Register      Login
Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Declines of freshwater turtles associated with climatic drying in Australia’s Murray–Darling Basin

Bruce C. Chessman
+ Author Affiliations
- Author Affiliations

New South Wales Office of Environment and Heritage, PO Box 3720, Parramatta, NSW 2150, Australia. Email: Bruce.Chessman@environment.nsw.gov.au

Wildlife Research 38(8) 664-671 https://doi.org/10.1071/WR11108
Submitted: 22 June 2011  Accepted: 10 October 2011   Published: 23 November 2011

Abstract

Context: While much attention has been paid to the effects of global temperature increases on the geographical ranges and phenologies of plants and animals, less is known about the impacts of climatically driven alteration of water regimes.

Aims: To assess how three species of freshwater turtle in Australia’s Murray–Darling Basin have responded to long-term decline in river flow and floodplain inundation due to climatic drying and water diversions.

Methods: Turtle populations were sampled in a section of the Murray River and its floodplain in 1976–82 following a wet period and in 2009–11 at the end of the most severe drought on record. Catch per unit effort, proportional abundance in different habitat types and population structure were assessed in both periods.

Key results: Catch per unit effort in baited hoop nets declined by 91% for the eastern snake-necked turtle (Chelodina longicollis) and 69% for the Murray turtle (Emydura macquarii), but did not change significantly for the broad-shelled turtle (Chelodina expansa). In addition, total catches from a range of sampling methods revealed a significantly reduced proportion of juvenile C. longicollis and E. macquarii in 2009–11, suggesting a fall in recruitment.

Key conclusions: The decline of C. longicollis was likely due mainly to drought-induced loss of critical floodplain habitat in the form of temporary water bodies, and that of E. macquarii to combined effects of drought and predation on recruitment. C. expansa seems to have fared better than the other two species because it is less vulnerable to nest predation than E. macquarii and better able than C. longicollis to find adequate nutrition in the permanent waters that remain during extended drought.

Implications: Declining water availability may be a widespread threat to freshwater turtles given predicted global impacts of climate change and water withdrawals on river flows. Understanding how each species uses particular habitats and how climatic and non-climatic threats interact would facilitate identification of vulnerable populations and planning of conservation actions.


References

Alcamo, J., Flörke, M., and Märker, M. (2007). Future long-term changes in global water resources driven by socio-economic and climatic changes. Hydrological Sciences Journal 52, 247–275.
Future long-term changes in global water resources driven by socio-economic and climatic changes.Crossref | GoogleScholarGoogle Scholar |

Austin, J., Zhang, L., Jones, R. N., Durack, P., Dawes, W., and Hairsine, P. (2010). Climate change impact on water and salt balances: an assessment of the impact of climate change on catchment salt and water balances in the Murray–Darling Basin, Australia. Climatic Change 100, 607–631.
Climate change impact on water and salt balances: an assessment of the impact of climate change on catchment salt and water balances in the Murray–Darling Basin, Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXms1Sitrk%3D&md5=cc1bb0c64d1be1d6f900b64153837b2eCAS |

Beesley, L. S., Howard, K. M., Joachim, L., and King, A. J. (2010). Cultural conservation of freshwater turtles in Barmah–Millewa Forest. Arthur Rylah Institute for Environmental Research Technical Report Series No. 203. Department of Sustainability and Environment, Heidelberg, Victoria.

Booth, D. T. (2010). The natural history of nesting in two Australian freshwater turtles. Australian Zoologist 35, 198–203.

