Out of all the raptors or birds of prey, the Bald Eagle not only sits at the top of the food chain, but its sheer power and majestic appearance make it one of the most interesting species of birds. So interesting in fact that this bird was selected to represent our Country, the United States Of America.
The Bald Eagle was chosen as the symbol of the United States of America on June 20, 1782. Because of its great strength, stately looks, and long life, the Bald Eagle was selected as the national bird following the American Revolution. Another reason the Bald Eagle was chosen is because it is native to North America.
In the following article, we will explore the different aspects of this special and magnificent animal – everything from eye color to its bout with extinction. The sight of the Bald Eagle in the wild is the epitome of nature and freedom at its best.
Great Seal of the United States
The Great Seal of the United States was first adopted and used in 1782. It is used to authenticate documents issued by the federal government of the United States. The State Department is charged with the safe keeping of the Great Seal of the United States by an act of Congress on September 15, 1789.
On July 4, 1776, the Declaration of Independence was signed. Before the Continental Congress adjourned, the task of designing the Seal was given to Benjamin Franklin, Thomas Jefferson, and John Adams. After submitting the design, the Continental Congress rejected their attempt.
The project to design the seal then went to James Lovell of Massachusetts and John Scott and William Houston, both of Virginia. Even though this second attempt was also rejected by the Congress, certain parts of each design of the first two attempts were ultimately approved.
For example, the olive branch which is the symbol of peace, the shield with red and white stripes on a blue field, and thirteen stars were approved as part of the design.
A third committee was formed and this is the first time an Eagle was approved as part of the Great Seal of the United States. Charles Thompson, who was the Secretary of the Continental Congress, created the fourth design. However, William Gaston made some slight changes.
On June 20, 1782, the Continental Congress ultimately approved the design - almost six years after Benjamin Franklin, Thomas Jefferson, and John Adams were given the task to design the Great Seal of the United States. Interesting - Finally approved after four submissions – sounds like our Congress today!
In the center of the seal is a Bald Eagle with its wings outstretched supporting the shield. The Eagle’s left talon is a bundle of 13 arrows representing the arrows of war and the thirteen original colonies.
In its right talon is an olive branch representing a strong desire for peace, but will always be ready for war. The eagle clutches a scroll in its beak with the motto “E pluribus Unum” meaning “Out of many, One”.
Over the Eagle’s head is a six pointed star with 13 stars on a blue field. The shield is in the center supported by the Eagle. It is red and white representing the flag on the United States. On the reverse side of the Great Seal (which is never used) is an unfinished pyramid. There are 13 layers referring to the 13 original states. On the base of the pyramid is inscribed MDCCLXXVI referring to the year 1776 – the year of the United States Declaration of Independence.
At the top of the pyramid is an eye enclosed by a triangle. This represents the eye of God watching over humanity. Even though the back of the Great Seal is never used, both the front and the back of the Seal are pictured on the back of the one dollar bill pictured above.
The Bald Eagle, The Wild Turkey, and Benjamin Franklin
The story of Benjamin Franklin proposing the Turkey instead of the Bald Eagle as the centerpiece of the Great Seal of the United States is false. This myth has persisted through time and is still believed by many today.
In a letter written to his daughter while he was in France, Franklin cast doubts on the Bald Eagle as the Country’s national bird. The following is an excerpt from his letter:
“For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral character. He does not get his living honestly. You may have seen him perched on some dead tree near the river, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him.”
“With all this injustice, he is never in good Case but like those among Men who live by Sharping & Robbing he is generally poor and often very lousy. Besides he is a rank Coward: The little King Bird not bigger than a Sparrow attacks him boldly and drives him out of the District. He is therefore by no means a proper Emblem for the brave and honest Cincinnati of America who have driven all the King birds from our Country.”
“I am on this account not displeased that the Figure is not known as a Bald Eagle, but looks more like a Turkey. For the Truth the Turkey is in comparison a much more respectable Bird, and withal a true original Native of America… He is besides, though, a little vain & silly, a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on.”
