Bald eagle (Haliaeetus leucocephalus) on a bird show on the castle Augustusburg, Germany (Photo credit: Wikipedia) |
The American Bald Eagle is the only eagle which is native to North America and it's only on its native continent that one may find it. Alaska, the 49th State admitted to the Union, is home to about 35,000 of the 70,000 total population. British Columbia boasts about 20,000, and the rest predominantly inhabit the Pacific coastline, with a few scattered throughout the rest of the United States. The population is heaviest in the Pacific Northwest due, in part, to a large amount of salmon found there. Eagles depend greatly on fish as the main part of their diets. They will eat small animals such as mice, rabbits, muskrats, duck and snakes and they will resort to eating carrion (dead animals), if necessary. However, they prefer that their food is a fresh source and they are partial to fish.
While Bald Eagles are capable of carrying their food in flight, they can actually only lift about half of their body weight. Although they can dive, catch fish in the water, and swim to shore with them, they have also been known to drown if the fish is too big and they don't let go of it.
The body length, for both males and females, ranges between 29 and 42 inches (73.66 to 106.68 centimeters). The male is usually between 7 and 9 pounds (.497 to .639 stone) and has a wingspan which can exceed 6 feet (1.83 meters). The female is larger and can weigh up to 14 pounds (.99 stone). She can have a wingspan of up to 8 feet (2.44 meters).
In level flight, the Bald Eagle has been recorded at speeds up to 44 miles per hour (70.1 km/h). It can dive (and has been clocked) at speeds of 75 to 100 mph (120.68 to 160.39 km/h). The eagle is capable of riding the thermal air currents in excess of 10000 feet (3048 meters) and can stay aloft doing this for hours at a time.
This species of bird mates for life, and will only seek another mate if their "spouse" dies. They build an "eyrie (also spelled aerie)" in which they incubate their eggs and raise their eaglets until those leave the nest at 12 weeks. An eyrie, or nest, can be built in the tops of giant trees (quite often aspens) or on a ledge of a mountain. The eagles habitually add to their nests until they reach up to 10 feet (2.54 meters) in diameter. The eyries are lined with soft materials such as leaves, feathers, and moss to provide a suitable area for incubating the eggs once the female lays them.
The eggs are usually laid at the end of April, following a fascinating "courtship dance" in early April, which the Eagles perform in midair. They dive and climb, and look to be attacking (locking talons, or claws with) each other during this flight sequence.
After the eggs are laid, the male and the female take turns in hunting, incubating the eggs (34 to 35 days, usually hatching in late May or early June), monitoring the nest, and brooding/feeding the eaglets until they are large enough to fly and leave the nest. This occurs when the eaglets are about 12 weeks old. They develop special flight feathers, which make them look larger than their parents, that serve as extra balance (sort of like training wheels on a bicycle) while they learn to fly.
Hatchlings are light grey when born and turn dark brown before leaving the nest. Young adults have brown and white mottled feathers beneath their wings until they reach 5 years of age. At 5 years, the head and tail feathers turn white. The mature bird is not actually bald. "Bald", at one time, meant "white". Thus the name, "bald eagle". Between the fourth and fifth years, the beak and eyes take on the distinctive yellow color. To see a mature Bald Eagle up close is awe-inspiring. To see one in flight is an experience to cherish for a lifetime.
Preservation Efforts
In spite of the "National Symbols Act" and the "Bald and Gold Eagle Preservation Act," which were both passed in 1940, the Bald Eagle population declined rapidly because farmers killed them for fear of the harm that they could do to their livestock. Hunters and poachers killed them as trophies and for profit, and many were killed accidentally. This seriously alarmed preservationist. Therefore the American Bald Eagle has officially declared an "Endangered Species" in 1947, under a law which preceded the "Endangered Species Act" of 1973. Until 1995, they were listed as endangered in 43 of the 48 contiguous United States. Michigan, Wisconsin, Minnesota, Oregon, and Washington State listed them as "threatened". In 1995, the US Fish and Wildlife Service (USFWS) upgraded their status to threatened in the other 43 states.
In February of 2006, an announcement was made that the USFWS had issued guidelines on how the species should be protected by landowners and others, once the bird is no longer listed as a threatened species. Those guidelines include proposals for laws which prohibit disrupting the bird's breeding, sheltering, or feeding practices or disturbing it in any manner which could cause injury, death, or nest abandonment. Should those proposals be solidified and approved, it could lead to the removal of the Bald Eagle from the "threatened" list.
It should be noted that even if the new guidelines are approved, the American Bald Eagle is still protected under the "Migratory Bird Treaty Act", the "Bald and Gold Eagle Preservation Act", and the "National Symbols Act". It is illegal to possess, take, barter, trade, sell, transport, import, or export eagles. And it is illegal to collect eagles or their body parts, nests, or eggs without a special permit. Possession of a feather, or other body parts, is a felony which can carry a fine up to $10,000 USD and/or imprisonment and this is very strictly enforced. However, federally recognized Native Americans are still permitted to possess those emblems which are traditional to their culture.
One can learn more about these magnificent, beautiful, and majestic birds and how to help with the continuing preservation efforts by visiting the many websites devoted to them.
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