Daily Activities of Bald Eagles
Bird watching at Wolf Lodge Bay has become increasingly popular over recent years and for good reasons. It’s a place where you can see our national bird in its natural environment, close enough to observe it soaring, hunting or perched on a tree. Eagles circle above the water or peer down from the rugged limb of a larch snag. Studies of their daily activities reveal the complexity and magnificence of bald eagles’ behavior and their role in the delicate balance of nature.
Perching and Soaring
As mid-morning approaches, eagles begin to limit their feeding activity and settle on perches. They seem to prefer certain trees and even favorite limbs. The preferred perches are usually the taller trees with open branches close to the water. If weather conditions are inclement, the eagles are likely to spend the rest of the day perched on branches of their favorite conifers.
On windy days, eagles take advantage of turbulent air currents and soar high above the water. As wind speed increases, so do the soaring activities. During these times, eagles spend less time feeding and perching and more time flying. Eagles have been observed gliding in graceful, almost motionless flight for several hours at a time.
Kokanee salmon were introduced into Coeur d’Alene Lake in 1937, and bald eagles started inhabiting the area soon afterwards. These salmon mature in about three years and reach a length of about 11 inches. Their three-year life cycle ends in November as females lay eggs and males fertilize the eggs. After spawning, the fish die and float to the surface of the water, creating the abundant food source for the eagles.
Although most of the eagles’ fishing takes place during the early morning, some feeding may occur throughout the daylight hours. Dawn finds the eagles arriving at the fishing area from their communal night roost. As they arrive, they position themselves on perches in trees near the water’s edge. From these vantage points, they scan the water in search of dead or dying salmon.
Upon sighting their prey, the eagles glide from the perches, circle above the floating salmon, and in a descending spiral motion snatch the fish from the water. With the salmon firmly grasped in their talons, they return to nearby perches to feed.
Eagles that arrive in the fall before the salmon have begun to spawn or those that remain in the area past January when the salmon supply has diminished must find another source of food. Ducks become their main prey. The impact on the waterfowl population is small though. Waterfowl killed are usually sick or injured ducks.
Pellets of indigestible duck feathers can often be found under the perch trees of eagles. Ground beneath the perch trees where eagles feed is often littered with remains of partially eaten salmon. This seemingly wasted fish is actually an important food source for crows and ravens.