Everything You Wanted to Know About the Bald Eagle
The American bald eagle is perhaps the most majestic and revered of all birds of prey across North America. Chosen by our forefathers as a symbol of strength and pride for the United States, and honored and respected by Native Americans for centuries, this beautiful bird is perhaps the most famous of all birds of prey.
Unlike many other birds of prey that are found throughout the world, the bald eagle is found only in North America. There is perhaps nothing more gratifying for the bird enthusiast than catching a glimpse of the bald eagle in the wild.
At one time the bald eagle was abundant across North America with some estimates approaching 500,000 birds in the 18th and 19th centuries. Sadly, however, human intervention in the form of habitat loss, outright killing, and the use of pesticides and chemicals caused a catastrophic decline in their population, and by the mid-1960s there were but 450 nesting pairs remaining in the lower 48 states.
The widespread use of the pesticide DDT contributed greatly to the decline as this pesticide worked its way up through the food chain into the systems of the eagles. This resulted in very brittle and thin-shelled eggs that were unable to withstand the weight of the mother. The eventual banning of DDT in 1972 in the United States and in 1989 in Canada was the start of the recovery period for the bald eagle.
Today, the bald eagle is perhaps the greatest comeback story ever to take place in the history of endangered species. In 1995 the bald eagle was officially removed from the US endangered species list and placed on the threatened species list, and in 2005 it was removed from the threatened list.
Although it is difficult to get an accurate count of the bald eagle population, it is estimated that there are as many as 100,000 across North America with half of these located in Alaska. Another 20,000 or so live in Canada’s British Columbia, making the northwestern coast of North America the highest concentrated area of bald eagles anywhere. This area is prime eagle territory due to the large number of salmon that populate the waters of the Pacific Northwest.
With their population continuing to recover, today it is possible to see the bald eagle in the wild in many locations once thought of as impossible. Here in Massachusetts, there were 38 nesting pairs of eagles in 2012, and at last count, there were over one hundred eagles spending the winter here. Certainly a remarkable recovery. It is now not uncommon to see a bald eagle perched on a tree along the Connecticut River contemplating its next meal.
The bald eagle is a large bird measuring approximately thirty-six inches in length. As with other birds of prey the female is larger than the male by about twenty-five percent. Adult females will weigh an average of thirteen pounds while the adult male averages about nine pounds. Their wingspan measures between 6 to 7 ½ feet from wingtip to wingtip so this is a very large bird. The only North American birds larger than the bald eagle are the California condor and the golden eagle, which is just slightly larger. While most people consider the bald eagle to be black and white in color, the plumage of an adult eagle is actually a dark brown to go along with its distinctive white head and tail. The feet and beak of the bald eagle are a bright yellow.
The bald eagle will usually nest near the coast or a large lake or river as their diet consists mostly of fish. They are not opposed to hunting small mammals and will steal food if the opportunity presents itself. The bald eagle, like other birds of prey, will generally mate for life and they will construct a nest high off of the ground. The nest of the eagle is one of the largest of any bird in the world and can measure up to eight feet across and thirteen feet deep. These huge nests are made of sticks and can weigh up to a ton.
The eagle will mature at about four to five years of age, and a nesting pair will produce a clutch of one to three eggs usually in late winter to early spring. The eggs will incubate for four to six weeks with both parents sharing in the incubating duties. Once hatched the eaglets will grow quickly adding about a pound every four to five days. It will take approximately ten to twelve weeks for their first flight and by this time they are almost as big as their parents.
After fledgling, the young eagles will remain near the nest for six to eight weeks while they hone their flying and hunting skills. It will take a full five years for the eagle to mature, and during this period their appearance will gradually change from more of a golden eagle look to the classic bald eagle look with the white head and tail feathers.
- The bald eagle is also referred to as the fishing eagle and the American eagle.
- A nesting pair of eagles in Florida built a nest that is over 12 feet wide, 18 feet deep and weighs an estimated three tons. It is credited as holding the record for the largest nest ever constructed.
- There are actually two subspecies of the bald eagle, the Southern bald eagle, and the Northern bald eagle. The Northern bald eagle is a little bigger than it’s Southern brethren. Southern bald eagles are found south of 40 degrees latitude generally along the Gulf Coast to Florida. The Northern bald eagle is found north of 40 degrees latitude and is common across most of North America.
- The average lifespan of the bald eagle in the wild is from fifteen to twenty years although they can live up to thirty years.
- The bald eagle has excellent vision that is four times that of a human with perfect vision.
- The bald eagle is the National Bird of the United States.
- The bald eagle can glide in flight at up to 45 mph and can dive at up to 100 mph.
- The bald eagle can fly as high as 10,000 feet in altitude.
Questions & Answers
After an eagle is old enough to take care of itself, will it stay in the vicinity of its parents?
Once they can hunt on their own, usually seven to eight weeks after fledging, a young eagle will leave the nesting area and set off on its own. Where they go usually depends on the availability of food. During the first four to five years of their life young eagles can travel quite a bit in search of food, and generally will not stay in the territory of their parents.Helpful 4
What is the bald eagle's life-span?
The average lifespan of a bald eagle in the wild is about 25 years, with the longest recorded banded eagle having lived to 38 years. In captivity, they will generally live longer, up to 50 years.Helpful 3
What do bald eagles eat?
Their diet is primarily fish, but can also include small mammals as well as other birds and waterfowl.
Bald eagles are attacking the chickens and small domestic pets in my area. How can we discourage them? We are at their mercy.
I’m not sure there is a lot you can do. Provide as much cover as possible for the chickens and hope they recognize when the eagles are in the area. I read recently where someone trained a large-breed dog to protect their chickens. Depending on how large an area you have maybe some sort of netting overhead to provide cover is in order?
This does appear to be a big problem, especially with chickens, and one that is very difficult to solve. Bald eagles are bold predators and are not easily discouraged. The problem is you can’t sit and watch for them all day. Perhaps some sort of siren or whistle system can be used, but again, this means someone has to be watching for them. I would provide as much cover as possible and get a large dog to live with the chickens and become their protector.
Why do bald eagles have such great vision?
Most birds of prey including the Eagle have better eyesight than humans. They can see about 4 to 5 times farther than humans. The Eagles retinas are more densely coated with light-detecting cells called cones than human retinas, enhancing their ability to resolve fine details. Also, whereas the fovea in the human eye resembles a shallow bowl, the fovea of the Eagle is U-shaped. The greater depth of the fovea allows their eyes to function much like a telephoto lens, enhancing magnification in the center of their visual field.
© 2012 Bill De Giulio