The Bald Eagle, a large North American raptor and national symbol, is known for its opportunistic and flexible diet rather than strict specialization. Although the primary source of nutrition is aquatic, bald eagles consume a wide variety of prey, including other avian species. This adaptability allows them to thrive across diverse habitats, from coastal regions to inland rivers and lakes. They are highly resourceful predators that take advantage of nearly any available food source.
The Foundation of the Bald Eagle Diet
Fish form the staple and most significant part of the bald eagle’s diet. In many coastal and riparian populations, fish can account for 66% to over 90% of the total food consumed. This reliance explains why eagles are almost always found near large bodies of water, such as estuaries, major rivers, and seacoasts, where prey is abundant.
The species of fish consumed varies regionally, including common species such as trout, salmon, and carp. Eagles typically catch fish by swooping down and snatching them from the water’s surface using their powerful talons. Their feet are adapted for this task, possessing rough projections called spicules that help them grip slippery prey.
Avian Prey: Targeting Other Birds
Bald eagles actively prey on other birds, confirming their role as avian predators. Waterfowl are the most commonly targeted group due to habitat overlap and size. Species like ducks, geese, and coots are regularly taken, especially during winter when fish access is limited by frozen water.
Predation often targets individuals that are young, sick, or injured, making them easier to catch. Eagles also raid the nests of colonial nesting birds, such as gulls, herons, and egrets. During these raids, they consume eggs and nestlings, providing a concentrated, high-protein food source during the breeding season.
The frequency of bird consumption increases when primary food sources are scarce, highlighting the eagle’s adaptability. Eagles in wintering areas pursue ducks and seabirds when ice restricts access to fish. Active pursuit of healthy, adult waterfowl also occurs, with the eagle attacking prey in the air or forcing it onto the water.
Hunting Strategies and Opportunism
Beyond active hunting, bald eagles employ diverse strategies to secure meals, underscoring their opportunistic nature. Scavenging is frequent, with eagles readily consuming carrion, including roadkill and the remains of larger animals. Consuming dead matter provides a reliable food source when live prey is difficult to acquire.
A notable behavior is kleptoparasitism, the act of stealing food from other animals. Eagles frequently harass smaller raptors, such as Ospreys, forcing them to drop fish they have just caught, which the eagle then retrieves. They also steal from gulls and other birds that have secured a meal. This method is an efficient way to acquire food without expending energy or risking injury associated with a live hunt.
Foraging techniques change with age, as younger, less experienced eagles rely more heavily on scavenging and kleptoparasitism. Adult eagles, having honed their hunting skills, show a higher success rate in actively pursuing and catching live prey. This spectrum of feeding methods defines the bald eagle’s ecological success.