An assessment of endemism and species richness patterns in the Australian Anura

Abstract

Aim: To assemble a continental-scale data set of all available anuran records and investigate trends in endemism and species richness for the Anura. Location: Continental Australia. Methods: 97,338 records were assembled, covering 75% of the continent. A neighbourhood analysis was applied to recorded locations for each species to measure richness and endemism for each half-degree grid square (c. 50 km) in the continent. This analysis was performed for all anurans, and also for each of the three main anuran families found in Australia. A Monte Carlo simulation was used to test a null hypothesis that observed centres of endemism could result simply from an unstructured overlapping of species ranges of different sizes. Results: Eleven main centres of anuran endemism were identified, the most important being the Wet Tropics and the south-west near Bunbury-Augusta and near Walpole. With the exception of south-western Australia, all of the identified significant endemic centres are in the northern half of the continent. The regions identified as significant for endemism differed from those identified for species richness and are more localized. Species richness is greatest in the Wet Tropics and the Border Ranges. High species richness also occurs in several areas not previously identified along the east and northern coasts. Main conclusions: Weighted endemism provides a new approach for determining significant areas for anuran conservation in Australia and areas can be identified that could be targeted for beneficial conservation gains. Patterns in endemism were found to vary markedly between the three main anuran families, and south-eastern Australia was found to be far less significant than indicated by previous studies. The need for further survey work in inland Australia is highlighted and several priority areas suggested. Our results for species richness remain broadly consistent with trends previously observed for the Australian Anura. © 2007 Commonwealth of Australia.