Artificial water catchments influence wildlife distribution in the Mojave Desert

Abstract

ABSTRACTWater often limits the distribution and productivity of wildlife in arid environments. Consequently, resource managers have constructed artificial water catchments (AWCs) in deserts of the southwestern United States, assuming that additional free water benefits wildlife. We tested this assumption by using data from acoustic and camera trap surveys to determine whether AWCs influenced the distributions of terrestrial mammals (>0.5 kg), birds, and bats in the Mojave Desert, California, USA. We sampled 200 sites in 2016–2017 using camera traps and acoustic recording units, 52 of which had AWCs. We identified detections to the species‐level, and modeled occupancy for each of the 44 species of wildlife photographed or recorded. Artificial water catchments explained spatial variation in occupancy for 8 terrestrial mammals, 4 bats, and 18 bird species. Occupancy of 18 species was strongly and positively associated with AWCs, whereas 1 species (i.e., horned lark [Eremophila alpestris]) was negatively associated. Access to an AWC had a larger influence on species’ distributions than precipitation and slope and was nearly as influential as temperature. In our study area, AWCs functioned as an important influence on wildlife occupancy, which supports the long‐held assumption that AWCs may benefit wildlife in arid habitats. We encourage managers to maintain existing AWCs, particularly those in areas forecasted to have the largest decrease in water availability. We also recommend long‐term, systematic monitoring of AWCs, which will facilitate more informed management decisions. © 2019 The Wildlife Society.