The population structure and age-related behaviour of the northern bald eagle (Haliaeetus leucocephalus alascanus Townsend) at a winter feeding site in Nova Scotia

The population structure and age-related behaviour of wintering Northern Bald Eagles (Haliaeetus leucocephalus alascanus Townsend) were studied in the Gaspereau Valley, Kings Co., Nova Scotia from January 8 to March 7, 1979. Using five ages of eagles, nopulation fluctuations were recorded. A prominence of immature eagles was noted early in the winter, while older birds increased in numbers towards the end of the study period. Age-related differences in general maintenance activities, feeding behaviour, intraspecific behaviour (such as vocalization) and interspecific behaviour were determined. These differences permit birds of all ages to effectively feed at the feeding site simultaneously. The balance of innate to learned responses decreased with increasing age.