Annual-Cycle Movement Patterns of Eastern Brown Pelicans (Pelecanus occidentalis carolinensis) from the Northern End of their Breeding Range

Understanding the variability in movement patterns of marine birds throughout their annual cycle is critical to ecosystem-based management in coastal regions. Tracking data from seabirds frequently demonstrates that movement patterns throughout the annual cycle are more complex and extensive than previously thought, and that factors that influence these movements differ throughout the species' range. During May of 2023, we deployed satellite tags on Eastern Brown Pelicans (Pelecanus occidentalis carolinensis) breeding in the Chesapeake Bay region, an area that supports commercial fisheries for forage fish, offshore energy production, and lies at the northern end of the species' breeding range. During the breeding season pelicans foraged throughout Chesapeake Bay and along the Atlantic coast up to 75 km from the breeding colony. Interannual shifts in use areas were linked to colony switching. Post-breeding, pelicans consistently staged in the mid-Chesapeake Bay before southward migration. Wintering locations extended from the Chesapeake Bay to Cuba. The study demonstrates that pelicans breeding in the Chesapeake Bay region exhibit high variability in movement patterns within and outside of the breeding season. Therefore, marine spatial plans within and beyond the Chesapeake region may need to account for intra-population variability in movement patterns to ensure long-term success.