Large and in Charge: Bald Eagles in Washington

Adult Bald Eagle| Pedro Rodriguez | NextGen councilmember 

by Wren Wagenbach, NextGen Councilmember

Eagles can be very exciting to spot while birding because of their impressive size. In fact, they are the largest members of the raptor family (a group that includes hawks, falcons, kestrels, owls, vultures, harriers, kites, and osprey!) In North America, we have two native eagle species and in Washington state we are lucky enough to be able to find both of them. The Bald Eagle, which is the most widespread eagle in Washington, and the Golden Eagle, which is even larger, but more commonly found away from urban areas. 

Bald Eagles are considered sea birds because they are tied to wetlands and seacoasts—areas with abundant fish. They prefer to perch in the stands of mature or old growth trees (or tall telephone poles) near water so they have good visibility when hunting for prey. They also use tall trees for nesting, and Bald Eagle nests are huge! The largest nest on record was about 10ft in diameter and almost 20ft tall! While immature eagles spend the first few years of their lives exploring vast swaths of territory, when they form pairs and mate the couple will build their aerie from sticks and twigs and reuse it from year to year (making renovations and expansions when necessary). 

When you spot Bald Eagles around town, it’s likely that you might watch them being scolded and chased by smaller birds or crows. This is because while eagles predominantly eat fish, amphibians, crabs, and small mammals they are not above snatching up other birds or their young. They also frequently engage in kleptoparasitism, a feeding behavior where they harass other birds until they are forced to drop their catch of fish. So, while eagles are striking and impressive birds, their tendency towards playing the big bully of the bird world makes it understandable that they would be subjected to a fair bit of teasing as well. 

Adult Bald Eagles are easy to identify, with their white heads and tails and characteristic large, broad wings that are built for soaring. However, distinguishing between immature Golden Eagles (GOEA) and juvenile Bald Eagles (BAEA) can be difficult as seen in the images below. You can see the similarities between the Bald Eagle (left photo) and the Golden Eagle (right photo.) When you spot the birds soaring outside, some key identification clues are that the Bald Eagle head will appear much larger and jut out from the wings. Immature GOEAs will have white on their outer flight feathers, the “wrist area”, while BAEAs typically have white axillaries (armpits). GOEAs will also only have white feathers at the base of their tail while BAEAs can have a smattering of white throughout

Bald Eagles also vocalize a lot, especially during breeding and nesting season, but for such a big bird they don’t have the most impressive calls. Adults make a series of thin, scratchy whistling notes and screeches, surprisingly high pitched and nasally. It seems that the movie industry was either unimpressed by the Bald Eagle’s calls or otherwise confused because the mighty soaring call frequently played over a majestic eagle shot is actually just a Red-Tailed Hawk… Happy birding!