Bowen, K. D., and Janzen, F. J. (2005). Rainfall and depredation of nests of the painted turtle, Chrysemys picta. Journal of Herpetology 39, 649–652.
Rainfall and depredation of nests of the painted turtle, Chrysemys picta.Crossref | GoogleScholarGoogle Scholar |

Bowen, K. D., Spencer, R.-J., and Janzen, F. J. (2005). A comparative study of environmental factors that affect nesting in Australian and North American freshwater turtles. Journal of Zoology 267, 397–404.
A comparative study of environmental factors that affect nesting in Australian and North American freshwater turtles.Crossref | GoogleScholarGoogle Scholar |

Buhlmann, K. A., Akre, T. S. B., Iverson, J. B., Karapatakis, D., Mittermeier, R. A., Georges, A., Rhodin, A. G. J., van Dijk, P. P., and Gibbons, J. W. (2009a). A global analysis of tortoise and freshwater turtle distributions with identification of priority conservation areas. Chelonian Conservation and Biology 8, 116–149.
A global analysis of tortoise and freshwater turtle distributions with identification of priority conservation areas.Crossref | GoogleScholarGoogle Scholar |

Buhlmann, K. A., Congdon, J. D., Gibbons, J. W., and Greene, J. L. (2009b). Ecology of chicken turtles (Deirochelys reticularia) in a seasonal wetland ecosystem: exploiting resource and refuge environments. Herpetologica 65, 39–53.
Ecology of chicken turtles (Deirochelys reticularia) in a seasonal wetland ecosystem: exploiting resource and refuge environments.Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1978). Ecological studies of freshwater turtles in south-eastern Australia. Ph. D. Thesis, Monash University, Melbourne.

Chessman, B. C. (1983a). A note on aestivation in the snake-necked turtle, Chelodina longicollis (Shaw) (Testudines: Chelidae). Herpetofauna 14, 96–97.

Chessman, B. C. (1983b). Observations on the diet of the broad-shelled turtle, Chelodina expansa Gray (Testudines: Chelidae). Australian Wildlife Research 10, 169–172.
Observations on the diet of the broad-shelled turtle, Chelodina expansa Gray (Testudines: Chelidae).Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1984a). Evaporative water loss from three south-eastern Australian species of freshwater turtle. Australian Journal of Zoology 32, 649–655.
Evaporative water loss from three south-eastern Australian species of freshwater turtle.Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1984b). Food of the snake-necked turtle, Chelodina longicollis (Shaw) (Testudines: Chelidae) in the Murray Valley, Victoria and New South Wales. Australian Wildlife Research 11, 573–578.
Food of the snake-necked turtle, Chelodina longicollis (Shaw) (Testudines: Chelidae) in the Murray Valley, Victoria and New South Wales.Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1986). Diet of the Murray turtle, Emydura macquarii (Gray) (Testudines: Chelidae). Australian Wildlife Research 13, 65–69.
Diet of the Murray turtle, Emydura macquarii (Gray) (Testudines: Chelidae).Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1988a). Habitat preferences of freshwater turtles in the Murray Valley, Victoria and New South Wales. Australian Wildlife Research 15, 485–491.
Habitat preferences of freshwater turtles in the Murray Valley, Victoria and New South Wales.Crossref | GoogleScholarGoogle Scholar |

Chessman, B. C. (1988b). Seasonal and diel activity of freshwater turtles in the Murray Valley, Victoria and New South Wales. Australian Wildlife Research 15, 267–276.
Seasonal and diel activity of freshwater turtles in the Murray Valley, Victoria and New South Wales.Crossref | GoogleScholarGoogle Scholar |

CSIRO (2008). Water availability in the Murray. A report to the Australian Government from the CSIRO Murray–Darling Basin Sustainable Yields Project. CSIRO: Canberra.

Dickman, C. R. (1996). Impact of exotic generalist predators on the native fauna of Australia. Wildlife Biology 2, 185–195.

Döll, P., and Zhang, J. (2010). Impact of climate change on freshwater ecosystems: a global scale analysis of ecologically relevant river flow alterations. Hydrology and Earth System Sciences Discussions 7, 1305–1342.
Impact of climate change on freshwater ecosystems: a global scale analysis of ecologically relevant river flow alterations.Crossref | GoogleScholarGoogle Scholar |

Erwin, K. L. (2009). Wetlands and global climate change: the role of wetland restoration in a changing world. Wetlands Ecology and Management 17, 71–84.
Wetlands and global climate change: the role of wetland restoration in a changing world.Crossref | GoogleScholarGoogle Scholar |

Georges, A., and Thomson, S. (2010). Diversity of Australasian freshwater turtles, with an annotated synonymy and keys to species. Zootaxa 2496, 1–37.

