Bald Eagles

 Resource Brief - March 2009

Importance/Issues

Bald eagles (Haliaeetus leucocephalus) are keystone predators on avian (e.g., seabirds) and fish (e.g., salmon) populations and hence serve an important ecological role in freshwater and marine coastal systems in SWAN parks. Their occurrence and reproductive performance may be influenced by weather conditions, toxic contaminants, food availability, human-related impacts, and climate. Bald eagles may not attempt to nest or their attempt may fail if breeding conditions are unsuitable during a given year. Thus, their nest occupancy and reproductive rates may be useful indicators of both current condition and long-term change (variability) of freshwater and marine coastal systems. KATM, KEFJ, and LACL all contain large breeding populations of bald eagles, and this species is specifically mentioned in enabling legislation for LACL. Bald eagle populations are under continuing threat from human-related impacts such as ecotourism, sport and commercial fishing, timber harvest, potential mining activities adjacent to the parks, and potential oil spills or other accidents along marine coastlines. Further, global climate change will have an unknown effect on their forage base and nesting habitat.

Current and Future Work Efforts

Monitoring for bald eagles for SWAN park units is scheduled for 2010.