Sampling bias in reptile occurrence data for the Kruger National Park

Effective conservation and management of organisms require an understanding of how species are spatially distributed at both broad and fine spatial resolutions, and ideally also the underlying determinants of their distribution patterns (Hurlbert & Jetz 2007; Kery 2011). However, species geographic data that may help inform conservation management decisions are often limited and biased in their collection strategies (Franklin 2010). For example, although museum databases often include occurrence data of collected specimens, the principal purpose of most museum collections is to act as reference catalogues for species identification rather than for species distribution mapping (Newbold 2010). It is important to note that although several museum specimens are collected directly as a result of systematic sampling, many specimens are collected opportunistically (Kadmon, Farber & Danin 2004; Pyke & Ehrlich 2010). As a result, collection effort and spatial coverage within museum data naturally vary depending on the interests of the collection. Despite this, a recently increased urgency in the need for species distribution information has placed a greater emphasis on the use of museum databases for amassing species occurrence records (Syfert, Smith & Coomes 2013).