Migration, home range, and important use areas of Florida sub-adult bald eagles

Abstract

Long distance movements of Bald Eagles (Haliaeetus leucocephalus) have prevented a thorough documentation of their migration when monitored with traditional methods of banding and radio telemetry. I used satellite telemetry to determine diurnal and nocturnal important use areas (IUAs), migration routes, stopover sites, and home ranges of 69 migratory and non-migratory Florida sub-adult Bald Eagles. I located 151 daytime IUAs in 20 states and provinces, and 50 nocturnal roosts in 8 states and provinces. There was no difference in coarse home range size of migratory eagles between sexes in winter or summer (2-way ANOVA sex x season). Coarse home ranges were larger in winter ( x = 25,218 km2, 95% CI: 13,015 ? 37,421) than summer ( x = 6,166 km2, 95% CI: 2,696 ? 9,637; F1,64 = 4.03, P = 0.01). Eagles made equal use of Coastal Plain (n = 24) and Appalachian Mountain (n = 26) migratory routes during the first migration north. I recommend conserving nocturnal roosts and undeveloped shoreline forest within IUAs for sustained recruitment of Florida Bald Eagles.