To Watch An Eagle Fly – {Haliaeetus leucocephalus}

Submitted By Warren Young; Alberta, Canada

   The adult American bald eagle is unmistakable in appearance.  It is a striking creature possessing a fierce profile with sharp penetrating yellow eyes. Little wonder it was chosen as America’s national bird symbol back in 1782.  Juvenile specimens resemble the golden eagle. But the conspicuous snow-white head with white tail feathers against the dark overall plumage of the adult bald eagle is unique. The male and female bald eagle display characteristics that only become evident after four or five years from the time it has fledged.

I watched my first eagle after visiting the west coast. Upon entering a semi rain forest several miles from the city of Vancouver in British Columbia on a personal exploring mission, it happened.  After pressing a few branches out of the way to view a pair of mallard ducks that I had heard landing on a woodland pond, I noticed their behavior become increasingly tense. My first thought was that they had spotted my invasion of their privacy and I expected them to fly off the water immediately. Then suddenly an aerial shadow glided over the pond. As I glanced up, a huge bald eagle, tilting its head down toward the pair of ducks drew my attention.  It was silhouetted against the blue sky silently coasting just above the tops of the trees.  I could see its eyes and I believe it saw me. The eagle passed over and the ducks relaxed.  They continued feeding by tipping their tails upward with their heads buried under the shallow water to resume their foraging. But the memory of that first encounter, seeing my first live bald eagle remains clear to me.

For a brief interval during our history in the 60s and 70s – due to harmful pesticides, all of the eagles including the peregrine falcon and many other avian predators across North America became seriously threatened.  Their numbers decreased alarmingly until the use of harmful pesticides was discontinued.  Today eagles of both species including many other raptors have made a remarkable comeback. Eagles are quite common now across the continent of North America and especially on the west coast.  Because eagles are at the top of the food chain, the mammals and carrion they ingest as prey can seriously affect their metabolism. The pesticides caused the shells of eagle’s eggs to become remarkably prone to breakage leaving the un-incubated chicks inside the eggs to perish prior to hatching.  Normally 2 to 3 eggs are laid and it takes 35 days for incubation to occur.  Rarely do three of the incubated eaglets survive. Two are the more common. The stronger chicks will unwittingly kill the weaker third chick out of competition for the food the parents bring to the nest.

During my days as a taxidermist, I mounted several bald eagles and a couple of golden eagles for licensed customers.  Many of my clients displayed the majesty of these birds with open wings over their fireplaces. Some clients dramatized the mount with the American flag as a background displaying the familiar graphic displays we often see in commemorative magazines or on book covers.  Those who could not obtain official legal permits upon finding dead eagles alternately commissioned some of our top wood carvers to make replicas of these beautiful birds.  Mature eagles have a wingspan of 70 to 90 inches from tip to tip of their primary feathers.  That is an impressive species of avian wildlife second only to the condor.

Eagle nests are called an “aerie”.  They are usually situated overlooking a river or the coast from a tall Douglas fir, Cedar, or similar species of tree in the west. They are constructed of stout branches in the crotch of a tree. Or they can be located on a precipitous cliff overlooking a valley or the ocean. Some of these amazing nests are anywhere from 5 to 9 feet in diameter.  They continue building upon the same original nests for a number of years.  One observer reported finding an aerie that was twelve feet deep, suggesting the nest had been built there on top of the preceding nest for a considerable time.  Eagles have been known to live up to thirty years in the wild and they mate for life.  If one dies, only then will the survivor take another mate. Eagles are very territorial and will fiercely defend at least one or two square miles of nesting territory from other eagles and potential intruders. They have been observed flying at heights of 10,000 feet and can travel at speeds up to 35 miles an hour.

Most birds possess colored vision and eagles are no exception except that their eyesight is extremely remarkable.  They have two foveae or centers of focus that enables them to see clearly both forward and off to the side at the same time. The nictitating membrane cleans their eyes from any dust or particles from front to back every three or four seconds.  The eagle sees with a maximum sharpness of at least four times better than a human with 20/20 vision. An eagle doesn’t miss very much and can spot their prey at tremendous distances. They have a special extra transparent eyelid that acts as powerful sunglasses enabling them to fly toward the sun without being blinded.  Other species of birds do not possess that advantage.  When being annoyed by crows or ravens an eagle can simply fly higher into the sky against the sun and remain at peace.

