5 Turtles of Cooper Creek life in the slow lane 61 animals (Kingsford et al. 2014) as well as cattle (see Chapters 10 and 11). Native fish species cope with this episodic flooding, breeding in large numbers during boom periods and then dispersing across the floodplains (see Chapters 3 and 4). Waterbirds also capitalise on the large feeding areas created by the floods before congregating on lakes in the Lake Eyre Basin or other wetlands in Australia (Kingsford et al. 1999). The freshwater turtles of the Cooper Creek employ different strategies. They can live for a long time (likely more than 100 years, though hard data are difficult to obtain), with their low metabolism and energy needs, allowing them to wait out bleak dry periods. Their success in this difficult environment depends on food delivered by flows into the Cooper waterholes when the river ‘runs’. These ‘in between’ (Bunn et al. 2006) flows sustain the waterholes, allowing some to persist, even in the dry times, and then colonising waterholes which may dry out after breeding in the boom times. Abstraction of water from the rivers of the Lake Eyre Basin could have devastating consequences on the Cooper Creek turtle. The eastern long- necked turtle is less susceptible but still threatened. For Cooper Creek turtles, diversion of water from the river may push permanent waterholes to dry out, even if small flows are taken out (Bunn et al. 2006). The impacts on turtle populations would be devastating. The climax populations could become locally extinct, not only removing them from the river but also halting the ability of these stable populations to provide juveniles to the waterholes along the Cooper. Ultimately, there could be thresholds exceeded, which might threaten the species with extinction. The key message is that these animals depend on flows all of them. It is the timing and frequency of river runs, as well as the frequency, extent and duration of major floods and how these floods spread across the floodplain which is critical. Alteration of flows through deliberate or inadvertent water diversion will be catastrophic for Cooper Creek turtles. Conclusion It is critical to ensure that natural flow regimes are maintained in this incredibly important river system. References Bowden R, Paitz RT, Janzen FJ (2011) The ontogeny of postmaturation resource allocation in turtles. Physiological and Biochemical Zoology 84, 204–211. doi:10.1086/658292 Bunn SE, Thoms MC, Hamilton SK, Capon SJ (2006) Flow variability in dryland rivers: boom, bust and the bits in between. River Research and Applications 22, 179–186. doi:10.1002/rra.904 Chessman BC (1986) Diet of the Murray turtle, Emydura-Macquarii (Gray)(Testudines, Chelidae). Wildlife Research 13, 65–69. doi:10.1071/WR9860065 Georges A (1985) Reproduction and reduced body size of reptiles in unproductive insular environments. In Biology of Australasian Frogs and Reptiles. (Eds G Grigg, R Shine and H Ehmann) pp. 311–318. Surrey Beatty & Sons, Sydney. Georges A, Norris R, Wensing L (1986) Diet of the eastern long-necked tortoise, Chelodina longicollis, from the coastal dune lakes of the Jervis Bay Nature Reserves. Australian Wildlife Research 13, 301–308. doi:10.1071/WR9860301 Georges A, Guarino F, White M (2006) Sex-ratio bias across populations of a freshwater turtle (Testudines:Chelidae) with genotypic sex determination. Wildlife Research 33, 475–480. doi:10.1071/WR06047 Graham T, Georges A, Mcelhinney N (1996) Terrestrial orientation by the eastern long-necked turtle, Chelodina longicollis, from Australia. Journal of Herpetology 30, 467–477. doi:10.2307/1565689
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