Datasets / Adak bald eagle study: 1983 progress report


Adak bald eagle study: 1983 progress report

Published By US Fish and Wildlife Service, Department of the Interior

Issued over 9 years ago

US
beta

Summary

Type of release
a one-off release of a single dataset

Data Licence
Not Applicable

Content Licence
Creative Commons CCZero

Verification
automatically awarded

Description

Population composition and movements were monitored through routine vehicle, boat and dump surveys and by eagle banding operations in the winter and summer. Nest surveys in a sample area throughout the breeding season provided egg and production nesting counts. Eagle carcasses, usually from birds electrocuted on naval Station power lines, provide measurement data which can be correlated to sex through necropsy. Eagle visitation to Naval Station appears to correspond to seasonal phenomenon, peaking in winter and summer, and decreasing in the fall and spring. Production figures from the sample area are 2.07 eggs per active nest, and 0.813 nestlings per active nest, indicating a stable eagle population. Insufficient data precluded the determination of new measurement criterion, but the tarsal width and mandible length criterion established last year still appear to be valid indications of sex. A more efficient means of capturing eagles for banding and subsequently sighting them would be useful. Production figures from the sample area indicate a stable eagle population. More data must be collected before any new measurements yield correlative figures.