Accounting for detectability when surveying for rare or declining reptiles: Turning rocks to find the Grassland Earless Dragon in Australia

Abstract

Reptiles are in global decline with nearly 20% of species currently threatened with extinction. Despite these alarming trends, data documenting detailed changes in reptile populations remain sparse and the methods for detecting those changes are largely unevaluated. Rock turning is one commonly used method for detecting the presence or absence of reptiles. Here, we use data from four years of rock turning surveys for the endangered Tympanocryptis pinguicolla to estimate the probability of species occurrence while accounting for detectability. Our data set was zero-inflated with only 36 detections despite some 69,146 detection attempts (rocks turned) across 60 sites. Our analysis revealed the..