IMPACTS OF URBANISATION AND METAL

POLLUTION ON FRESHWATER TURTLES

A thesis submitted in fulfilment of the requirements for the degree of

Doctor of Philosophy

by

Carol Lindsay Browne

School of Biological Sciences

University of Sydney

August 2004

SUMMARY

Over 85% of Australia’s population live in urban areas and many turtle populations

occur on Australia’s east coast where urban development is particularly concentrated.

In the state of NSW, over half of the freshwater coastal wetlands have been highly

modified or completely destroyed, and urban freshwater creeks often have only a

narrow strip of weedy bushland left along their banks. Even though habitat

degradation may result in declines in density and distribution of turtle populations,

there are few data on Australian freshwater turtles in urban areas.

In addition to extreme habitat alteration, urban waterways are innundated with

anthropogenic contaminants from sources including wet weather surface runoff and

industrial and sewage discharges. Pollutants can impact all systems of the body with

potentially severe effects on reproduction and survival that can result in deterioration

of animal populations. Turtles are particularly susceptible to anthropogenic

contaminants due to their intimate contact with the aquatic environment, an often high

trophic level, their ability to accumulate toxins, and their longevity. For almost all

contaminants, the degree of accumulation in and effect on reptile species is unknown.

Sublethal effects in field situations are particularly poorly studied and have never

been documented in pleurodiran turtles.

As a pioneering work in Australian reptile ecotoxicology, this thesis takes a broad

approach, but focuses primarily on immunotoxicity and reproductive toxicity – two

areas that greatly impact the size and continuance of animal populations. The aim of

the thesis is to provide baseline data on haematology, cellular immunology and tissue

metal concentrations for freshwater turtles in Sydney – data which were lacking for

all Australian turtle species prior to this study. After initial assessment of the

distribution and density of freshwater turtles in Sydney, the study examines the

potential for Sydney’s turtles as sentinel species for measuring the effects of pollution

on haematology, cellular immunity, and parasite loads; and considers the relationships

between urban metal pollution and reproductive variables. The relative suitability of

non-lethally sampled tissues (blood, carapace, egg) for use in biomonitoring is also

assessed.

i

Three species of Australian freshwater turtles were found in the Sydney region, with

Chelodina longicollis occurring naturally in the area, and populations of Emydura

macquarii and Elseya latisternum likely to have originated from translocated

individuals. The North American turtle Trachemys scripta elegans was not

encountered during this study despite concerns that it was establishing in the Sydney

area. Chelodina longicollis populations were widespread, although poor recruitmment

was indicated by low capture rates and comparatively low percentage of juveniles at

some sites. Not so widespread, Emydura macquarii was present in much larger

numbers than C. longicollis and with a high juvenile component in some areas of

southeastern Sydney.

I provide information on erythrocyte and leucocyte parameters in C. longicollis over a

range of sites, pollution conditions, and seasons. In C. longicollis, numbers of

lymphocytes, heterophils and eosinophils varied over sites, but not due to pollution

from sewage treatment plant outfalls. There was significant temporal variation in

erythrocyte, lymphocyte, eosinophil, heterophil, and basophil number, the

heterophil:lymphocyte ratio, and haematocrit, but not consistently among sites. Future

studies should ensure simultaneous sampling across sites for comparative purposes.

Similarly, turtle populations downstream of sewage treatment plant outfalls showed

no consistent difference in number, body condition, blood haemogregarine load, or

leech (haemogregarine vector) load from upstream populations. Leech (Helobdella

papillornata, with some Placobdella sp.) load and haemogregarine numbers increase

dramatically once C. longicollis reach a carapace of 110 mm. The number of leeches

on turtles varied across season, year, and site. Turtles with large numbers of leeches

had reduced haematocrit, but the presence of leeches had no other correlations with

haematological parameters. Haemogregarine numbers did not change across season or

year, and were not correlated with haematological variables. The hypothesis that

pollutants lead to an increase in normal blood protozoa due to reduced immunity thus

was not supported.

