Exploring the relationship between sampling efficiency and short-range endemism for groundwater fauna

1. Identifying the existence of short or narrow range endemic species is an important issue when planning for conservation of groundwater fauna in the face of threats to groundwater quantity and quality. 2. Fourteen bores were sampled six times over 3 or 4 years to assess the reliability of net-hauling sampling in broad-scale survey to collect the groundwater fauna present at a site and to identify short-range endemic (SRE) species. 3. Species accumulation curves suggested that one sample from a bore collected 23 % and 46 % of species occurring in low and high abundance, respectively, and two samples collected 38 % and 65 % of such species. False-negative rates provided a slightly higher estimate of the collection probability of species with low abundances. 4. The frequent failure to collect species present at a site means that some apparent short-range endemism was probably an artefact of low sampling effort. Nevertheless, as is typical for subterranean fauna, a high proportion of the known species in the Pilbara region appeared to be SREs. About 55 % had probable ranges <10 000 km2, the criterion proposed by Harvey (2002) for short-range endemism