison with Ameiurus nebulosus (brown bullhead) Rev Fish Biol Fisheries 23: 51. doi:10.1007/s11160-012-9274-6

Salvador Vilariño V. (2015). Diagnóstico de la situación de las especies exóticas invasoras dentro del ámbito del proyecto LIFE11 NAT ES/699 MedWetRivers. Sociedad Pública de Infraestructuras y Medio Ambiente de Castilla y León S.A (SOMACYL).

Savini D., Occhipinti–Ambrogi A., Marchini A., Tricarico E., Gherardi F., Olenin S., Gollasch S. 2010: The top 27 animal alien species introduced into Europe for aquaculture and related activities. Journal of Applied Ichthyology, vol. 26, Supplementum 2, pp. 1–7.

85

http://animaldiversity.org/accounts/Ameiurus_melas/




Scarola J.F.(1973). Freshwater Fishes of New Hampshire. New Hampshire, USA: New Hampshire Fish and Game Department, Division of Inland and Marine Fisheries, 131.

Scholz, T. and Cappellaro, H. (1993). The first record of Corallobothrium parafimbriatum Befus et Freeman, 1973 (Cestoda: Proteocephalidea), a parasite of North American catfishes (Ictalurus spp.), in Europe. Folia Parasitologica 40, 105–108

Scott, W. B., Crossman, E. J. (1973). Freshwater fishes of Canada, Fisheries Research Board of Canada. Bull 184. Ottawa, Ont., Canada. Secretariat of NOBANIS. (2012). Risk-mapping for 100 nonnative species in Europe. Copenhagen. Sheath, D. J., Williams, C. F., Reading, A. J. and Britton, J. R. (2015) Parasites of non-native freshwater fishes introduced into England and Wales

suggest enemy release and parasite acquisition. Biological Invasions. 17, 2235-2246. Simonović P., Tosic A., Vassilev M., Apostolou A., Mrdak D., Ristovska M., Kostov V., Nikolic V., Skraba D., Vilizzi L. and Copp G.H. (2013).

Risk assessment of non-native fishes in the Balkans Region using FISK, the invasiveness screening tool for non-native freshwater fishes. Mediterranean Marine Science 14, 2: 369-376.

Tan Y, Tong H.E. (1989). The status of the exotic aquatic organisms in China. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fisheries Society Special Publication [ed. by Silva SSDe], 35-43.

Tarkan A.S., Ekmekçi G., Vilizzi L., Copp G.H. (2014). Risk screening of non-native freshwater fishes at the frontier between Asia and Europe: first application in Turkey of the Fish Invasiveness Screening Kit (FISK). J Appl Ichthyol 30:392–398.

Turchini G.M. and De Silva S.S. (2008). Bio-economical and ethical impacts of alien finfish culture in European inland waters. Aquacult Int (2008) 16:243–272

U.S. Geological Survey. (2016). Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [11/22/2016]. USGS NAS, (2015). USGS Nonindigenous Aquatic Species Database. Gainesville, Florida, USA: USGS. http://nas.er.usgs.gov/ Utne-Palm A.C. (2002). Visual feeding of fish in a turbid environment: physical and behavioural aspects. Marine and Freshwater Behaviour and

Physiology 35, 111–128. Uzunova, E. and Zlatanova, S. (2007). A review of fish introductions in Bulgarian freshwaters. Acta Ichthyologica et Piscatoria, 37:55-61. van der Veer G and Nentwig W. (2014). Environmental and economic impact assessment of alien and invasive fish species in Europe using the

generic impact scoring system. Ecology of Freshwater Fish. doi: 10.1111/eff.12181 Vandekerkhove J., Cardoso A.C. and Boon P. J. (2013) Is there a need for a more explicit accounting of invasive alien species under the Water

Framework Directive? Management of Biological Invasions Volume 4, Issue 1: 25–36 Verbrugge L.N.H., van der Velde G., Hendriks A.J., Verreycken H. and. Leuven R.S.E.W (2012). Risk classifications of aquatic non-native species:

Application of contemporary European assessment protocols in different biogeographical settings. Aquatic Invasions Vol. 7, 1: 49-58. Verreycken H., Anseeuw D., Van Thuyne G., Quataert P. and Belpaire C. (2007). The non-indigenous freshwater fishes of Flanders (Belgium):

review, status and trends over the last decade. J Fish Biol 71(Suppl D):160–172 Verreycken H., Belpaire C., Koen D.G. (2010). Status of two North-American Ameiurus species (Ictaluridae) in Flanders (Belgium) with

preliminary genetic screening of specimens from Belgium, France and the Netherlands. 17th ICAIS, San Diego, USA, 2 September 2010. (www.icais.org/pdf/2010abstracts/Hugo_Verreycken.pdf )

Walberg, E. (2011). Effect of Increased Water Temperature on Warm Water Fish Feeding Behavior and Habitat Use, Journal of Undergraduate Research at Minnesota State University, Mankato: Vol. 11, Article 13. Available at: http://cornerstone.lib.mnsu.edu/jur/vol11/iss1/13

86

http://www.icais.org/pdf/2010abstracts/Hugo_Verreycken.pdf

http://nas.er.usgs.gov/




Welcomme R.L. (1988). International introductions of inland aquatic species. FAO Fisheries Technical Paper, No. 294:x + 318 pp Wheeler A. (1992). A list of the common and scientific names of fishes of the British Isles. J. Fish Biol., 41(1):1-37. Wheeler A.C. (1979). Ictalurus melas (Rafinesque, 1820) and I. nebulosus (Lesueur, 1819): the North American catfishes in Europe. Journal of Fish

Biology, 12:435-439 Wiesner, C., Wolter, C., Rabitsch, W. and Nehring, S. (2010). Gebietsfremde Fische in Deutschland und Österreich und mögliche Auswirkungen des

Klimawandels. Bundesamtn für Naturschutz. 279: 192 S. Wilhelm A. (1998). Black bullhead (Ictalurus melas Rafinesque, 1820) (Pisces: Ostariophysi: Bagroidae), a new species of fish recently found in Ro-

manian waters. Trav Mus Natl Hist Nat Grigore Antipa 40:377–381 Wittenberg R. (2005). An inventory of alien species and their threat to biodiversity and economy in Switzerland. CABI Bioscience Switzerland

Centre report to the Swiss Agency for Environment, Forests and Landscape. The environment in practice 0629. Bern, : Federal Office for the Environment, 155.

Wolter C and Röhr F. (2010). Distribution history of non-native freshwater fish species in Germany: how invasive are they? J Appl Ichthyol 26(Suppl 2):19–27.

Zięba G., Copp G. H., Davies G. D., Stebbing P., Wesley K. J. and Britton J. R. (2010). Recent releases and dispersal of non – native fishes in England and Wales, with emphasis on sunbleak Leucaspius delineatus (Heckel, 1843). Aquatic Invasions, 5, 2: 155 – 161.

87





circabc.europa.eu · Web viewThis Risk Assessment refers to genus Ameiurus and includes information...

Documents

Transcript of circabc.europa.eu · Web viewThis Risk Assessment refers to genus Ameiurus and includes information...