The concentration of metals in C. longicollis and E. macquarii carapace and in lagoon

sediments varied significantly over four urban and four national park sites, but not

based on this split. Pollution in periurban areas, such as illegal dumping of toxic

wastes and atmospheric deposition of pollutants, means that each site must be

ii

classified separately as to degree of metal pollution. There was little or no affect of

species, size, sex, or gravidity on metal concentrations in the carapace of adult turtles.

Emydura macquarii had higher concentrations of blood Fe than C. longicollis from a

different site, but this is possibly due to an increase in haemoglobin resulting from the

site’s low aquatic oxygen concentration rather than any increased environmental

exposure.

Chelid turtles in Sydney do not show much promise as a biomonitoring tool. Carapace

analysis is largely discounted as a potential tool for metal biomonitoring due to poor

correlations between potentially toxic metals in non-lethally samplable tissues

(carapace, claw) and internal organs (liver, kidney) or bone (femur). However,

carapace metal concentrations still potentially reflect long-term metal presence or

different dietary exposures as evidenced by the significant variation in concentrations

over sites. A rare correlation was found for concentrations of aquatic Pb and carapace

Pb, and a correlation was also found for concentrations of blood Pb and carapace Pb

in E. macquarii. Thus any potential for tissue biomonitoring seems to lie with this

highly ecotoxicologically relevant metal. Although two other ecotoxicologically

relevent metals, Cu and Se, were significantly higher in egg contents of C. longicollis

compared to E. macquarii, these elements are also essential and a lack of baseline

values means it is not known if this simply reflects natural taxonomic variation. Ni, a

metal of toxicological concern in sea turtles, was not present in egg contents, and only

variably present in eggshell. The absence of Pb from eggs, despite its presence in

many maternal tissues, suggests that selective metal uptake into eggs may be

protective of toxic elements, rather than eggs serving as a maternal method of toxic

metal elimination as has been previously suggested. The paucity of toxic metal

detection in eggs renders them unlikely tissues for biomonitoring.

The maternal tissue or tissues or environmental source from which egg metals

originate remains obscure, although a significant negative effect of maternal carapace

concentrations of Ca and Mg on eggshell thickness in E. macquarii indicates that

there may be mobilisation of Ca and Mg from the carapace for eggshell formation.

The only metal whose eggshell concentration correlated with eggshell thickness was

Mg, indicating that ecotoxic metals previously associated with eggshell thinning are

not problematic in the Sydney chelids. As with North American turtles living at

iii

iv

polluted sites, none of the chelid hatchlings were found to have any overt

abnormalities. Hatching success was poor and hatching mass low for eggs of both C.

longicollis and E. macquarii, although results from natural nests are required to

determine whether or not this was an outcome of hormonally-induced oviposition and

artificial incubation.

It is difficult to interpret metal concentrations found in the soft tissues, calcified

tissues, and eggs of chelonians due to the paucity of comparative data, and much more

research is required on tissue metal concentrations before patterns will emerge. This

especially applies to pleurodires for which no previous information is available. From

comparisons with the limited data available for other freshwater turtles, marine

turtles, and other aquatic reptiles, it does not appear that Sydney’s turtle populations

have unusually high metal concentrations in tissues. Exclusion of toxic metals such as

Pb from the egg may also be protective to the developing embryo. An ability to live in

polluted habitats, while limiting the accumulation of toxic contaminants, may be one

key to their persistence in urban waterways from which other freshwater fauna have

disappeared. Reproductive impacts such as low embryo survival and small hatchling

weights require more rigorous examination, but may have less effect on these animals

which have such naturally high egg and hatchling mortality.

