Spatial and temporal interactions between top carnivores at water sources in two deserts of western North America

Abstract Climate change is predicted to decrease the availability of water in deserts, potentially increasing competition for water. We wanted to determine if competition between top carnivores in deserts of western North America (i.e., coyote (Canis latrans) and bobcat (Lynx rufus)) was influenced by water availability. Evidence suggests that coyotes and bobcats do not compete for water in the Chihuahuan Desert, but this desert receives 2–3X more precipitation when water is limiting than other western deserts. If water availability influences competition, we predicted that bobcats (subordinate to coyotes) would avoid water sources used by coyotes in deserts where water availability is low when demand is high. We monitored 105 water sources for three years in the Great Basin and Mojave Deserts and captured 810 bobcat visits and 2247 coyote visits. We found no evidence that bobcats avoided water sources used by coyotes. In contrast, bobcat visitation to water increased as coyote visitation increased. It does not appear that bobcats and coyotes compete for water, spatially or temporally (on an hourly scale), in the Great Basin and Mojave Deserts. Our study suggests that anthropogenic water sources may alleviate the effects of environmental water loss on the interactions between top mammalian carnivores.