Gibbons, J. W., Greene, J. L., and Congdon, J. D. (1983). Drought-related responses of aquatic turtle populations. Journal of Herpetology 17, 242–246.
Drought-related responses of aquatic turtle populations.Crossref | GoogleScholarGoogle Scholar |

Kennett, R. M., and Georges, A. (1990). Habitat utilization and its relationship to growth and reproduction of the eastern long-necked turtle, Chelodina longicollis (Testudinata: Chelidae), from Australia. Herpetologica 46, 22–33.

Kingsford, R. T., and Thomas, R. F. (1995). The Macquarie Marshes in arid Australia and their waterbirds: a 50-year history of decline. Environmental Management 19, 867–878.
The Macquarie Marshes in arid Australia and their waterbirds: a 50-year history of decline.Crossref | GoogleScholarGoogle Scholar |

Kingsford, R. T., and Thomas, R. F. (2004). Destruction of wetlands and waterbird populations by dams and irrigation on the Murrumbidgee River in arid Australia. Environmental Management 34, 383–396.
Destruction of wetlands and waterbird populations by dams and irrigation on the Murrumbidgee River in arid Australia.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BD2crkslGmtQ%3D%3D&md5=8db27abc7f1ed59419fc6d84340b2a83CAS |

Kingsford, R. T., Walker, K. F., Lester, R. E., Young, W. J., Fairweather, P. G., Sammut, J., and Geddes, M. C. (2011). A Ramsar wetland in crisis: the Coorong, Lower Lakes and Murray Mouth, Australia. Marine and Freshwater Research 62, 255–265.
A Ramsar wetland in crisis: the Coorong, Lower Lakes and Murray Mouth, Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjsVKksbg%3D&md5=1d29099e7da7543f028b9744bcc4b64cCAS |

Leblanc, M. J., Tregoning, P., Ramillien, G., Tweed, S. O., and Fakes, A. (2009). Basin-scale, integrated observations of the early 21st century multiyear drought in southeast Australia. Water Resources Research 45, W04408.
Basin-scale, integrated observations of the early 21st century multiyear drought in southeast Australia.Crossref | GoogleScholarGoogle Scholar |

Legler, J. M. (1960). A simple and inexpensive device for trapping aquatic turtles. Proceedings of the Utah Academy of Sciences, Arts, and Letters 37, 63–66.

Lindeman, P. V., and Rabe, F. W. (1990). Effect of drought on the western painted turtle, Chrysemys picta belli, in a small wetland ecosystem. Journal of Freshwater Ecology 5, 359–364.
Effect of drought on the western painted turtle, Chrysemys picta belli, in a small wetland ecosystem.Crossref | GoogleScholarGoogle Scholar |

Mitchell, N. J., and Janzen, F. J. (2010). Temperature-dependent sex determination and contemporary climate change. Sexual Development: Genetics, Molecular Biology, Evolution, Endocrinology, Embryology, and Pathology of Sex Determination and Differentiation 4, 129–140.
Temperature-dependent sex determination and contemporary climate change.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BC3c3gtV2ltw%3D%3D&md5=9bfc206f18cbe9dece610e9e5b949cc4CAS |

Palmer, M. A., Liermann, C. A. R., Nilsson, C., Flörke, M., Alcamo, J., Lake, P. S., and Bond, N. (2008). Climate change and the world’s river basins: anticipating management options. Frontiers in Ecology and the Environment 6, 81–89.
Climate change and the world’s river basins: anticipating management options.Crossref | GoogleScholarGoogle Scholar |

Parmesan, C. (2006). Ecological and evolutionary responses to recent climate change. Annual Review of Ecology Evolution and Systematics 37, 637–669.
Ecological and evolutionary responses to recent climate change.Crossref | GoogleScholarGoogle Scholar |

