Distribution, Ecology, Disease and Physiology of a Mountain-Top Endemic Frog in the Face of Climate Change: A Study on Philoria loveridgei

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Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
Evidence clearly shows that climate change has affected ecosystems and individual species, challenging species survival and increasing extinction rates. Assessing species vulnerability to climate change is a key topic in ecology and conservation biology. Uncertainty remains as to which species will be most vulnerable and to what extent. An integrative framework has been developed to guide research towards evaluating species vulnerability. This approach proposes that a species’ vulnerability to climate change is dependent upon the synergistic combination of intrinsic (sensitivity) and extrinsic (exposure) factors. Following this framework, I examined how (i) sensitivity to environmental change (i.e. changes in calling phenology, thermal tolerances, and disease susceptibility) and (ii) exposure to environmental change (i.e. detectability, occupancy and species distribution, and thermal environment and microhabitat buffering) influenced the vulnerability of Philoria loveridgei, a direct-developing anuran, in subtropical rainforests of mid-eastern Australia. This allowed me to evaluate the vulnerability of this species to climate change. Sensitivity results indicated that calling phenology and breeding phenology of P. loveridgei were influenced primarily by the spring and early summer rainfall events associated with the start of the calling season. I hypothesise that these rainfall events increase soil moisture, and hence increase P. loveridgei nest moisture and subsequently forming a suitable environment for egg and larval survival. These early summer rainfall events would therefore cue the onset of the calling, associated with breeding. A diurnal calling pattern was identified for P. loveridgei, with a higher calling frequency during the early morning hours.