Bald eagle nest tree locations and productivity protocols for Glacier Bay National Park 1994

Kralovec, M

During the summer of 1994, 183 bald eagle nests were located in Glacier Bay National Park. Of these nests, 60% were occupied, 22% unoccupied, and 18% unknown productivity. Of the occupied nests, 47% were active. Twenty-eight nestling and/or fledgling eagles were counted during the survey. Bald eagle nests were not more concentrated between different sections of Glacier Bay (P = 0.08). Bartlett Cove (n = 10), the Beardslee Islands (n = 23), Geikie Inlet (n = 21), Willoughby Island (n = 8), and Hugh Miller Inlet (n = 9) were areas with large numbers of eagle nests. Ninety-six percent of the nests were located in trees and 4% on the ground or on cliff ledges. Mean nest tree height was 24.3 m, with a mean nest height of 16.3 m. Mean diameter at breast height for all nest trees was 71.9 cm. On the average, nest trees were 35.9 m from the intertidal. Productivity surveys should be conducted using 2 aerial surveys periods. During the first survey each nest should be designated occupied, active, unoccupied or not found. During the second survey all occupied and active nests should be designated successful, failed, or not found, along with the number of young counted. Productivity should be summarized as young per occupied nest, young per active nest, young per successful nest, percent of occupied nests successful, and percent of active nests successful