Endemic to California’s arid Central Valley, endangered Blunt-nosed Leopard Lizards (Gambelia sila) have adapted to xeric conditions, but like many desert lizards, remain at-risk to extinction due to climate change. Understanding how G. sila maintains water balance through cutaneous evaporative water loss (CEWL) can help inform endangered reptile conservation strategies in warmer, drier environments. We hypothesized that seasonal changes in climate drives water loss across the skin, and thus hydration for G. sila. To study the lizards’ osmoregulation, we measured CEWL and plasma osmolality of the same induviduals throughout the field season and found great variability in lizard hydration. CEWL, while low, represents a major route of water loss for G. sila, and the large amount of time they spend in comparatively humid rodent burrows may help prevent water loss. As the effects of climate change intensify, megadroughts may increase hydric pressure on G. sila and other sensitive species, so it will be important to identify which habitat features supply the most water—making them integral to survival.