Every year in the early spring, I am mesmerized by the the live eagle cams on the Internet. I have some favorite pairs of eagles that I watch lay their eggs, hatch, and raise their brood of 1 to 3 eggs. Eagles build their nests, working together, several months prior to mating. Bald Eagles typically build high in mature trees with strong branches that can hold at least 1,000 pounds. Each year, they return to the same nest and make it bigger than the prior year. Then sometime in late-February through March, they mate and the female lays her eggs 5 to 10 days after mating.
The eagle’s nest or “aerie” is fascinating. The sides are made of intertwining sticks and branches, and are filled with corn husks, and other soft materials that are found in the eagles’ habitat, including down from their feathers. The part of the nest that will contain the eggs is called a “bole” and will have softer materials such as moss and will include the feathery down from the adult eagles. An average nest is 4 to 5 feet in diameter and 2 to 4 feet deep. However, the largest nest ever recorded was located in St. Petersburg, Florida and was 9.5 feet in diameter and 20 feet deep. This nest weighed 3 tons!
Eagles are territorial and will come back to the same nest year after year. They will continue to add to the nest which can grow to an astounding depth and weight. They sometimes will have alternate nests in the same nesting territory and will alternate usage from year to year. Some eagles have been known to use the same nest for 35 years. Eagles build close to lakes and rivers because those provide a good food source.
Eagles reach sexual maturity around 4 to 5 years. They mate for life, unless something happens to one of them, and then they will seek out another mate. When the mating ritual begins, they become aerial acrobats swooping in flight and cartwheeling. This behavior is thought to test the “strength” and “agility” of the eagle’s potential mate. This behavior, however, is not the actual mating. This is consummated on a tree branch or in the nest of the mating pair. After the female lays the first egg, incubation begins and continues for approximately 35 days.
The eaglets are cared for by both parents, and the young will remain in the nest for 11 to 12 weeks. Eaglets are mostly fed fish, but the parents will supplement with other food sources such as ducks, geese, or other birds. Once the eaglets fledge and their downy feathers are replaced by juvenile feathers, the parents will expect them to fly. Fledglings will practice flying in the nest, and will stay on tree limbs and return to the nest after they begin flying. The parents will actually withhold food in order to encourage the young to leave the nest.
Fortunately, these birds are no longer endangered, but they are protected by multiple Federal laws. Possession and transportation of an eagle or eagle parts, including feathers, eggs or parts of an eagle’s nest are prohibited by law. Under the Bald and Golden Eagle Protection Act, the first offense is considered a misdemeanor and punishable with one year in prison and a $100,000 fine, but a second offense is a felony and punishable with two years in prison and a $250,000 fine. The bald eagle has been the national bird of the United States since 1782, and is the “most pictured bird in all of America” appearing on many government documents. It symbolizes “strength, courage, and freedom.” Therefore, let’s not only admire and protect this majestic bird, but let’s keep it free to fly high with outspread wings.
Sources
https://www.nationaleaglecenter.org/eagle-nesting-young/:
https://journeynorth.org/tm/eagle/annual/facts_nest.html
https://www.fws.gov/uploadedfiles/region_5/nwrs/central_zone/montezuma/eaglefacts.pdf
https://www.va.gov/opa/publications/celebrate/eagle.pdf
