Effects of habitat modification on Elseya stirlingi turtle populations in the North Johnstone River
Liliane E. Dethier
May 12, 2010
Department or Program
Elseya stirlingi (Johnstone River snapping turtle) is a little-studied species restricted to the Johnstone River catchment of Queensland, Australia. Half the catchment’s old-growth rainforest has been cleared and riparian zones have suffered from the impact. For these reasons, the Queensland Parks and Wildlife Service has listed E. stirlingi as a high priority species. My first goal was to address two hypotheses derived from previous studies : (1) riparian habitat modification results in less stable turtle populations and (2) turtles prefer logs over other microhabitats. Although I did not find relationships between habitat modification and population density or sex ratio, I found fewer young turtles at more disturbed sites than at less disturbed sites, supporting my first hypothesis. I also found more turtles on logs than expected if turtles were distributed randomly among microhabitats. My second goal was to describe new natural history data about E. stirlingi depth and substrate preferences. Follow-up studies should build on these results to more conclusively determine this species’ conservation status.