Adult bald eagles have dark brown feathers on their body and wings, and white feathers on their head and tail. The adult’s beak and feet are yellow.
Juvenile bald eagles in their first year of life are dark brown over their body wings, head and tail. Their beak and eyes are dark. As they age, juveniles may show white feathers anywhere on the body, especially the breast and under the wings. At three to four years of age they begin to develop the white head and tail of the adult. Their beak and eyes lighten in color as they reach adulthood. A complete white head and tail usually takes until age five or six to develop.
No, bald eagles have feathers covering their heads. The name comes from the old English word “balde” which originally meant white.
In the wild, 70-80% of eagles die before they reach adulthood at five years of age. An eagle that makes it to adulthood might live 20-25 years. In captivity, eagles are known to live much longer, 40+ and up to 50 years, due to a controlled environment, nutrient rich diet and veterinary care.
Eagles use both monocular and binocular vision, meaning they can use their eyes independently or together depending on what they are looking at.
An eagle eye has two focal points (called “fovea” [singular] or “foveae” [plural]) one of which looks forward and the other to the side at about a 45 degree angle. These two foveae allow eagles to see straight ahead and to the side simultaneously. The fovea at 45 degrees is used to view things at long distances. An eagle can see something the size of a rabbit running at three miles away.
The average wingspan ranges from 6 to 7.5 feet (182cm-229cm).
Wingspan of an eagle depends on overall size. Eagles in northern parts of their range tend to be larger overall, including a larger wingspan.
Eagles can achieve 30 mph using powerful wing-beats and even faster when diving after prey (stoop). Bald eagles can dive at up to 100 mph; golden eagles at up to 150 mph.
Eagle feathers, and any part of an eagle, are federally protected. Only individuals and organizations with a permit from the United States government can legally possess any part of an eagle. Enrolled members of Native American tribes can apply for a permit to receive feathers from the US Fish and Wildlife Service’s National Eagle Repository in Colorado.
Bald and golden eagles are protected under the Bald and Golden Eagle Protection Act, passed by Congress in 1940. The Act prohibits the taking or possession of any bald or golden eagle, alive or dead, including any part, nest, or egg, unless allowed by permit . “Take” includes pursue, shoot, shoot at, poison, wound, kill, capture, trap, collect, molest or disturb.
Eagles are also protected by the federal Migratory Bird Treaty Act of 1918, which protects more than 800 species of birds in North America. Feathers and parts of all migratory birds are protected and are illegal to possess without a permit. The federal Lacey Act also prohibits trade in wildlife, fish and plants that have been illegally taken, from being transported or sold and protects eagles and eagle parts from sale.
Bald eagles were removed from the Federal Endangered Species list on June 28, 2007. However, they are still protected under Bald and Golden Eagle Protection Act and other federal laws.
No. Eagles do not have color dimorphism (color difference). Male and females eagles have the same coloration.
Weight varies depending on latitude and gender. Generally, males weigh approximately 25% less than females from the same area. The average weight of a female bald eagle is 10-14 pounds, however there exists great variation depending on where an eagle is from. Southern bald eagles tend to be smaller than those in northern parts of their range. For example in Alaska, females might weigh up to 18 pounds, whereas eagles in Florida can weigh as little as 6-8 pounds. This difference in size between males and females is referred to as reverse sexual dimorphism.
Golden eagles weigh between 6-15 lbs (3-7 kg). Weight varies depending on latitude and gender. Generally, males weigh approximately 25% less than females from the same area. The average weight of a female golden eagle is 10-14 pounds, however there exists great variation depending on where an eagle is from. This difference in size between males and females is referred to as reverse sexual dimorphism.
Golden eagles have dark brown feathers over their entire body, with golden feathers on the nape, or back of the neck. The beak is tri-colored; black at the tip, grayish-blue in the mid-section and yellow at the base. Their legs are feathered to the toes.
Learn more about golden eagles, and see them in the wild on a Golden Eagle Field Trip.
Juvenile golden eagles have distinct white patches near the wrist on the underside of the wing and a wide white band in the tail.
