The persistence of threatened species in California is in part the result of head-starting programs of local institutions and partnerships. Given increasingly limited resources, small teams of conservation professionals must optimize growth and survival of head-starts throughout development in captivity, as well as consider the environment into which these animals will be released—more uncertain and dynamic now than ever. Here, we present on San Francisco Zoo and Yosemite National Park’s project to rear threatened California Red-legged Frogs (Rana draytonii) for release in Yosemite. We consider both behavior and disease susceptibility in our efforts to raise frogs best suited for the wild.