By Roger Witherspoon
The Journal News (Westchester County, NY)
October 23, 2002 Wednesday
Audubon Society: 201 species near endangered status
The Journal News
NEW YORK - Bird populations throughout North America are steadily dropping
because of lost habitats and other factors, and a quarter of them are approaching
the status of endangered species, according to a new National Audubon Society
report.
"One in four species that we know across the United States are at risk," Frank Gill,
the society's chief ornithologist and senior vice president for science, said yesterday.
"This cuts across all groups of birds, from songbirds to water birds to raptors."
The society released a watch list containing 201 species of North American birds
whose numbers have dwindled over the past 40 years to the point where they could
soon become endangered. The list is a compendium of data compiled from bird-
breeding studies conducted by the U.S. Fish and Wildlife Service and the annual
Christmas bird count conducted by 71 million Audubon volunteers across the country
in 2001.
A society analysis of annual studies since 1966 found that loss of habitat, disease,
continuing development in forest and wilderness areas, and chemical contamination
has taken a toll on many species.
The society found, for example, that the ranks of the forest-dwelling olive-sided
flycatcher, which has been common in Westchester, Rockland and Putnam counties,
has declined by 70 percent since the 1960s. These birds, Audubon spokesman John
Bianchi said, "need deep forest and that is harder and harder to find. These birds will
not go near an area where the sunlight hits the forest floor. Clearing brush for a
home will eliminate quite a bit of area from the bird's use."
Other birds common to this region also are declining. Populations of the American
woodcock are down 48 percent, the blue cerulean warbler has declined 80 percent,
the prairie warbler 44 percent, and the golden-winged warbler has left the state,
according to the Audubon survey. The watch list, which lists birds by degree of
decline and region, is on the society's Web site at www.audubon.org.
There is another factor harming birds like the olive-sided flycatcher, which nest in
ground cover and low bushes. They are competing for dwindling floor space with
other animals.
"There are issues with the growing deer population," said Jack Robbins, Westchester
County's deputy commissioner of parks, recreation and conservation. "There are
more deer in smaller areas and they eat the ground cover these birds need."
Efforts to improve habitats for many animals has had mixed results in recent years,
Robbins said, as increasing development has collided with efforts to improve wildlife
habitats.
"Because of the drop in the pesticide DDT, several birds and animals are coming
back to this area," Robbins said. "The coyotes have come back, the wild turkeys
have come back, the bobcats are back. That's the positive thing in this region."
But the dwindling amount of undeveloped land means there is competition for what
is left. "Canada geese have driven out a lot of the waterfowl that bird lovers want to
watch," said Robbins, himself a bird-watcher. "They are more aggressive and
accommodate easier to human habitats such as lawns and mowed areas."
Raptors have also enjoyed a resurgence in the area, though one species, the short-
eared owl, has lost 80 percent of its population. That owl eats small rodents in
grassland areas, and has been hurt by development and rat poisons, Bianchi said.
Many raptors have adapted to encroachment and improvements in the environment.
Paul Kupchok, director of the Green Chimneys farm and wildlife center in Patterson,
said the number of raptors in this area was "way up" because of the decreased use
of pesticides.
"There are more peregrine falcons than ever before with a pair nesting on every
bridge over the Hudson River between Manhattan and Albany," Kupchok said.
"Raptors are all over the place. Bird feeders in this region have become dining tables
for hawks and falcons."
But Eugene Herskovics, a Rockland County park ranger, said that volunteers have
been conducting a county "hawk watch" since 1975, and that the overall numbers
have steadily dropped.
"In the '70s, the numbers were around 20,000," he said. "But since 1991, for the
most part, they have been under 10,000 each year."
Different species of raptors have reacted differently to the pace of development in
the Hudson Valley, Herskovics said. Rockland's hawk watch spotted only eight bald
eagles in 1986, but last year counted 54.
"The peregrine falcons are doing pretty well here, too," Herskovics said. "They have
adapted to the tall buildings. But there are others that can't change as easily with
the times.
"When I grew up, there were a lot of farms here and a lot of ringneck pheasant,
which were introduced to the area in the 1850s," he said. "But there are only about
three farms left in the county, and they no longer have their required habitat. There
are very few pheasant left in the county. There are some species we may lose
entirely."
Reach Roger Witherspoon at rwithers@thejournalnews.com or 914-696-8566.
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