The average clutch is 1-3 eggs with occasional reports of 4. The eggs are laid in 3 to 4 day intervals and hatch in the order they are laid.
Golden eagle eggs are off-white with irregular brownish spotting and average 3 inches long by 2 inches wide. The average weight is 5 oz.
Golden eagles prefer open or semi-open undeveloped habitat. When nesting on cliffs, the selection of the site may be based on an exposure that protects the nest and eaglets from inclement weather conditions.
Golden eagles usually nest on cliffs or in trees in open or semi-open habitat. They avoid heavily forested and developed areas but have been observed nesting on human-made structures such as observation towers or windmills.
Golden eagle nests, while large, are generally smaller and flatter than bald eagle nests. Visit the National Eagle Center to see our life-size replica bald eagle nest – climb in and see just how big it is!
Size varies with geography and gender with females being larger than males and northern birds being larger than southern birds. The average golden eagle’s body length is between 33 and 38 inches (84cm-96.5 cm).
The average wingspan of a golden eagle is 6 to 7.5 feet (182cm-229cm).
Wingspan of an eagle depends on overall size. Eagles in northern parts of their range tend to be larger overall, including a larger wingspan.
Golden eagle – Aquila chrysaetos
Aquila – means eagle in Latin
Chrysaetos – means golden in Greek
Adult golden eagles have brown or hazel eyes, occasionally with some flecks of gold and brown. Juvenile golden eagles have dark brown eyes.
Golden eagle eye. Photo: Guy Marshall
Bald eagle – Haliaeetus leucocephalus
Haliaeetus = member of the sea or fish eagle group
leucocephalus = leuco=white, cephalus = head
There are around 60 different species of eagle in the world. Eagles are found on every continent (except Antarctica).
Birds are warm-blooded, so they rely on warm blood circulating around the body. While the rest of their body is covered in feathers (think how warm down is!), their feet and legs are most often bare.
Bald eagles and other cold weather birds have special circulation in their feet and legs that allow them to withstand very cold temperatures. A complex set of arteries and veins in the leg ensure that most of the heat is ‘exchanged’, before it reaches the exposed legs and feet. This counter-current heat exchange helps to ensure that a minimal amount of heat is lost through blood flowing to the legs and feet.
Bird legs and feet also have little soft tissue, so they don’t require as much warm blood flow. When they need a quick warm up, they can tuck one foot up against their body, underneath all those warm down feathers – a great way to warm up the toes!
Wabasha, MN has long been a wintering area for bald eagles. The Mississippi River remains open year round due to the fast current in the area and Lake Pepin (which freezes) just to the north. Many eagles migrate here for the winter to take advantage of open water and abundant food resources. When bald eagles were rare and endangered, Wabasha, MN was one of the few places where one could reliably view them in the wild.
Wabasha, MN is a unique place where both bald and golden eagles can be observed in the wild. Bald eagles are present year round, with a significant breeding as well as wintering population in the Upper Mississippi River valley.
Golden eagles are present in the winter months in the bluffs and valleys of southeast Minnesota. To learn more about golden eagles, visit the National Eagle Center’s Golden Eagle Project page.
Golden eagles attain full skeletal size in 8-10 weeks although their muscle mass and flight feathers reach full growth post-fledging.
Yes. A golden eagle breeding territory is typically quite large.
Golden eagles are terrestrial predators that feed on mammals, birds and reptiles. They are known to take prey as large as pronghorn or white-tailed deer. Common prey items for golden eagles in the Midwest are squirrels, rabbits, and wild turkeys.
Some eagles migrate. Eagle migration is generally connected to food sources. If an eagle’s breeding territory has ample food sources through the winter, the eagle is less likely to migrate. However, if an eagle’s breeding territory is in northern states where lakes and streams freeze or prey animals hibernate, the eagle will migrate south to find open water and food.
Eaglets in the nest may die from falls, starvation or siblicide. About 50% of eaglets will not reach one year of age. Once fledged, many eagles die from impact injuries, starvation, disease, shooting, poisoning and electrocution. Lead poisoning is a common cause of injury and is most often fatal. The Raptor Center of the University of Minnesota has found that about 25-28% of eagles admitted for rehabilitation in the last forty years have lead in their system.