Although it was generally hard to demonstrate biochemical, physiological or

population impacts of contaminants, C. longicollis from a site with severe sewage

pollution did display unusual alterations in a number of haematological variables,

body condition, and carapace bone structure. Despite this, the population was large

and had a comparatively high ratio of juveniles. Additionally, the adverse

haematological alterations appeared reversible. Thus, successful populations in

Sydney probably are more dependent on basic ecological needs being met, than on

low levels of environmental contaminants. The ongoing persistence of chelid

populations in Sydney is likely to be dependent to some extent on their opportunistic

diets, which generally make animals less vulnerable to habitat modification and the

reduction in prey item diversity following pollution (Mason 1996, Allanson &

Georges 1999), with a further benefit possibly bestowed at some sites on E. macquarii

by its omnivory.

v

ACKNOWLEDGEMENTS

Firstly I would like to thank my granting bodies, who provided much needed support for field and

laboratory work. Field work was supported by the Royal Zoological Society of NSW for the

Reproductive Study, and by the Peter Rankin Trust Fund for Herpetology and the Linnean Society

of NSW for the Immune Study. This financial support also provided great moral encouragement.

Most of all, I am greatly indebted to AINSE (Australian Institute for Nuclear Science and

Engineering) for their postgraduate award including generous financial support of my laboratory

analyses performed at the Environmental Division of ANSTO (Australian Nuclear Science and

Technology Organisation), as well as the student stipend which provided some seriously needed

financial relief. Their support allowed for a much more indepth scientific study than could ever

have otherwise been realised. I would also like to thank Ray Ritchie for originally suggesting the

application. Additional thanks go to my mechanic Steve and the Mighty Boy, and my brother

Derrick and the Trumps Mazda 131 for providing (really really small) emergency field work

vehicles when the old EK was all quiet on the braking, accelerating or steering fronts.

I extend a deep gratitude to my supervisor Associate Professor Michael Thompson and the

University of Sydney who found me wandering lost and orphaned, and took me on very late in my

candidature and encouraged and guided me through the thesis writing process. I was very

privileged to be part of the Thommo Lab. Thanks also to my associate supervisor Dr Ross Jeffree

who was very supportive of all the work I performed at ANSTO.

When you’re feeling overwhelmed, lonely & isolated, plus you’re wearing large baggy green

rubber pants and carrying quantities of appearingly illegal fishing equipment, it can make an

indescribable difference to have the occasional bit of company during field work. For the first half

of ‘my time’, biggest thanks of all goes to my old school buddy, Michael Payne, who fortunately

suffered prolonged bouts of unemployment during my field studies. When suspended on an

overhanging branch above a ranging torrent trying to retrieve a net, it was reassuring to have

someone there to comment ‘maybe you shouldn’t be doing that Brownes’. Despite full body

submersions in fouled waters, chronically leaking waders, cyanobacterial rashes, psychotic turtle

attacks, foul fish (the hideously ugly bullrouts and the truly repellent giant thrashing carp), a

metamorphosing car cabin temperature and pressure, booby-trapped paths, and crazed exhausted

frazzled depressed PhD student for sole primate company, Payney was always a willing,

uncomplaining, and cheerful research assistant (as long as he was fed a kebab every four hours).

Thanks to those others who broke the loneliness and isolation for a day or two: Chris Schell,

Carolyn Herlihy, Derrick Browne, Bill Browne, Jenny Browne, Glenda Browne, & Glenn Shea. To

all those who came and carried or rowed nets long distances to Lake Toolooma, Jibbons Lagoon,

Marley Lagoon or Kangaroo Creek in my third and final season (Robyn Stevenson, Ted Martin,

Michael Payne, Glenn Shea, Karen Darby, Tony Murphy & Roger Browne)…I couldn’t have done

it without you. And to Dean Metcalf, thanks muchly for helping me pull nets out of trees after The

Flood. Thanks also to Owen Moore and Mita Atkins from Process Engineering Technologies for

pulling turtles out of the poo pit.