A Bald Eagle Nest As Big As A VW Bus!
The largest Bald Eagle nest of record is located near St. Petersburg, Florida. It is also listed in the Guinness Book of World Records. The nest was measured in 1963 and was found to be 9 ½ feet wide and 20 feet deep. It is estimated to weigh 4,409 pounds which is 1400 lbs heaver than a VW bus.
Bald Eagle nests are usually built in trees. They prefer the nest to be located as high as possible and near a body of water, such as lakes, rivers, or coastal areas. It is not uncommon for a nesting pair to have more than one nest within their territory. After years of use and adding to the nest, the nest can become quite large. However, the typical or average nest is about five feet in diameter.
The shape of the nest is dependent upon the tree and its branches. A cylindrical shaped nest would be a result of sticks being placed in the forks. Disc shaped nests are built on ledges, on the ground, or on a level tree branch.
The fact that Eagles have the largest nests of any bird is easily understood when you consider the size of the fledglings and two adult Bald Eagles that occupy the nest.
Range, Habitat, and Diet
The normal range of the Bald Eagle includes northern Mexico, all of the continental United States, and most of Canada. It is the only Eagle native to North America.
The habitat of the Bald Eagle is located in close proximity of rivers, lakes, seacoasts, and marshes - wherever fish are plentiful. They prefer large bodies of water, preferably with a circumference greater than seven miles and large lakes greater than four square miles. These bodies of water are optimal for Bald Eagle breeding pairs.
Of paramount importance for the Bald Eagle is an abundance of large trees near bodies of water. The trees must provide an excellent vantage point for hunting and be well over 20 feet tall – the higher the better. As far as nesting trees are concerned, the nest could be as high as 125 feet.
In Florida, nesting habitats consist of mangrove swamps, lakes, rivers, and seacoasts. Preferred nesting trees in Florida are pine trees and cypress trees. However, along the coastal areas of Florida, mangrove trees are used as nesting sites.
Interestingly, the greatest distance of a Bald Eagle’s nest from water is on record to be 1.9 miles in Florida.
The Bald Eagle is opportunistic in its feeding habits. Fish is a staple for Bald Eagles. In fact, up to 50% of their diet is fish. However, depending on their territory, like the northwest, up to 90% of their diet is fish. They eat waterfowl and many different species of small mammals.
Eagles will steal and eat the food from the other birds’ nests. Their diet also consists of small birds, reptiles, crabs, invertebrates, and amphibians. Their prey can be a live and fresh kill or a dead, decaying carcass (carrion).
Life Cycle of the Bald Eagle
Bald Eagles living in different geographical locations will lay their eggs at different times of the year. For example, in Florida, the Bald Eagle may begin laying its eggs in November. On the other hand, Bald Eagles in Alaska will begin laying their eggs in the latter part of April through May. Once all of the eggs are laid, the incubation period begins. The incubation period lasts for approximately 35 days.
The Bald Eagle’s eggs weigh 4 to 4.5 ounces on average and are about 3 inches long and 2 inches wide. The eggs are off-white in color and are oval in shape.
Once the incubation period begins, both the male and the female alternate sitting on the eggs. The female spends more time on the eggs than the males. Usually while one of the nesting pair sits on the nest, the other is on a mission for food. Sometimes, however, one will perch nearby to protect the nest.
While sitting on the nest, the eggs are rolled over by either of the two parents. They do this to prevent the yolk and blood vessels from sticking to the surface of the inner egg shell.
After the baby chicks hatch, they will be fully grown in nine weeks. Once most of their wing and tail feathers have developed, the fledgling can leave the nest. Sometimes the adults will encourage the fledglings to fly by forcing them out of the nest.
By the time they reach the age of approximately 20 weeks, the bond between the parents and their young fades and the young birds begin their journey.