About 50% of the eaglets die in their first year. Another 20-30% die before they reach adulthood at five years of age.
Bald eagles do not dive into the water but rather skim across the top catching fish near the surface. During salmon runs in Alaska, bald eagles have been observed standing on the shoreline and pouncing on salmon as the fish swims into shallow water. If a bald eagle catches a fish that is too heavy to lift, it may grasp the fish with its talons and use its wings like oars to swim to shore.
No. This is a myth that has circulated for centuries. While no one knows its origins, this myth may be derived from a biblical metaphor. An eagle would die if it plucked all its feathers and could not survive for more than a few days without food.
Eagles monitored with tracking devices have been known to fly 50-125 miles in a day during migration depending on the weather conditions and wind currents.
There is data to suggest that pairs may not migrate together. Rather, each will return to the nest and territory that they have used successfully in previous years. Generally juvenile bald and golden eagles migrate prior to the adults departing.
Eagles have faced difficulties for many reasons in the course of human history. When Europeans settled in North America, eagles were hunted sometimes for food but often as a perceived threat to livestock and competition for wild game.
In the 1950’s a chemical known as DDT (dichlorodiphenyltrichloroethane) was introduced as a widespread insecticide. In 1962, biologist Rachel Carson detailed the impacts of the indiscriminate spraying of DDT and other chemicals on wildlife, and birds in particular in her book Silent Spring. Subsequent research showed that DDT, (the chemical by-product of which was present in many aquatic environments, especially those near agricultural areas) interfered with the calcium processing of birds and resulted in deformed eggshells. Bald eagles, who feed primarily on fish, often received concentrated doses through a process called bio-accumulation. Because bald eagles breed only once per year, and have a low reproductive rate, the bald eagle population declined steeply throughout the 1960’s and 1970’s.
In 1972, DDT was banned in the United States and the bald eagle was put on the newly created Endangered Species List. Habitat conservation and reintroduction efforts helped ensure the successful recovery of the bald eagle and it was removed from the Endangered Species List in 2007.
An eagle has over 7,000 feathers.
Like all raptors, eagles regurgitate indigestible portions of their prey approximately 16-24 hours after eating. Eagles have powerful stomach acids and are able to dissolve bones, so an eagle pellet is typically comprised of just fur or feathers.
A bald eagle can carry about 1/3 its body weight. Eagles are powerful predators that can catch and kill prey many times their own size. However, they are unable to fly carrying more than just a few pounds.
The same pair of eagles have likely used that nest for several years. It is always unfortunate to see a nest destroyed because it represents a great deal of time and effort for those eagles. They are very invested in the space, adding new materials each year as they prepare to raise young.
However, it is not always a total loss for the pair if a nest is damaged. Eagles are not actively using their nests throughout the year. Eagles do not sleep in the nest – they perch on branches at night. The only time eagles are actively in the nest in when they are raising young.
In Minnesota, bald eagles are on the nest February through June. Storms during that period are much more dangerous for an eagle family, and young are sometimes lost when a nest is damaged before they have fledged. But, once the young have fledged, or left the nest, the adults do not use the nest. Both juvenile and adult eagles are spending time hunting and learning to hunt.
The other good news is that the adult pair is very likely to rebuild the nest close by. If the same tree has any viable portion remaining, they may rebuild there. If not, they are likely to choose a place fairly close by. The nest represents a territory to which they are very attached, and have worked hard to defend. They will look for another suitable location within the territory so they can continue to rear young in the area that they know and has been successful in the past.
Golden eagles have a worldwide distribution and are found across the northern hemisphere in Europe, Asia, North Africa and North America.
Golden eagles in North America are primarily found in the Western States and Provinces from Mexico through Alaska. There are also small breeding populations in northern Ontario and Quebec, with a wintering population in the eastern United States. Golden eagles are regular winter inhabitants in the Midwestern United States in the blufflands of southeast Minnesota, western Wisconsin and northeast Iowa, the Driftless region.