For the second half of my incarceration, biggest thanks go to Glenn Shea for unwavering

nutritional, emotional, and statistical support, for showering with turtles, providing ‘laboratory

facilities’, and for the tricksy turtle tipping tip. You are a star! Many thanks also go to: My father,

Leigh Browne, for desperately needed, whoppingly large and ever increasing financial loans. My

brother, Derrick Browne, for employment at his fine establishment (Trumps Bridge Centre,

Mosman), and letting me work such crazy hours. My sister, Glenda Browne, her partner, Jon

Jermey, and my nephew, Bill Browne, for thorough and expert editorial comment. My niece, Jenny

Browne, for not asking me the top thesis question: ‘And what job do you anticipate getting on the

basis of hopping into creeks and playing with turtles?’. Craig & Gabrielle Latta for the turtle

induction method. Chris & Leah Schell for generosity and friendship – you were lights in a dark

place. The insanely furious bull at Redbank creek for not stampeding me. God for limiting The

Flood to two days and two nights. Bookie the cat, for listening. Kids at creeks everywhere for their

interest & enthusiasm, and for thinking I had a great ‘job’. Strange lurking men at creeks

everywhere for not violating me. Levelle of Withers Rd, Kellyville, for the tour of his

architecturally unique back yard and encouraging me to the top of his rickety old 3-story dead-tree-

house. And of course many thanks to all those people who stole nets, threatened me, or were just

generally obnoxious or obstructive, for reminding me that there are, and always will be, complete

bastards in the world.

I also extend my gratitude to those who provided access to private property. Jim (manager) and the

residents of St Vincents de Paul’s drug and alcohol rehabilitation property at Quakers Hill for their

interest and access to Breakfast Creek, Sheryl and Lou of Terrace Road, North Richmond, for

access to Redbank Creek, the rangers at Nurragingy Reserve for access to Eastern Creek, the

owners of 36 Poole Rd for access to Smalls Creek, the residents at the end of Third Ave in Lugarno

for access to South Creek, Castle Hill STP for access to the sludge lagoon, Rouse Hill STP for

access to Second Ponds Creek, Riverstone STP for the key to the gate for access to Eastern Creek,

and Centennial Park and Moore Park Trust for access to Model Yacht Pond, Kensington Pond, and

Busby’s Lagoon.

But most importantly of all…thanks to the 170 metres, and 552 kilograms of turtles that so

enthusiastically participated in this study.

vi

THE REQUEST ‘I should like to have it explained’, said the Mock Turtle.

Lewis Carroll 1832-1898: Alice’s Adventures in Wonderland, 1865

THE COMMENCEMENT In a situation where the consequences of wrong decisions are so awesome, where

a single bit of irrationality can set a whole train of traumatic events in motion, I do

not think that we can be satisfied with the assurance that ‘most people behave

rationally most of the time’. C. E. Osgood: in Norman Dixon, On the Psychology of Military Incompetence, 1976

THE FIELD WORK We only wish to represent things as they are, and to expose the error of

believing that mere bravo without intellect can make himself

distinguished… Karl von Clausewitz 1780-1831: On War, 1832-4

THE WRITING Never express yourself more clearly than you think.

Niels Bohr 1885-1962: in Abraham Pais, Einstein Lived Here, 1994

THE SUBMISSION Now this is not the end. It is not even the beginning of the

end. But it is, perhaps, the end of the beginning. Winston Churchill 1874-1965: London speech, 1942

