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Eagles and Buzzards
Nature Bulletin No. 245-A November 19, 1966
Forest Preserve District of Cook County
Seymour Simon, President
Roland F. Eisenbeis, Supt. of Conservation
EAGLES AND BUZZARDS
Until the Bald Eagle was adopted as our national emblem of freedom
by the Second Continental Congress in 1782, an eagle had been the
emblem of conquerors. It was engraved on tablets and seals of kings
who ruled more than 6000 years ago. It was regarded with reverence by
the ancient Greeks and later by the Romans who made it the emblem of
their republic and, later, of the Roman empire. As a silver bird on a tall
standard it was carried at the head of every legion in their armies.
All birds of prey have the most highly developed organs of vision in the
world. In most kinds the eyes are so large that the two eyeballs occupy
more space in the skull than does the brain, and are equipped with many
special muscles so that the eye can be instantly transformed from a
telescope to a microscope. There is a record of a bald eagle, soaring at
great height over a big lake, diving diagonally downward to pick up a
floating fish three miles away.
Of about 80 species of eagles known in the world, we have three in
North America: the Southern Bald Eagle, the slightly larger Golden
Eagle, and the Northern Bald Eagle which breeds in northern Canada
from Alaska to Labrador. The latter, with the exception of the
California Condor which is nearly extinct and has a wingspread of from
9 to 11 feet, is our largest bird of prey. A peculiarity of these eagles is
that the females average somewhat larger than the males.
A few southern bald eagles are seen near Chicago every year, usually
during the fall or winter. In October, 1949, five were seen soaring over
our Palos preserves, wheeling in great overlapping circles high in the
sky. This eagle feeds principally on fish, both alive and dead, and
frequents the shores of lakes and large rivers. They formerly nested
among the Indiana dunes and in the great Kankakee Marsh. The nest is
built high up in a big tree, never very far from water, and is a huge
bulky mass of large sticks with a shallow bowl of finer material. Eagles
are presumed to mate for life and occupy the same nest year after year,
adding to it each spring, when the female lays two, rarely three, ivory
white eggs.
The head, neck and tail of the adult is pure white, the body being sooty
brown and the wing nearly black. Immature bald eagles, however, until
they are three years old and become adult, are dark-feathered
throughout and greatly resemble the Golden Eagle, a bird of the wild
mountainous countries which has been seen soaring over the Chicago
region on rare occasions in recent years.
Another big bird seen here almost every year and sometimes mistaken
for an eagle, is the Turkey Vulture or Turkey Buzzard. The buzzard,
however, has a shorter neck, a much smaller head -- naked and covered
with red wrinkled skin -- and soars with its wings tilted slightly upward
in a broad wide V; whereas the eagle's wings are outstretched in almost
a straight line. In fair weather the buzzard, a big ugly blackish bird with
a wingspread of nearly 6 feet, can soar for hours, slowly circling on
motionless wings. Sometimes one rides an updraft in ever-widening
spirals until it is a mere speck in the sky. From such heights, with its
marvelous vision, it can detect a dead animal as small as a rabbit and
swiftly descends to feast upon the rotting carcass which it tears apart
with its powerful hooked beak. They make no nest but lay two, rarely
three, eggs in a hollow log, a brushpile, an old stump, among rocks or
in a cave. The filth they eat is disgorged to feed their young, which are
even more ugly and revolting than their parents.
On pay day the eagle screams.
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