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Effects of Wetland Water Source on a Population of the Australian Eastern Long-Necked Turtle Chelodina longicollis

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Abstract

This study investigates the impacts on the Australian native eastern long-necked turtle Chelodina longicollis of wetland waters derived from (1) precipitation and groundwater flow and wetlands also supplemented with (2) irrigation runoff from agricultural lands, (3) tertiary-treated sewage effluent and (4) harvested stormwater. Influences of water quality parameters on population attributes of the turtle population are considered. A total of 951 C. longicollis were captured in a mark-recapture study over 8 months. Overall, a female sex ratio bias was observed, and a larger number of smaller turtles were found in wetlands not contaminated by recycled tertiary-treated effluent. Dissolved oxygen, temperature, surface area and emergent vegetation had the greatest impact on turtle population structure. The lower the dissolved oxygen, the smaller the surface area of the wetland, and the higher the percentage of emergent vegetation, the greater the number of juveniles present. Water quality parameters which would be detrimental to fish predators appear to provide a ‘safe haven’ for juvenile turtles at the most vulnerable life stage of turtles.

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Acknowledgments

Volunteers, especially Geoff and Judy Ryan, and Josh Newman, supported fieldwork. Funding was provided from an Australian Postgraduate Award, F. G. Swain Award, and the University of Western Sydney Research Training Scheme (MR) and College Postdoctoral Fellowship (I.W). David Hall of Hallprint Fish Tags provided shellfish tags to mark turtles. Research was undertaken under New South Wales National Parks and Wildlife Scientific Collection Permit Number 12344, New South Wales Department of Primary Industries Permit P07/0066-3.1 and University of Western Sydney Animal Research and Training Protocol 07/020.

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Ryan, M.M., Burgin, S. & Wright, I. Effects of Wetland Water Source on a Population of the Australian Eastern Long-Necked Turtle Chelodina longicollis . Water Air Soil Pollut 226, 408 (2015). https://doi.org/10.1007/s11270-015-2658-1

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