vi

TABLE OF CONTENTS

Page

Summary i

Acknowledgements v

Abbreviations xv

SECTION A: GENERAL INTRODUCTION 1

A.1 Chelidae 2

A.1.1 Morphology 3

A.1.2 Habitat 4

A.1.3 The Eastern Longneck Turtle (Chelodina longicollis, Shaw 1794) 4

A.1.3.1 Distribution & Habitat 4

A.1.3.2 Morphology 5

A.1.3.3 Diet 5

A.1.3.4 Migration 6

A.1.4 The Macquarie Turtle (Emydura macquarii, Gray 1830) 7

A.1.4.1 Distribution & Habitat 7

A.1.4.2 Diet 8

A.1.5 Saw-shelled Turtle (Elseya latisternum, Gray 1867) 8

A.2 Study Area: Sydney Basin 10

A.2.1 Geography and Waterbodies 10

A.2.2 History of Urbanisation 10

A.2.2.1 The History of Water Pollution Control in Sydney 12

A.2.2.2 The History of Air Pollution Control in Sydney 14

A.3 Pollution 14

A.3.1 Metal Pollution 15

A.3.2 Bioaccumulation 18

A.3.3 Biomonitoring 20

A.3.3.1 Comparison with Chelydra serpentina 21

A.3.4 Metal Effects 21

A.3.4.1 Metals & Reptiles 22

A.4 Aims 23

vii

SECTION B: GENERAL METHODS 25

B.1 Fieldwork 25

B.1.1 Trapping 25

B.1.1.1 Fyke nets 25

B.1.1.2 Yabby traps 25

B.1.1.3 Snorkelling 26

B.1.2 Transport & Holding 26

B.2 Turtles 26

B.2.1 Identification 26

B.2.2 Measurement 27

B.2.3 Aging 27

B.2.4 Marking 28

B.2.5 Tissue Sampling 30

B.2.5.1 Carapacial Bone 30

B.2.5.2 Blood 30

B.3 Study Sites 31

SECTION C: SYDNEY TURTLE SURVEY 33

C1 Survey Introduction 34

C1.1 Distribution of Turtles in Sydney 34

C1.1.1 Local Species 34

C1.1.2 Exotic Species 35

C1.2 Maturity 37

C1.3 Aims 37

C2 Survey Methods 38

C2.1 Survey A 38

C2.1.1 Site Selection 38

C2.1.2 Trapping 38

C2.1.3 Site Descriptions 38

C2.2 Survey B 43

C2.2.1 Site Selection 43

C2.2.2 Trapping 43

viii

C2.2.3 Site Descriptions 43

C2.3 Turtle Processing 45

C2.3.1 Sexing 45

C3 Survey Results 46

C3.1 Survey A – Specific Comments 46

C3.2 Survey B – Specific Comments 46

C3.3 Sydney Surveys – General Results 48

C3.3.1 Turtle Morphology 48

C3.3.2 Size at Maturity/Sexing 48

C3.3.3 Effect of Baiting 48

C3.3.4 Non-Turtle Captures 49

C3.4 Comparison of Turtles over Sites 49

C3.4.1 Species Distribution 49

C3.4.2 Measurement Correlations 50

C3.4.3 Size Distribution 51

C3.4.4 Growth Curves & Body Condition 54

C3.5 Turtle Health 58

C4 Survey Discussion 60

C4.1 Trapping 60

C4.1.1 Activity 60

C4.1.2 Baiting 61

C4.2 Comparison of Turtles over Sites 61

C4.2.1 Species 61

C4.2.2 Translocated Turtle Species 63

C4.2.3 Centennial Park 64

C4.2.4 Measurement Correlations 67

C4.2.5 Size 68

C4.2.6 Growth Curves & Body Condition 70

C4.3 Other Turtle Aspects 72

C4.3.1 Maturity 72

C4.3.2 Turtle Health 75

C4.3.3 Fish 78

C4.4 Summary 80

ix

SECTION D: POLLUTION, BLOOD CELLS, & PARASITISM 82

D1 Blood Introduction 83

D1.1 Pollution and Immunity 83

D1.2 Disease 84

D1.2.1 Haemogregarines 85

D1.2.2 Leeches 86

D1.3 Haematopoietic Toxicity 87

D1.3.1 Metals 88

D1.4 Aims 89

D2 Blood Methods 91

D2.1 Site Selection 91

D2.2 Site Descriptions 94

D2.2.1 Quakers Hill STP Set 94

D2.2.2 Riverstone STP Set 97

D2.2.3 North Richmond STP Set 99

D2.2.4 Rouse Hill STP Set 101

D2.2.5 Castle Hill STP 103

D2.3 Water Metals 104

D2.4 Trapping 104

D2.5 Laboratory Procedures 107

D2.5.1 Leeches 107

D2.5.2 Turtle Processing 107

D2.5.3 Blood Processing 108

D3 Blood Results 109

D3.1 Turtle Captures 109

D3.1.1 Water Temperature 109

D3.1.2 Turtle Numbers 109

D3.1.3 Size at maturity 111

D3.1.4 Growth 111

D3.2 Sludge Lagoon 112

D3.3 Body condition 113

D3.3.1 Season 115

D3.3.2 Site 115

x

D3.4 Fish 117

D3.5 STPs and Blood Parameters 119

D3.5.1 Blood Sample Volume 121

D3.5.2 Blood Sampling Time 122

D3.5.3 Distributions of blood variables 123

D3.5.4 Season Effect 123

D3.5.5 STP Effect 129

D3.5.6 Metal Effects 143

D3.5.7 Haemogregarines 145

D3.6 Leeches 149

D4 Blood Discussion 153

D4.1 Turtle Captures 153

D4.1.1 Population Size 153

D4.1.2 Site Fidelity 154

D4.1.3 Growth at Breakfast Creek 155

D4.2 Body Condition 155

D4.2.1 Season 155

D4.2.2 Site 156

D4.3 Metals, Turtle Captures, and Body Condition 157

D4.4 Erythrocytes 158

D4.5 Thrombocytes 161

D4.6 Leucocytes 162

D4.6.1 Lymphocytes 163

D4.6.2 Monocytes 164

D4.6.3 Heterophils 165

D4.6.4 Eosinophils 165

D4.6.5 Basophils 166

D4.6.6 Heterophil:Lymphocyte Ratio 167

D4.7 Haemoparasites 168

D4.7.1 Leeches 168

D4.7.2 Haemogregarines 176

D4.8 Summary 178

xi

SECTION E:

METAL BIOACCUMULATION & TISSUE BIOMONITORING 182

E1 Metal Bioaccumulation Introduction 183

E1.1 Biomonitoring 183

E1.1.1 Bone 185

E1.1.2 Blood 187

E1.2 Aims 187

E2 Metal Bioaccumulation Methods 190

E2.1 Outline 190

E2.2 Sites 190

E2.2.1 General Location 190

E2.2.2 Descriptions 192

E2.3 Field Work 198

E2.3.1 Trapping 198

E2.3.2 Water and Sediment sampling 198

E2.3.3 Field Turtle Processing 200

E2.4 Laboratory Turtle Processing 200

E2.4.1 Hard Tissue Structure 201

E2.5 Preparation for Metal Analysis 201

E2.5.1 Tissues 201

E2.5.2 Environmental Samples 203

E2.6 Metal Analysis 204

E2.6.1 Quality Control 204

E2.6.2 Microwave Digestion of Samples 204

E2.6.3 ICPMS & ICPAES Digest Analysis 205

E3 Metal Bioaccumulation Results 207

E3.1 Turtle Captures 207

E3.1.1 Turtle Size and Body Condition 207

E3.2 Metal Analysis 208

E3.2.1 Quality Control 208

E3.2.2 Metal Detection 210

E3.3 Water and Sediment 210

E3.3.1 Water Quality 210

xii

E3.3.2 Metals in Water 211

E3.3.3 Metals in Sediment 212

E3.3.4 Metals in Water, Sediment, and Carapace 212

E3.4 Organ Metal Distribution 214

E3.5 Metals in Carapace 217

E3.5.1 Size 217

E3.5.2 Sex 217

E3.5.3 Species Differences 218

E3.5.4 Site Differences 223

E3.6 Metals in Blood 223

E3.6.1 Blood vs Environment 223

E3.6.2 Blood vs Carapace 230

E3.7 Bone Structure 232

E4 Metal Bioaccumulation Discussion 235

E4.1 Turtle Captures 235

E4.2 Environmental Parameters & Urbanisation 236

E4.2.1 Physicochemical Parameters 236

E4.2.2 Environmental Metals 238

E4.3 Biomonitoring 245

E4.4 Metals in Organs 247

E4.4.1 Liver & Kidney 248

E4.4.2 Bone 256

E4.5 Carapace Metals 259

E4.5.1 Variations in Carapace Metal Concentration 259

E4.5.2 Non-Essential Elements – Specific Comments 265

E4.6 Blood Metals 268

E4.6.1 Blood Metal Toxicity 271

E4.7 Summary 274

SECTION F: METALS & REPRODUCTION 277

F1 Metals & Reproduction Introduction 278

F1.1 Reproductive Aspects of Turtles 278

F1.1.1 Nesting 279

xiii

F1.1.2 Eggs 280

F1.1.3 Hatching 280

F1.2 Reproductive Toxicity of Metals 281

F1.2.1 Metals in Eggs 281

F1.2.2 Reproductive Toxicity of Metals on Young 282

F1.2.3 Reproductive Toxicity of Metals on Adults 282

F1.3 Aims 284

F2 Metals & Reproduction Methods 285

F2.1 Induction of Oviposition 285

F2.2 Egg Incubation 285

F2.3 Eggshell Thickness 286

F3 Metals & Reproduction Results 287

F3.1 Reproductive Parameters 287

F3.1.1 Clutch Size 287

F3.1.2 Egg Dimensions 287

F3.1.3 Eggshell Thickness 287

F3.1.4 Hatchlings 289

F3.2 Maternal Carapace Metals 292

F3.3 Egg Metals 292

F4 Metals & Reproduction Discussion 301

F4.1 Clutch Parameters 301

F4.1.1 Clutch Size 301

E4.1.2 Egg Size 303

F4.2 Hatchlings 304

