I evaluated bald eagle (Haliaeetus leucocephalus) population parameters and human disturbance at 3 reservoirs within the Lake Almanor area (sensu U. S. Fish and Wildlife Service [1986]). I evaluated sources of human disturbance and bald eagle nest populations, reproduction, and nest locations, to assess whether human activities were detrimentally affecting eagles. Eagle populations were characterized by population size and rate of growth during 1988-2006 at reservoirs with different levels of human development. I examined territory age, nest occupancy, nesting success, and productivity of recent nests (1997-2006) in relation to the distance of nests from human disturbance sources, including: high-use paved roads, residences, and highly developed areas. The known eagle population increased by 67% (from 9 to 15 pairs) between the 1980s and 2006 and has met the Recovery Plan objective. Most of the population increase occurred at Lake Almanor, the largest and most developed reservoir. A high proportion of nests within newer territories were closer to sources of human disturbance than are older nests. Average nesting success and productivity was equal or higher for nest territories closer to human facilities than for those farther away. Eagles at newer territories were more successful and productive than pairs at older territories. Several recently established territories showed substantial tolerance of human activity close to nest sites. Overall, the population shows no indications of being detrimentally affected by human disturbance. The establishment of new territories in areas closer to human disturbance sources, and the higher reproductive success of these nests, suggests that these territories are high quality habitat and that the population as a whole is developing greater tolerance for human disturbance. Many newer nests are located closer to sources of disturbance than the recent standard prescribed buffer for eagle nests but farther away than new national nest protection guidelines, suggesting that nest protection efforts should incorporate recent local information.
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