The young Eagles will spend the next four to five years developing into an adult Bald Eagle learning the skills necessary to survive. Once adulthood has been achieved, they will begin looking for a mate and will establish a territory. The territory is usually located within 250 miles of where the Eagles were hatched, and the life cycle begins again.
Physical Features Of The Bald Eagle
Before they reach maturity, young birds have brown plumage with speckles of white under their wings. Their head, beaks, and eyes are all brown. The plumage of an adult Bald Eagle is dark brown. His head is white and his tail is also white and wedge-shaped. Bald Eagle bills and legs are bright yellow in adult birds.
The eyes of an adult Bald Eagle are yellow. Their eyes are fixed in their skull and they cannot move their eyeballs within their socket. Eagles are also equipped with eyelids that are similar to ours. The difference being they have a third eyelid called a nictitating membrane. The membrane provides moisture and protection as well as cleaning the eyes.
The Eagle’s eyes are among the strongest of any animal. It is, in fact, estimated to be four to eight times stronger than human eyes. Color vision and clarity are one of the very important features of the Eagle’s eye.
The skeleton of the Bald Eagle weighs only about eight ounces and its feathers weigh about a pound. The beak has a significant curve in it which is used for tearing flesh. The top or upper mandible overlaps the lower mandible. The talons and beak are made of keratin, like our fingernails and hair.
The Bald Eagle has a body length of 28 to 40 inches. The wing span is six feet to seven feet seven inches. The average female weighs about 12 pounds and is about 25% larger than the male. The weight for males is about 9 pounds. The size and weight will vary depending on their geographic location.
Eagle Toes and Talons
The Bald Eagle has strong, muscular legs. When these leg muscles are contracted, they clamp down on the tendons in the lower legs and toes. This constriction closes all the talons together in an extremely tight grip.
The foot consists of four muscular toes, powerful enough to carry a fairly large fish as the Eagle flies through the air. If the fish is too heavy for the Eagle to fly, it will use its wings and paddle to the shore where it can begin to feed. This is especially important because fish are the major source of an Eagle’s diet.
Bald Eagles do not have feathers on their legs or on their feet. Instead, they have scales. Each foot has four toes and each toe is equipped with a very sharp and piercing talon. Three of the toes face forward and the fourth toe or the hallux faces backward to assist in grasping prey.
When the toes of the Eagle’s foot are clenched, the three front toes face toward the back of the foot and the fourth toe or the hallux faces the front. The hallux talon is always longer than the other regular talons. In females, this talon is longer than in males. Therefore, by measuring the hallux talon of an Eagle, we can determine the gender. The hallux talons of female Eagles are almost 2 inches long compared to an inch and a quarter on males.
In the early 18th century, the Bald Eagle population was estimated to be in excess of 300,000 birds. However, during the 1950’s, the population had declined to only 412 nesting pairs. Several factors contributed to this dramatic decline.
Loss of habitat was one of the important causes of the Bald Eagle’s decline in population. The increase in human population, logging, and development of waterfront property for housing have all negatively impacted the Bald Eagle population.
Also, legal and illegal shooting had a major impact. The Bald Eagle was thought to be responsible for taking lambs and small children with their talons. At one time even a bounty was placed on the Bald Eagle. As it turns out, the Bald Eagle was innocent on both accounts, but sadly it wasn’t until about 70,000 Eagles were shot and killed.
Chemical Effects Finally Realized
The Bald Eagle was severely affected in the mid-20th century by a pesticide known as DDT. This new pesticide was to control mosquitoes and other insects. However, DDT had a devastating effect on Bald Eagles, as well as other animals. The problem occurred when DDT and its residue washed into nearby waterways, such as lakes, streams, and rivers causing fish and aquatic plants to absorb it.
Bald Eagles were poisoned with DDT when they ate the contaminated fish. The pesticide also caused Bald Eagle eggs to have very thin shells, causing a failure in eggs to hatch. Furthermore, many eggs were broken during incubation because of the thin shells.