E4.2.1 Egg Incubation 304

F4.2.2 Hatchlings 305

F4.3 Egg Metals 306

F4.3.1 Eggshell Thickness 308

F4.3.2 Egg Metal Concentrations 309

F4.4 Summary 313

BIBLIOGRAPHY 315

xiv

ABBREVIATIONS

ABS Australian Bureau of Statistics

AMG Australian map grid

ANOVA analysis of variance

ANSTO Australian Nuclear Science and Technology Organisation

ANZECC Australian and New Zealand Environment and Conservation Council

BOD biological oxygen demand

CBD central business district

CCL midline curved carapace length

CH Castle Hill (Section D)

Cl Chelodina longicollis

CL straight-line carapace length

cond. conductivity

CONT control creek (Section D)

CW width of the carapace at the widest point

DO dissolved oxygen

DORM-2 dogfish muscle standard reference material

down downstream (Section D)

E Effort = number of 24-hour fyke net periods

EDP an iodine antiseptic powder

EDTA disodium ethylenediamine-tetraacetate

Em Emydura macquarii

EPA Environment Protection Authority (Australia)

HG haemogregarine

ICP-MS inductively coupled plasma mass spectrometry

ICP-AES inductively coupled plasma atomic emission spectrometry

K-W Kruskal-Wallis

LCR Lane Cove River

metal symbols see Table E2.2 at the end of Section E2

na not analysed

nd not detected

NPWS NSW National Parks & Wildlife Service

NR North Richmond (Section D)

xv

NRMA National Roads and Motorists’ Association Ltd

NSW New South Wales (Australian state)

P1 park site 1, Lake Toolooma (Section E)

P2 park site 2, Kangaroo Creek (Section E)

P3 park site 3, Jibbons Lagoon (Section E)

P4 park site 4, Marley Lagoon (Section E)

PCV % packed red cell volume, haematocrit

Per E per effort = number of captured turtles/E

PLmax length of the plastron from the most anterior to most posterior point

PLmin length of the plastron from the most anterior point to the anal notch

PWa width of the anterior lobe of the plastron

PWp width of the posterior lobe of the plastron

QH Quakers Hill (Sections D & F)

R Riverstone (Section D)

RBC red blood cell, erythrocyte

re animals recaptured within the same trapping period

RH Rouse Hill (Sections D & F)

S1 first summer trapping period (Section D)

S2 second summer trapping period (Section D)

SD standard deviation

SE standard error

SEM scanning electron microscopy

SIMS secondary ion mass spectrometry

STP sewage treatment plant

TDS total dissolved solids

U1 urban site 1, Model Yacht Pond (Section E)

U2 urban site 2, Botany Swamps (Sections E & F)

U3 urban site 3, Sir Joseph Banks Park (Section E)

U4 urban site 4, Bicentennial Park (Sections E & F)

up upstream (Section D)

W post-winter trapping period (Section D)

WBC white blood cell, leucocyte

xvi