As many of you know, Lyons has its own resident Golden Eagles in LaVern M Johnson Park. Eagles usually nest near their hunting grounds on cliffs. The nest will be near open or partially open habitats because eagles prefer to have a wide view of their surroundings. They may also build nests in human-made structures, and they occasionally build nests in trees in riparian or forested areas.
Nest building typically starts one to three months before egg-laying. A Golden Eagle pair builds a nest primarily of sticks and vegetation—but bones, antlers, and human-made objects such as wire and fence posts have also sometimes shown up in their nests. Next, they line the nest with locally available vegetation. Materials such as grasses, bark, leaves, mosses, and lichens are commonly used. An interesting fact is that they often include aromatic leaves, theorized to keep insect pests at bay.
Resident birds reuse the same nest for multiple seasons and sometimes even alternate between two nests. Nests are immense, averaging five to six feet wide, and two feet high, enclosing a bowl about three feet by two feet deep. The largest Golden Eagle nest found was twenty feet tall and eight and a half feet wide.
A clutch size of one to three eggs is laid and incubated for 41 to 45 days. Eggs are three by two inches on average, and the colors vary from white, cream, or pale pink with small brown spots.
Once hatched, the nestlings are very weak; their eyes are partially open; they are covered with soft down; and they weigh in at about three ounces. The nestling period lasts 45 to 81 days. After the nestling period, the eaglets are ready to fledge. At this time they have flight feathers and take their time practicing flapping their wings before venturing out of the nest.
The U.S. Bald and Golden Eagle Protection Act of 1962 states that harming these birds, their eggs, and their nests is illegal. Although this legislation remains in effect, humans are still Golden Eagles’ greatest threat: it’s estimated that more than 70 percent of recorded Golden Eagle deaths are attributable to human impact, either intentionally or inadvertently. Most recently drones have been found to disturb nests and may even cause parents to abandon eggs and nestlings. So please enjoy our majestic Eagles with binoculars only.
Source: Cornell All About Birds