Spatial Ecology and Habitat Exploration of Neotropical Migrants during Spring Migratory Stopover

Dave Slager, MS Candidate
Advisor: Paul Rodewald

More than half of all bird species breeding in North America migrate annually to and from Mexico, the Caribbean, Central America, or South America, and many of these Nearctic-Neotropical migrants have declined in population. Recent evidence suggests that a disproportionate amount of annual mortality may occur during migration. Migrant birds spend more time and energy resting and refueling during stopover than they spend making migratory flights, so understanding stopover ecology is essential for effective conservation of migratory birds. Spatial movements of migrants during stopover are poorly known. My research examines the relationships between stopover habitat characteristics and local movement patterns of migrant Yellow-rumped Warblers and Northern Waterthrushes during spring stopover along the Upper Mississippi River. My objectives are to (1) assess local movement patterns of both species during stopover and (2) evaluate the effect of initial stopover habitat suitability on exploratory movements of Northern Waterthrushes. Individual migrants will be mist-netted, radio-tagged, and relocated to predetermined forest patches that differ in forest structure and hydrology. Bird movements, prey availability, and habitat occupied will be monitored for the duration of stopover. This will be one of the first studies to experimentally test the influence of stopover habitat suitability on the movements of Nearctic-Neotropical migrant passerines. This research will provide new information on stopover ecology that will help land managers develop long-term regional plans for conserving habitat for migratory birds.

Funding Sources: US Fish and Wildlife Service and The Ohio State University Graduate School