Reconstruction of the historical range alters niche estimates in an endangered rodent

Defining historical baselines is critical for species conservation. Under the niche reduction hypothesis, species in decline may be restricted disproportionately from parts of their environmental niche. This bias likely has important implications for modeling species’ distributions if only contemporary occurrences (i.e. post‐range reduction) are used, because suitable habitat will be classified as unsuitable. Unfortunately, robust historical occurrence data is rarely available for sensitive species. In this study, we documented historical locations of the endangered, keystone giant kangaroo rat Dipodomys ingens by examining aerial imagery for burrow mounds. These burrow mounds are readily identifiable and distinguishable from other soil disturbances. We found giant kangaroo rat burrows well outside the currently accepted estimate of their historical distribution. Following the niche reduction hypothesis, we found that giant kangaroo rats have been extirpated from the flattest, hottest, ...