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Audubon Pennsylvania
News >
Disappearing Common Birds Send Environmental
Wake-Up Call
Audubon Analyses Reveals Dramatic Declines
for Some of Pennsylvania’s Most Familiar Birds Harrisburg,
PA Thursday, June 14, 2007 –Population declines for some
of the most recognized and beloved birds in Pennsylvania echo
the disturbing findings of a new analysis by the National Audubon
Society that reveals how local and national threats are combining
to take a toll on birds, habitat, and the environment across the
country.
“These are not rare or exotic birds
we’re talking about—these are the birds that visit
our feeders and congregate at nearby lakes and seashores and yet
they are disappearing day by day,” says Audubon Chairperson
and former EPA Administrator, Carol Browner. “Their decline
tells us we have serious work to do, from protecting local habitats
to addressing the huge threats from global warming.”
The national study found that continental
populations of some common birds nosedived over the past forty
years, with several down nearly 80%. In Pennsylvania, the golden-winged
warbler, the eastern meadowlark, and the wood thrush top the state
list, with declines between 62 and 98 percent. Golden-winged warbler
and wood thrush populations elsewhere in the country have not
experienced such dramatic declines. However, Pennsylvania’
fragmented and overbrowsed forests provide nesting habitat for
approximately 8.5 percent of the world’s wood thrushes and
nearly 9 percent of the golden-winged warblers. The eastern meadowlark
has experienced a 72 percent decline nationwide compared with
an 86 percent decline in Pennsylvania, largely due to the widespread
loss of the state’s family farms, which provided large open
tracts of field space. The pronounced national declines are attributed
to the loss of grasslands, healthy forests and wetlands, and other
critical habitats from multiple environmental threats such as
suburban sprawl. The study notes that these threats are now compounded
by new and broader problems including the escalating effects of
global warming and demand for corn-based ethanol.
“Here in Pennsylvania, the biggest culprits
are habitat fragmentation, a white-tailed deer herd out of balance
with the rest of the ecosystem, and suburban development,”
says Dr. Timothy Schaeffer, Executive Director of Audubon Pennsylvania.
“Fragmented forests become susceptible to non-native pests
and diseases, making them unsuitable for wood thrushes. Deer overbrowsing
hinders forest regeneration and results in poor cover for ground-
and understory-nesting birds. This lack of early successional
woodland affects ruffed grouse and golden-winged warblers. Meanwhile,
grassland birds like eastern meadowlarks are declining due to
development of farmland and changing agricultural practices. Finally,
while Audubon supports well-sited wind power, we are unsure of
the potential impact that wind turbine sites along our prominent
forested ridges will have on the millions of migratory birds that
use those ridges as flyways.”
Considering these multiple factors, the five
species especially hard hit in Pennsylvania include:
- Golden-Winged Warbler is suffering from loss of suitable
successional habitat, dense shrubs and young saplings, due to
reforestation and development. The species, down 98 percent
in Pennsylvania, also faces competition from the closely-related
blue-winged warbler, which is expanding its range to the north.
- Eastern Meadowlarks, down 86 percent across the state,
are threatened by the loss of farmland and changing agricultural
practices. Further, the potential conversion of acres currently
protected for conservation to biofuel crops like corn puts both
eastern and western meadowlarks at even greater risk.
- Wood Thrushes rely on large interior forests and are
threatened by habitat fragmentation, deforestation and nest
parasitism. Each year wood thrushes, down 62 percent in Pennsylvania,
migrate from Central America to the U.S., where Pennsylvania
houses 8.5 percent of the world’s breeding population.
- American Bittern populations nationwide are declining
significantly, 59 percent in the last 40 years. The main threats
faced by the species are degradation of wetland habitat from
invasive plants and diminished water quality, as well as development.
This species uses Pennsylvania’s wetlands as stopovers
during migration while a small number continue to reside here
throughout the breeding season.
- Ruffed Grouse, down 22 percent statewide, are found
in young open mixed deciduous-coniferous forests. Pennsylvania’s
official state bird, the ruffed grouse is dependent on successional
habitat. Loss of forests to development and the loss of old
fields as forests mature are key threats, while overbrowsing
by deer makes some early successional forest less suitable for
the species.
Pennsylvanians care deeply about birds and
their habitat, and Audubon Pennsylvania is working with individuals
and organizations across the state to monitor bird populations
and promote sound stewardship on the ground. With the majority
of land in Pennsylvania in private ownership, Audubon Pennsylvania
is hard at work engaging landowners with advice and assistance
for creating bird-friendly environments on their properties. “Our
Audubon At Home program is offering private citizens, educational
facilities, and business campuses the tools to better manage their
land as bird habitat,” says Schaeffer. “Also, Pennsylvania
was the first state in the nation to designate Important Bird
Areas (IBAs). Today, Pennsylvania boasts 84 Important Bird Areas,
and our staff — with the help of local Audubon chapters,
private landowners, and partnering organizations — is implementing
conservation plans that will help protect and restore critical
bird habitats within these IBAs.”
Audubon’s State of the Birds: Common
Birds in Decline list stems from the first-ever analysis combining
annual sighting data from Audubon’s century-old Christmas
Bird Count program with results of the annual Breeding Bird Survey
conducted by the U.S. Geological Survey. “This is a powerful
example of how tens of thousands of volunteer birders, pooling
their observations, can make an enormous difference for the creatures
they care the most about,” says noted natural history writer
and Pennsylvania resident Scott Weidensaul. “Thanks to their
efforts, we have the information. Now all of us — from birders
to policy makers — need to take action to keep these species
from declining even further.”
Public response will shape the long-term outlook
for Pennsylvania’s Common Birds in Decline. “Fortunately,
individuals can still make a difference,” says Schaeffer.
“I encourage people to visit our web site or contact their
local Audubon chapter to find out what they can do to help. Audubon
Pennsylvania offers a wealth of resources for conserving our natural
world. Healthy bird populations are the result of a healthy environment,
and a healthy environment improves the quality of life for all
Pennsylvanians.”
Click here
to view the Pennsylvania fact sheet.
More information about Audubon’s Common
Birds in Decline analysis is available at www.audubon.org.
In addition, journalists may visit Audubon’s online press
room at www.audubon.org/news/pressroom/CBID.
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