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Cross Timbers Wildlife News - Jim Dillard
December 2002



Jim Dillard is a Wildlife Biologist for Texas Parks & Wildlife. He writes from Mineral Wells TX.

On The Wings of Eagles

The first committee to recommend a seal for the newly declared United States was appointed the same day the Declaration of Independence was signed in 1776. It was composed of Thomas Jefferson, Benjamin Franklin and John Adams. They couldn't agree as there were a few other more important issues to deal with at the time. It wasn't until June 20, 1782 that a third committee recommended and Congress adopted the American or bald eagle as the official motif for the seal. Years later, Ben Franklin referred to them as "lousy" birds, known for their thievery, cowardice, and habit of eating carrion. He thought the wild turkey was more respectable. Although the Congress had named the bald eagle our national bird, it took another 158 years to pass a law providing them protection.

One of my first encounters with bald eagles was up on the High Plains of the Texas Panhandle north of Dumas. It was winter and ice and show blanketed everything in sight, except for an open pool of water out in the middle of a big playa lake. If there was one duck out there, there was 20,000. As I glassed the playa with my binoculars, all the ducks suddenly became airborne with a thundering roar. I knew I hadn't spooked them because I was a long way off. It wasn't until I spotted a pair of bald eagles lazily circling high overhead that I realized the terror ducks must have for bald eagles. On another occasion, I watched a bald eagle flying low over a playa carrying a duck with its feet it had either just caught or found dead - they aren't particular.

Bald eagles are found throughout North America from Florida to the Aleutian Islands of Alaska. In the Cross Timbers Country of North Texas, bald eagles are winter residents, arriving about the same time as migrating waterfowl in the fall and remaining until early spring. I've seen them often along the Brazos River and around the larger reservoirs here in North Texas where they feed on fish, waterfowl, waterbirds, small mammals, turtles, carrion, and whatever else they can scavenge. A landowner south of Mineral Wells once told me he saw one feeding on something out in his field and on investigation, found it was dining on a dead buzzard.

Wintering eagles down in central Texas on Lake Buchanan and the Colorado River have become a tourist attraction. Another good bald eagle watching location is just below the dam at Lake Texoma in Grayson County. These eagles return to the northern United States, Canada and Alaska to nest during the spring and early summer. Another group of resident bald eagles nest during late winter along the Gulf Coast from Florida to Texas and on reservoirs in East Texas. On a couple of occasions, I've observed bald eagles attempting to nest here in North Texas at Lake Worth and Lake Ray Roberts.

The bald eagle's scientific name, Haliaeetus leucocephalus, is Greek, meaning "sea eagle" with a "white head". It's not until they reach adulthood at 4-5 years of age that the white head and tail feathers appear. As young birds, body feathers are mostly dark with irregular white patches on the wings and at the base of the tail, similar to that of immature golden eagles, so identification can be a little tricky. Once mature, there's no other bird more majestic or regal in appearance than a bald eagle with their 6-7 foot wingspan, bright yellow beak and legs, powerful talons and those penetrating "eagle eyes". Their sight is four times sharper than someone with 20-20 vision. In soaring flight, wings are held flat. Their high-pitched kweek-kik-ik-ik-ik call is described as a squealing cackle and is made by both sexes. Size-wise, they measure about 3 feet from head to tail and weigh 7 to 10 pounds. Females are bigger, up to 14 pounds, and with 8 foot wingspans. They're believed to live up to 30 years in the wild.

Bald eagles mate for life and construct massive stick nests, called aeries, that are reused for many years with a little annual touching up. Some nests are known to be 35 years old and weigh over a ton. Nests may be 6-10 feet across and 10-20 feet deep, usually constructed in the top of a tall tree or occasionally on a bluff. During courtship flight, bald eagles often grab each others talons and tumble downward or drop sticks for the other to catch in mid-air. Although 2-3 bluish-white eggs are laid, only the eaglets that hatch first will survive since they'll be a little larger and more aggressive when food arrives at the nest. Both parents incubate the eggs for 34-36 days and feed the young for another 3 months before they leave the nest. They'll continue to be fed by the parents for another 4-6 weeks until they learn to hunt on their own.

Bald eagle populations have declined dramatically over the past 200 years, primarily due to habitat loss, shooting, use of agricultural pesticides such as DDT and Dieldren and lead poisoning from ingested lead shot found in the tissue of dead or wounded waterfowl. In 1940, the Bald Eagle Protection Act was passed making it illegal to kill or harass eagles. In 1969, further protection was provided under federal endangered species laws and Texas followed suit in 1973. In 1972, the EPA banned use of DDT in the United States and now only steel shot may be used when hunting waterfowl. These and other recovery efforts appear to be helping turn the tide of the bald eagle decline. At present, it is estimated there are 70,000 bald eagles and about half of those live in Alaska.

Today in Texas, there's good news-bad news about bald eagles: they're not classified as "endangered" but they do remain on the "threatened" list. If you want to see one, don't drive all the way to Alaska. Just sit high on a rocky ledge overlooking the Brazos River on a cold January day and sooner or later, one might just come drifting by and if that won't make you heart leap, nothing will.

Until next time - I'll see you down the road and God Bless America!



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