OBSERVING PREDATION PRESSURE ON THE ENDANGERED BLUNT-NOSED LEOPARD LIZARD (GAMBELIA SILA)

Kathryn D Ramirez; California State University, Fresno; k_rami07@mail.fresnostate.edu; Cha Kong Meng Thao, Devon S. Mitchell, Kira N. Gangbin, Keyanna Pinto, Michael Westphal, Andrew C. Kraemer, Rory S. Telemeco

The blunt-nosed leopard lizard (Gambelia sila) is a federal- and state-listed endangered species endemic to the San Joaquin Desert that is on the decline throughout much of its range. Although climate change and habitat destruction are commonly cited reasons for recent declines, increased predation pressure could also contribute. Common ravens (Corvus corax) are a known lizard predator that have greatly increased in abundance in recent decades. We hypothesized that this increase contributed to the recent decline and potential extinction of G. sila on the Panoche Plateau. We tested this hypothesis by deploying clay models color- and size-matched to live G. sila at the Panoche Plateau and a nearby site that has not declined. A subset of models was also paired with camera traps to aid predator identification. We observed attempted predation events from mammalian and avian predators at both sites, but we did not observe any attempted predation from common ravens. The most observed predators were coyotes (Canis latrans) and loggerhead shrikes (Lanius ludovicianus). Altogether, we can further pursue G. sila conservation by observing the effects that predation has on two distinct populations.

Blunt-Nosed Leopard Lizard Captive Breeding Program   Student Paper InPerson Presentation