Meeting Abstract
Three sympatric lizard species, all largely insectivorous, are syntopic in the northern Great Basin desert scrub, but they differ in their food acquisition modes and the primary prey they consume. The year-to-year variation in precipitation and temperatures, and the resulting prey availability are expected to affect the annual variation in daily food intake and body condition of each species. Based on prior research, the western whiptail lizard, Aspidoscelis tigris, as an intensive, wide forager was hypothesized to maintain a relatively uncompromised body condition and should have a high daily food intake even in years of relatively low arthropod availability. In contrast, body condition and feeding rate in the blunt-nose leopard lizard, Gambelia wislizenii, which is an ambusher, were expected to be more sensitive to climate variation and prey availability. The desert horned lizard Phrynosoma platyrhinos, a myrmecophilic trapline-forager which moves among ant colonies, also was expected to maintain feeding rate and body condition at an overall high level among years, given the abundance and diversity of ants on site. The consequence of the among year variation in body condition should be similarly varying in number of young recruited into the population the next year. Outcomes were largely as predicted, but more detailed temporal analyses of female energetics and hatchling survivorship would be revealing.