Pittock, J., and Connell, D. (2010). Australia demonstrates the planet’s future: water and climate in the Murray–Darling Basin. International Journal of Water Resources Development 26, 561–578.
Australia demonstrates the planet’s future: water and climate in the Murray–Darling Basin.Crossref | GoogleScholarGoogle Scholar |

Pittock, J., and Finlayson, C. M. (2011). Australia’s Murray–Darling Basin: freshwater ecosystem conservation options in an era of climate change. Marine and Freshwater Research 62, 232–243.
Australia’s Murray–Darling Basin: freshwater ecosystem conservation options in an era of climate change.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjsVKksbo%3D&md5=ccf6ad98ccb72a3243cc3ede066ffab7CAS |

Potter, N. J., Chiew, F. H. S., and Frost, A. J. (2010). An assessment of the severity of recent reductions in rainfall and runoff in the Murray–Darling Basin. Journal of Hydrology (Amsterdam) 381, 52–64.
An assessment of the severity of recent reductions in rainfall and runoff in the Murray–Darling Basin.Crossref | GoogleScholarGoogle Scholar |

Ream, C., and Ream, R. (1966). The influence of sampling methods on the estimation of population structure in painted turtles. American Midland Naturalist 75, 325–338.
The influence of sampling methods on the estimation of population structure in painted turtles.Crossref | GoogleScholarGoogle Scholar |

Rees, M., Roe, J. H., and Georges, A. (2009). Life in the suburbs: behavior and survival of a freshwater turtle in response to drought and urbanization. Biological Conservation 142, 3172–3181.
Life in the suburbs: behavior and survival of a freshwater turtle in response to drought and urbanization.Crossref | GoogleScholarGoogle Scholar |

Roe, J. H. (2008). Chelodina longicollis (eastern long-necked turtle) drinking behavior. Herpetological Review 39, 212–213.

Roe, J. H., and Georges, A. (2007). Heterogeneous wetland complexes, buffer zones, and travel corridors: landscape management for freshwater reptiles. Biological Conservation 135, 67–76.
Heterogeneous wetland complexes, buffer zones, and travel corridors: landscape management for freshwater reptiles.Crossref | GoogleScholarGoogle Scholar |

Roe, J. H., and Georges, A. (2008a). Maintenance of variable responses for coping with wetland drying in freshwater turtles. Ecology 89, 485–494.
Maintenance of variable responses for coping with wetland drying in freshwater turtles.Crossref | GoogleScholarGoogle Scholar |

Roe, J. H., and Georges, A. (2008b). Terrestrial activity, movements and spatial ecology of an Australian freshwater turtle, Chelodina longicollis, in a temporally dynamic wetland system. Austral Ecology 33, 1045–1056.
Terrestrial activity, movements and spatial ecology of an Australian freshwater turtle, Chelodina longicollis, in a temporally dynamic wetland system.Crossref | GoogleScholarGoogle Scholar |

Roe, J., and Georges, A. (2010). Responses of freshwater turtles to drought: the past, present and implications for future climate change in Australia. In ‘Meltdown: Climate Change, Natural Disasters and other Catastrophes – Fears and Concerns for the Future’. (Ed. K. Gow.) pp. 175–190. (Nova Science Publishers: New York.)

Roe, J. H., Georges, A., and Green, B. (2008). Energy and water flux during terrestrial estivation and overland movement in a freshwater turtle. Physiological and Biochemical Zoology 81, 570–583.
Energy and water flux during terrestrial estivation and overland movement in a freshwater turtle.Crossref | GoogleScholarGoogle Scholar |

Roe, J. H., Brinton, A. C., and Georges, A. (2009). Temporal and spatial variation in landscape connectivity for a freshwater turtle in a temporally dynamic wetland system. Ecological Applications 19, 1288–1299.
Temporal and spatial variation in landscape connectivity for a freshwater turtle in a temporally dynamic wetland system.Crossref | GoogleScholarGoogle Scholar |

