Bald Eagles, with their distinctive white heads and striking brown bodies, are the symbol of American strength and freedom. But what fuels these powerful birds of prey? What do they feast on to maintain their status as one of the largest birds of prey in North America? In this article, we’ll take a closer look at the diet of Bald Eagles and discover the variety of foods that sustain these magnificent creatures in their natural habitats. From fish to small mammals, we’ll uncover the secrets of the Bald Eagle’s menu and the unique adaptations that make them such successful hunters.
The diet of Bald Eagles
The national bird of the United States of America, Bald Eagles are a large sea eagle species with a widespread distribution throughout North America. They’re found in Canada, the U.S., and northern Mexico. You can find them dwelling in areas with old-growth trees for nesting and large water bodies for food sources.
With their smooth white heads standing in stark contrast with the rest of their chocolate-brown bodies, Bald Eagles are remarkable birds, known to build the largest nests among all North American birds.
Much like other eagle species, Bald Eagles are opportunistic carnivores that have a special preference for fish but wouldn’t hesitate to take a different prey if they can. With as many as 400 different species falling on their diet menu, these eagles rank second in North America in terms of the number of preys, closely following the Red-tailed Hawks (that prey on about 500 species).
To answer your question in brief, Bald Eagles are apex predators and feed on a variety of prey, including fish, waterfowl, and small mammals. Fish make up a large part of the Bald Eagle’s diet and they hunt by diving into the water and snatching their prey with their talons. In addition to fish, they also consume birds, rabbits, squirrels, and other small mammals.
Now, we’ll dig deeper into the diet of Bald Eagles to better understand their prey selection. It will help us discuss their hunting style further in the article. Are you ready to get started?
Fish
The primary food source for all sea eagles, including Bald Eagles, fish are not just preferred by these raptors but also contribute to roughly 60-75% of their total diet throughout their range. In some areas – take Oregon, for instance – fish account for over 90% of their diet.
While Bald Eagles aren’t the only fish-eating birds in North America, the size of fish they prefer is larger than other piscivorous birds. They hunt about 100 different fish species, with the species concentration varying throughout their range.
In the western parts of the continent, salmons and trouts dominate their diet, with Sockeye Salmon, Pink Salmon, and Coho Salmon are most commonly taken in Alaska. The eagles are quite fond of Chinook Salmon as well, but due to its large size, it’s impossible to prey on the living ones.
You can spot these eagles pecking on Chinook Salmon carcasses whenever they find one. In southern Alaska, the eagles also prey on Candlefish, Pacific Herring, and Pacific Sandlance.
In Florida, Bald Eagles mainly hunt catfish like Brown Bullheads, Channel, and Blue Catfish. They’re also known to prey on eels, needlefish, trout, and mullet. In Maine, White Suckers and Chain Pickerels are their primary prey, while in Maryland, they take Threadfin Shad, American Gizzard Shad, and White Bass.
Common Carp, American Chad, and Largescale Suckers dominate the diet of these eagles in Oregon and Nebraska.
Apart from these fish species, others that find their way on a Bald Eagle menu from time to time include Rainbow Trout, Pacific Cod, Rock Greenling, White Catfish, Largemouth Bass, Atka Mackerel, Blue Walleye, Striped Bass, Dogfish Shark, and Northern Pike.
Lastly, these two large fish species are taken by Bald Eagles as carrions: Lemon Shark and Pacific Halibut.
Did you know? Although Bald Eagles both prefer and enjoy hunting fish actively, not all fish in their diet are hunted. Some of them (about 12-18%) are pirated away from other hunting birds, while the others are scavenged on.
Other birds
While a large part of Bald Eagles’ diet is aquatic, another significant part of it is avian; but even a majority of birds preyed upon by them are aquatic in nature. This makes sense since these eagles live around water bodies, where they’re highly likely to encounter waterbirds.
Bald Eagles prey on a wide variety of birds, with about 200 recognized species on their radar. Their ideal avian prey are Mallards, American Coots, and Western Grebes; they’re just the right size for the eagles to fly away with and, thus, most commonly hunted.
In the coastal areas of Maine, the Bald Eagles hunt Common Eiders, Black Ducks, and Double-crested Cormorants. The raptors can also develop more specific taste; for instance, Bald Eagles found on the San Miguel Islands prey solely on Velvet Scoters, while those dwelling around Lake Superior feed almost exclusively on the American Herring Gulls.
In some areas, the eagles are also reported to dig up the burrow nests of nocturnal seabirds like Shearwaters and Storm Petrels and feed on all contents found inside.
Occasionally, Bald Eagles are found preying on larger seabirds like Common Loons, Ross’ Geese, Sandhill Cranes, Great Blue Herons, Canada Geese, Common Murres, Tundra Swans, and Brown Pelicans.
They also tend to attack larger birds like Trumpeter Swans, Whooping Cranes, and American White Pelicans, but with no success. At times, the eagles settle for the fledglings of these birds instead.
