How Do Bald Eagles Learn to Fly?

Chosen in 1782 as the emblem of the United States of America, the Bald Eagle is known for its strength, longevity and regal appearance. Females weigh between 10 and 14 pounds, with a wingspan 6.5 to 7 feet, while males weigh a bit less at 8 to 10 pounds, possessing a wingspan of 6 to 6.5 feet wide. Bald eagles are found in the coastal areas of North America and inland near large lakes.

Bald Eagle Nests

Bald eagles use large sticks to build hefty nests. Roosting in tall trees or atop cliffs, eagle parents construct homes that reach nearly 9 feet in diameter and weigh up to 2,000 pounds. A female bald eagle will generally lay only two eggs in her sizeable nest, but after about 35 days free space becomes a premium as the eaglets hatch and begin to grow rapidly.

Eaglet Development

Young eaglets grow very quickly, gaining 1 lb. every four to five days. They are able to hold their heads up during feeding at two weeks of age and by three weeks are nearly 12 inches tall. In one month's time they are strong enough to stand and are learning to tear up the food using their claws. At six weeks they begin to rival the size of their parents.

Juvenile eagles have feathers that are a brown and white mix. As they reach sexual maturity at about five years of age, the bird gains the classic bald eagle appearance. With the head and tail feather turning white and the chest and back turning blackish-brown, the unmistakable mark of this American emblem becomes clearly evident.

First Flight

Bald eagle babies attempt to fly between 10 and13 weeks of age. As described in An Eagle to the Sky, Frances Hamerstrom documents her observations of one eaglet's parent beginning a phase of passing over the nest repeatedly without food, unlike ever before. Over time the eaglet began to lose weight, but also became lighter and quicker in its movements. In time it became airborne, if for only a few moments at a time, in its attempts to reach the circling parent.

As the eaglet continued to struggle to reach upward, its strength progressively increased to the point where the parent would begin passing over the nest with food once again. Further encouraging the young little bird's desire, the eaglet eventually hopped out of the nest thus taking its first flight. Coasting on a current of wind it glided across the valley and toppled onto land. Still hungry but unhurt, the effort was rewarded as the parent dropped the enticing food to the eaglet as a hard-earned prize.

Future Flights

Up to 40 percent of baby eaglets fail to survive their first flight. Those who do survive continue to work on their newfound skill by taking short flights, which serve to slowly but surely increase their strength and agility. It is during this time that parents resume the task of providing food for the young birds until they take flight and learn to hunt on their own. The bald eagle can fly at altitudes of 10,000 feet and attain speed of 30 to 35 mph, soaring horizon to horizon.

Feeding Habits

Depending on the prevalence of food, the bald eagle's hunting range can be vast. When food supplies are more limited, it will hunt and scavenge over as many as 1,700 to 10,000 acres. When food supply is plentiful the range will decrease as needed. Living along seacoasts and major rivers and lakes, the bald eagle's diet consists primarily of fish, but also dines on various birds including duck, geese, turkeys and swans. They hunt along both fresh and saltwater regions for fresh food and are more than willing to feed on dead animals for an easy meal.

References

• Bald Eagle Info: American Bald Eagle Information
• Washington Nature Mapping Program: Bald Eagle
• Bald Eagle on Journey North: FAQ by Eagle Expert Peter Nye
• "An Eagle to the Sky"; Frances Hamerstrom; 1988