In addition to the consequences of DDT, some Bald Eagles died from lead poisoning after feeding on Ducks and other Waterfowl which had been shot by hunters. By 1963, approximately 487 pairs of nesting Bald Eagles remained. A combination of loss of habitat, shooting, and DDT poisoning brought the Bald Eagle to the brink of extinction.
Recovery Of The Bald Eagle Population
There is a series of events which have greatly aided in the recovery of the Bald Eagle populations. The 1918 Migratory Bird Treaty was the Bald Eagle’s first act of protection. The treaty was enacted by the United States and Canada. In 1940 the Congress of the U. S. approved the Bald and Golden Eagle Protection Act which prohibited commercial trapping and killing the Eagles.
In 1962 a book entitled Silent Spring was written by Rachel Carson which pointed out the dangers of DDT to wildlife, birds, bees, agricultural animals, domestic pets, and even humans. In 1967 the Bald Eagle was declared an endangered species. Amendments to the Protection Act of 1940 further restricted commercial use and increased penalties for those who violate the law.
As a result of DDT being banned, the Bald Eagle population has increased greatly. In the early 1980’s the estimated total population was approximately 100,000 birds. The Bald Eagle was officially moved from the Endangered list and placed on the Threatened list in 1995.
In 1999 a proposal was made to remove the Bald Eagle in the lower 48 states from the list of Endangered and Threatened Wildlife. The Bald Eagle was removed from the Endangered and Threatened Wildlife List in 2007.
Totem poles contain carvings and are made from large trees, usually giant cedars or western red oaks. Because of their hardiness and their resistance to rot, these trees were a logical choice. Totems are found primarily in British Columbia, Washington, and southeastern Alaska. Their function is to preserve the cultural heritage of Native people in the North American Pacific Northwest.
Through the images carved into the totem pole, Native American tribe totems tell a story that mirrors the history of a tribe, reminding them of their lineage or their mystical past and creation myths. Of particular interest are those animals considered to be power animals that appear on totem poles.
Two examples of these power animals are the Eagle and the Raven. The Eagle symbolizes great strength, courage, leadership, and prestige. Dreaming of an eagle symbolizes nobility, pride, fierceness, freedom, superiority, courage, and powerful intellectual abilities.
In sharp contrast to the Eagle is the Raven. The Raven represents creation and knowledge – bringer of the light. However, dreaming of a Raven symbolizes betrayal, disharmony, and misfortune.
Fast Facts About The Bald Eagle
• How much weight can a Bald Eagle carry? They can carry approximately four pounds.
• How fast can the Bald Eagle fly? The Bald Eagle can flap its wings and soar at about 30 mph. They can dive at speeds up to 100 mph.
• Do Bald Eagles mate for life? Yes, however, if one dies, they will find another.
• How many eggs are in a clutch? The average is two eggs.
• What do Bald Eagles sound like? They usually make a series of high-pitched whistling notes.
• How high do Bald Eagles soar? They can soar at altitudes in excess of 10,000 feet.
• How large is the Bald Eagle’s territory? The size of the territory varies depending on the habitat and food supply. It is approximately 0.6 to 1.2 square miles.
• How long do Bald Eagles live? The average life span in the wild is between 20 to 30 years. In captivity, they have been known to live 50 years.
Here is the birding gear I use in the field.
Do Bald Eagles eat the bones of their prey?
Yes, Bald Eagles do eat the bones of their prey. Their digestive systems are able to dissolve the bones which provide important nutrients.
What is the mortality rate of Bald Eagles during their first year?
Even though the Bald Eagle has no natural predators, the mortality is very high – greater than 50%.
Why are Bald Eagles called “Bald” Eagles when they have white feathers on their head?
They are called “Bald” because originally the name comes from an old English word “piebald” which means “white-headed”. Also, from a distance, the Bald Eagle may appear bald with its white head against its dark brown body.