Identifying thresholds for responses of amphibians to groundwater and rainfall decline
National Climate Change Adaptation Research Facility
Faculty of Health, Engineering and Science
School of Natural Sciences/Centre for Ecosystem Management
Amphibians are key indicators of wetland health and under conditions of hydrological change it is important to be able to predict changes in their diversity and abundance. Here we develop a methodology for predicting how nine amphibian species with different life histories could potentially respond to declining groundwater, and declining rainfall – both of which are occurring on the Gnangara Mound north of Perth in south-western Australia. This example can be considered as ‘data-poor’ because although we had access to data on amphibian assemblages and relative abundance from systematic surveys, we could derive few insights into the environmental drivers of such patterns using multivariate analysis. Instead we turned to amphibian biologists with relevant expertise on Gnangara Mound amphibians to derive conceptual models of the most important factors explaining whether populations would persist or decline under anticipated environmental change. These models were constructed as Bayesian Belief Networks (BBNs) and were developed for each of three reproductive guilds: amphibians that breed in water, amphibians that breed in terrestrial nests that are later flooded, and one entirely terrestrial-breeding species.