
By Bonnie S. Lawrence
High in the summer sky, a torpedo-shaped hunter beats the air with long
pointed wings, then tilts downward, and goes into the most spectacular
dive a bird can make. Wind moves over the feathers as the bird gains
speed pursuing a fleeing pigeon. Wings half-folded, it drops with an
attack speed that can reach 200 miles (320 kilometers) an hour. The bird
strikes its prey in mid-flight, killing it with the impact from its
outstretched talons. The peregrine falcon has returned to the coast of
Maine.
For centuries the peregrine falcon ruled the air near the top of
the food chain. Nest-robbing, trapping, and shooting contributed to a
decline in numbers, but the real threat came with the wide-spread use of pesticides. Chemicals such as DDT worked their way up the chain to
predatory birds; these birds of prey ingested pesticides with their kill
and built up high levels of chemicals in their bodies. Eggs failed to
hatch or the thin shells broke under the weight of the parents bodies.
A survey in 1964 failed to find a single peregrine falcon nest east of
the Rockies. In 1970 the bird was declared an endangered species.
In 1984 park officials at Acadia joined in the effort to restore this bird
to the wild. Scientists bred adult birds in captivity; their eggs were
hatched in the laboratory. Chicks three to four weeks old were placed
in artificial rearing nests called hack sites, mounted along a cliff.
Bars across the front of the box allowed the falcons to see out and
protected them from predators. The fledglings were fed through a long,
sloping tube to prevent their associating food with humans. When the
wings were mature and strong enough for flight, the birds were released
into the wild. In 1986, 22 peregrine falcons were successfully hatched
on a cliff face overlooking Acadias Jordan Pond. Adult peregrine falcons began
returning to the park and 1991 marked the first successful nesting in
35 years. Three chicks were sighted. Every year since, a pair have
returned, raising three or four chicks. In 1995 a second pair of
peregrine falcons also raised a chick.
Each year early in spring, park
scientists search for signs of the peregrine falcons return. Hiking
trails around the nest sites may be closed to visitors to protect the
young birds. Officials hope that the peregrine falcons will continue to
return home to raise their young in Acadia National Park.
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© 1997 National Geographic Society. All rights reserved.
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