Welcome to the American Ornithological Society 2018 Annual Conference. We are pleased to have you join us at the lovely Hilton El Conquistador Resort in Tucson, AZ.
Grassland passerines are among the most rapidly declining birds in North America. Baird's and Grasshopper Sparrows are part of this declining guild, and are at risk due to habitat loss and degradation on both their breeding grounds in the Northern Great Plains and their wintering grounds in the Chihuahuan Desert of Mexico and southwestern US. Conversion of grassland areas to agriculture combined with poor grazing practices on the areas that remain have resulted in particular habitat damage in Mexican rangelands, which may be limiting these populations more than conditions on their breeding grounds. We combined adult survival data for both species with remotely sensed habitat data collected via Unmanned Aircraft Systems to identify A) where in their annual cycle birds are most limited and B) what habitat characteristics drive differences in survival on the breeding and wintering grounds. We are also using connectivity information collected via light-level geolocators to connect populations and identify potential stopover areas and corridors used by Baird's and Grasshopper Sparrows in the NGP. We found that adult survival is comparatively high and invariant on the breeding grounds across years but varies widely on the wintering grounds. We explore and discuss the effects of shrub density, height, and volume on adult survival and discuss our plan to combine these data with nest and juvenile survival data in the Northern Great Plains into an integrated population model to efficiently identify areas of conservation need within the annual cycle of these two species.