Because eagles don’t hunt during the night like most owls do, their hearing is still only slightly less than an owl’s.  From the time they leave the nest, they become engaged in a sort of eagle boot camp. It really takes a good four years for a young eagle to mature into a fully effective predator.  This is evident by the white head and tail feathers that adorn their vesture after those four years have passed. It signifies a sort of military service record. At that point in their lives they are finally ready to find a mate and move into a territory of their own.

For an eagle learning to fly and to fully master the technique, it becomes one of their most dangerous and vulnerable exercises. It is estimated that 40% of young eagles don’t survive their first flight.  The young eagle is on its own practicing flying and it takes them about five weeks to really get the hang of it.  But once they master the art of flying, their air born exercises are amazing.  They learn to hunt mainly by watching their parents from nearby promontories or coasting along with them learning to use the air currents to the best advantage.  The molting process is always a constant and gradual thing with eagles and never seems to curtail their flying exercises. Avian ornithologist philosophers refer to the eagle as an icon that consistently renews it’s feathered overcoat – always in the right places.

I prefer to comment on the eagle in a positive personal sense. They really don’t have too many negative characteristics to demote them in any way from the noble status they’ve been officially elevated to.  Eagles represent a remarkable emblem as the American national bird. While they often feed heavily in season on carrion along the salmon spawning rivers of the northwest, they do occasionally take live prey.  As a human, I like to credit that characteristic with the idea of keeping things neat and tidy. By taking advantage of this innate ability to make perfect use of a species of fish, the pacific salmon that ultimately dies after spawning, eagles seem commendable. Bald eagles are therefore considered beneficial by man and are naturally resourceful.

I listened to a story once involving the intelligence of the eagle. It explained a sort of ritual they performed when the female selects a mate.  Once they meet for the first time and do a few aerial pirouettes, the female watches the male do a special performance for her.  But first she selects an average size stick and rises high into the sky with the male following.  Then she drops the stick.  The male immediately dives, plunging headlong after the falling stick.  He catches the stick just before it hits the ground.  Next, the female chooses a larger stick. This time she doesn’t fly quite as high before dropping it. The male repeats the behavior and catches the stick again before it hits the ground.  Humorously speaking, this would appear to be an excellent test the female initiates before selecting a satisfactory mate.

I personally like to classify the bald eagle as a dominant monarch of the sky in that they will chase other species of raptors away making them drop their prey. Eagles will then confiscate the prey.  Which in a way signifies to the other species that they have invaded an eagle’s hunting territory. Their territory extends for a radius of about two square miles. I suppose it’s another way we look at things. But let’s not be too hard on the national bird. Defending one’s territory is not an indefensible argument.  We do it ourselves to defend our right to freedom and peace. This has been costly for us, yet ultimately rewarding when we are successful.

Oddly enough, sometimes eagles will perform some unusual aerobatics, like locking their talons together at high elevations and tumbling softly earthward. There’s a story that appeared in a Georgia newspaper once where two eagles were seen locked talon to talon where they bounced onto a golf course and remained locked together for several hours. A golfer stretched forth his club and gently touched them. They immediately unlocked their talons and flew away.  This had nothing to do with copulation. It’s just an odd ritual that they have been observed performing.  Eagle copulation is done on tree limbs or on the ground.  That too has been observed and verified.

As a taxidermist I can vouch for the fact that distinguishing between a male and female bald eagle can be determined by examining the size of the beaks. Female bodies in most avian predators are always larger than the male. The beak of the female is always deeper from top to bottom than a male’s.  Just as the head and tail feathers turn white, the beaks and eyes turn yellow when the eagle reaches about five years of age.

In summary, my personal take on the bald eagle as the U.S. national bird, was an excellent choice and was wisely classified as a highly intelligent, powerful and free spirited bird that deserves its official title. If you like, eagles possess unwavering patriotic attributes concerning the defense of its territory. Let’s just call a spade a spade. The eagle also sets an example of unwavering loyalty concerning its mate until death. What a wonderful societal lesson we might all learn from simply watching the eagle.

Bald eagles were finally taken off the endangered species list on June 28, 2007.  It is still protected throughout the United States and Canada and is expected to remain a valued and beneficial species of bird indefinitely.


About Bob Hatcher

Primary Blog Contributor, American Eagle Foundation
This entry was posted in Conservation & Management, Life History, Biology, & Behavior, Symbolism. Bookmark the permalink.

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