Do Bald Eagles prey on other raptors?
Even among the other birds of prey, the Bald Eagles are quite formidable. It is natural to wonder if any of the raptors could be their prey, but the answer is: not really.
While Bald Eagles have killed other raptors on occasion, the attacks usually begin while competing for food. The eagles don’t shy away from outright stealing other raptors’ food, either.
The raptors that have been known to fall prey to Bald Eagles are Screech Owls, Peregrine Falcons, Red-tailed Hawks, Ospreys, Black and Turkey Vultures, and Northern Goshawks.
Small mammals
As you might have observed so far, fish and birds are two major components of a Bald Eagle’s diet. These raptors don’t instinctively go after mammals, not only unless they have a choice. This is why mammals are only known to be hunted by eagles on their wintering grounds, where their food choices are already scarce.
When going for a mammal, Bald Eagles generally prefer those with an established local population to provide them with a consistent food source. In Colorado, their prime target is the White-tailed Jackrabbit. Nutrias, Muskrats, squirrels, Montane voles, Brown rats, and porcupines serve as a secondary diet. In Wyoming, they hunt in pairs for rabbits and prairie dogs.
Among the carnivores, Bald Eagles are found preying on martens, minks, skunks, domestic cats, raccoons, and river otters. Seal colonies are also a significant food source for the eagles.
Reptiles and other prey
If there’s one thing you need to know about Bald Eagles, it’s that they never say no to food. So, while they can easily appease themselves with fish, birds, and mammals, when given an opportunity, they’ll also take reptiles. This is most commonly seen in areas where the reptile population is abundant, such as Florida and Texas.
Among turtles, their major targets are Diamondback terrapins, common musk turtles, softshell turtles, snapping turtles, and map turtles. Occasionally, they’ve also taken Great sirens, southern alligator lizards, garter snakes, and rattlesnakes as prey.
For the last, we’ve saved the most unusual prey of Bald Eagles; the ones you would never have imagined them preying on: invertebrates.
The Bald Eagles found in Alaska seem to have developed a specific taste for water creatures like sea urchins, starfish, abalones, bivalves, land snails, squids, and periwinkle.
How do Bald Eagles hunt for food?
A thought that might have crossed your mind while reading about the diverse range of Bald Eagle preys: these eagles must be skilled hunters.
And indeed, they are. Bald Eagles are gifted in both strength and physical attributes. They have spicules on their talons, just like the Osprey, to enable them to catch fish more easily from the water bodies. Their toes also have rough bumps that prevent slippery fish from slipping out of their grasp.
The sharp claws make for fine flesh-tearers and are equally adept at seizing bird prey mid-air. All these qualities added to their keen eyesight and fast flight, make them the lethal avian hunters that they are, so much so that even other raptors cower from them.
When they begin to hunt, Bald Eagles first find a tall perch near a water body. While flying over a particularly large water body, they might even soar right over, moving in circles to catch a movement beneath. Once they’ve locked the location, they take a swift dive with talons extended, grasp the fish, and are out in no time.
Do Bald Eagles hunt in groups?
While Bald Eagles generally prefer to hunt alone, at times, you might spot a couple working in cooperation. This is usually in the case of large, mostly mammalian prey, such as herons, rabbits, or livestock.
For the eagles, it’s a two-people job where one works as the distractor, and the other seizes the prey. The prey is thereafter equally shared between both parties. However, these partnerships never seem to last long.
Do Bald Eagles need to fight other predators in the wild?
No matter how strong or ruthless Bald Eagles might be, they have plenty of competition for food in the wild, especially for fish. Be it other raptors, corvids, gulls, or mammals like bobcats or coyotes, even domestic cats and dogs; all want a share in the meal.
However, the toughest competitors of Bald Eagles by far remain their own cousins, Golden Eagles. Because the size and strength of these two are roughly equal, a conflict might end either way. Golden Eagles are also known to compete with them for other, particularly avian, prey.
What do baby Bald Eagles eat?
Bald Eagles are early breeders and begin to mate around April and lay between 1-3 eggs by the end of May. Once the eggs have been laid, both parents take turns incubating them; the mother plays a more dominant role here.
Once the eggs have hatched, one of the two parents stays with fledglings all the time while the other brings home food. This goes on for about 5-6 weeks, by the time the eaglets are somewhat capable of looking after their own. During this period, their diet, much like the parents’, is made up largely of fish, which the mother feeds them by tearing them into smaller pieces.
Baby Bald Eagles have huge appetites and grow just as fast. They can gain as much as 170 grams in a single day! By the time they’re eight weeks old, they’ve learned wing flapping and are ready to fly. As is true for most raptors, the oldest is generally the dominant one and is often found to kill other siblings; this happens in the early stages of their growth, probably by the third week.
The nestling might stick around for a week or so but will soon join other juveniles and hunt for themselves. In the beginning, they mostly scavenge on mammal or bird carcasses. But within a year, they’ve mastered the art of hunting on their own.
Related articles: