Compensating for diminishing natural water: Predicting the impacts of water development on summer habitat of desert bighorn sheep

Habitat use by a desert ungulate: Predicting effects of water availability on mountain sheep

“…Our modeling exercise, however, allowed us to ''manipulate'' the availability of water in seven mountain ranges, and to make predictions about the influences of those manipulations on habitat quality for mountain sheep. Longshore et al (2009) used similar models to demonstrate the impacts of loss of water sources on the availability of habitat suitable for mountain sheep and, consistent with our results, those authors verified the importance of wildlife water developments to mountain sheep in Joshua Tree National Park, USA.…”

“…Provision of water sources remains controversial (Bleich, 2005;Krausman et al, 2006), and manipulative experiments (Cain et al, 2008) have produced only equivocal results, largely a result of the vagaries characteristic of arid climates. Nonetheless, those concerned with the conservation of mountain sheep must decide how to maintain population size, habitats, and connectivity (Longshore et al, 2009), factors that are critically important to the persistence of that taxon (Bleich, 2006). Recent models (Longshore et al, 2009; this study) provide compelling evidence that reliable water sources are important factors defining habitat quality for mountain sheep inhabiting desert environments, and that they can play pivotal roles in population persistence.…”

“…Nonetheless, those concerned with the conservation of mountain sheep must decide how to maintain population size, habitats, and connectivity (Longshore et al, 2009), factors that are critically important to the persistence of that taxon (Bleich, 2006). Recent models (Longshore et al, 2009; this study) provide compelling evidence that reliable water sources are important factors defining habitat quality for mountain sheep inhabiting desert environments, and that they can play pivotal roles in population persistence. We conclude that provision of water sources can increase the proportion of high quality habitat available to mountain sheep inhabiting hot, arid ecosystems, and that the technique has important implications for population persistence and conservation for those specialized ungulates, even in the absence of per capita increases in nutrient availability.…”

Spatial distributions and resource selection by mule deer in an arid environment: Responses to provision of water

“…Sonoran pronghorn (Antilocapra americana sonoriensis) foraging in the eastern third of the Cabeza Prieta National Wildlife Refuge could not meet their water requirements through use of forage without the use of freestanding water, especially during drought (Fox et al, 2000). Turner (1973) demonstrated that water content of diets of desert bighorn sheep (Ovis canadensis nelsoni) in the western Sonoran desert was insufficient to meet evaporative water losses during the hot-dry season; therefore, that population relied on sources of free water to maintain water balance (Longshore et al, 2009;Bleich et al, 1992). Loss of water sources also reduced critically important habitat for another population of desert bighorn sheep in Joshua Tree National Park, which was partially mitigated by the addition of water developments (Longshore et al, 2009).…”

“…Turner (1973) demonstrated that water content of diets of desert bighorn sheep (Ovis canadensis nelsoni) in the western Sonoran desert was insufficient to meet evaporative water losses during the hot-dry season; therefore, that population relied on sources of free water to maintain water balance (Longshore et al, 2009;Bleich et al, 1992). Loss of water sources also reduced critically important habitat for another population of desert bighorn sheep in Joshua Tree National Park, which was partially mitigated by the addition of water developments (Longshore et al, 2009). Whether species of large mammals are able to meet water demands with preformed or metabolic water is unclear, especially during hot dry seasons, which often correspond with low moisture in forage and increased water demands necessary to support lactation (Cain et al, 2006;Larsen et al, 2012).…”