Abstracts

Presented by Kelsey Navarre - Email: kelsey.navarre@colostate.edu

The continental population of scaup remains well below population objectives. Previous analyses of long-term demographic data have revealed recruitment as the likely driver of population decline. Recruitment is comprised of several potentially important vital rates, which are often assumed to be independent in population models. This assumption could be costly because covariation in vital rates can sometimes have a greater influence on population dynamics than variation in any vital rate on its own. Long-term monitoring of lesser scaup (Aythya affinis) at Red Rock Lakes National Wildlife Refuge allows us to study temporal covariation in vital rates. This unique study has collected data across the annual life cycle of lesser scaup, including breeding propensity, clutch size, nesting success, duckling survival, post-fledging juvenile survival, and seasonal survival of adults. We examined the effects of hydrological variation on variation and covariation of vital rates, and the consequences of such (co)variation on population dynamics of the local lesser scaup population. Our results provide key insights into the life-history responses of lesser scaup to changes in wetland habitat conditions. Given that both climate and land-use change can drastically alter wetland hydrology, our work could guide similar studies on wetland habitat management and landscape conservation for lesser scaup amidst ongoing global change.