Bird Migration through an Urban Landscape: Stopover Site Selection, Associations with Native and Non-native Plants, and Stress hormone levels
Migratory animals such as birds are unique in that they change location over the course of their annual cycle in response to variation in weather and food availability. Many passerine bird species migrate between breeding and wintering grounds. Though flight is a relatively efficient method of travel, stopovers are necessary for migrating birds to rest, rehydrate, and replenish fat stores and muscle protein. With increasing urbanization, migrating birds likely pass through and often have to find stopover sites in urban landscapes. In this dissertation, I investigated several potential challenges that migratory birds face as they navigate urban landscapes. These challenges include fewer suitable options for stopover sites, the presence of non-native plants at stopover sites, and stressors associated with urbanization. If human population and road densities in urban landscapes differ in their intensity of disturbance and effects on stopover ecology, then migratory birds at an urban site with higher surrounding human population and road density might show differences in stopover ecology than migratory birds at an urban site with lower surrounding human population and road density. However, I found no consistent relationship between stopover sites and several measures of stopover ecology, including correlations between flying migrants and birds at a site, bird associations with native and non-native plants during migratory stopovers, and corticosterone levels of birds during migratory stopovers. In this dissertation, I discuss possible explanations for these results as well as implications for conservation of migratory birds in urban landscapes.
Bricklin, Rachel Bryna, "Bird Migration through an Urban Landscape: Stopover Site Selection, Associations with Native and Non-native Plants, and Stress hormone levels" (2016). ETD Collection for Fordham University. AAI10125235.