Smith, I., and Chandler, E. (2010). Refining rainfall projections for the Murray–Darling Basin of south-east Australia – the effect of sampling model results based on performance. Climatic Change 102, 377–393.
Refining rainfall projections for the Murray–Darling Basin of south-east Australia – the effect of sampling model results based on performance.Crossref | GoogleScholarGoogle Scholar |

Spencer, R.-J. (2002a). Experimentally testing nest site selection: fitness trade-offs and predation risk in turtles. Ecology 83, 2136–2144.
Experimentally testing nest site selection: fitness trade-offs and predation risk in turtles.Crossref | GoogleScholarGoogle Scholar |

Spencer, R.-J. (2002b). Growth patterns of two widely distributed freshwater turtles and a comparison of common methods used to estimate age. Australian Journal of Zoology 50, 477–490.
Growth patterns of two widely distributed freshwater turtles and a comparison of common methods used to estimate age.Crossref | GoogleScholarGoogle Scholar |

Spencer, R.-J., and Thompson, M. B. (2003). The significance of predation in nest site selection of turtles: an experimental consideration of macro- and microhabitat preferences. Oikos 102, 592–600.
The significance of predation in nest site selection of turtles: an experimental consideration of macro- and microhabitat preferences.Crossref | GoogleScholarGoogle Scholar |

Spencer, R.-J., and Thompson, M. B. (2005). Experimental analysis of the impact of foxes on freshwater turtle populations. Conservation Biology 19, 845–854.
Experimental analysis of the impact of foxes on freshwater turtle populations.Crossref | GoogleScholarGoogle Scholar |

Spencer, R.-J., Thompson, M. B., and Hume, I. D. (1998). The diet and digestive energetics of an Australian short-necked turtle, Emydura macquarii. Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology 121, 341–349.
The diet and digestive energetics of an Australian short-necked turtle, Emydura macquarii.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaK1M7lslOntQ%3D%3D&md5=5cc8dd9c30c2b4bff9db28a5cf34fac8CAS |

Stott, P. (1987). Terrestrial movements of the freshwater tortoise Chelodina longicollis Shaw as monitored with a spool tracking device. Australian Wildlife Research 14, 559–567.
Terrestrial movements of the freshwater tortoise Chelodina longicollis Shaw as monitored with a spool tracking device.Crossref | GoogleScholarGoogle Scholar |

Thomas, C. D., Franco, A. M. A., and Hill, J. K. (2006). Range retractions and extinction in the face of climate warming. Trends in Ecology & Evolution 21, 415–416.
Range retractions and extinction in the face of climate warming.Crossref | GoogleScholarGoogle Scholar |

Thompson, M. B. (1983). Populations of the Murray River tortoise, Emydura (Chelodina): the effect of egg predation by the red fox, Vulpes vulpes. Australian Wildlife Research 10, 363–371.
Populations of the Murray River tortoise, Emydura (Chelodina): the effect of egg predation by the red fox, Vulpes vulpes.Crossref | GoogleScholarGoogle Scholar |

Thompson, M. B. (1993). Hypothetical considerations of the biomass of chelid tortoises in the River Murray and the possible influences of predation by introduced fox. In ‘Herpetology in Australia’. (Eds D. Lunney and D. Ayers.) pp. 219–224. (Surrey Beatty: Sydney.)

Turtle Conservation Fund (2002). ‘A Global Action Plan for Conservation of Tortoises and Freshwater Turtles. Strategy and Funding Pospectus 2002–2007.’ (Conservation International and Chelonian Research Foundation: Washington, DC.)

Vörösmarty, C. J., McIntyre, P. B., Gessner, M. O., Dudgeon, D., Prusevich, A., Green, P., Glidden, S., Bunn, S. E., Sullivan, C. A., Liermann, C. R., and Davies, P. M. (2010). Global threats to human water security and river biodiversity. Nature 467, 555–561.
Global threats to human water security and river biodiversity.Crossref | GoogleScholarGoogle Scholar |