College researchers studying avian trends
here
Willowbrook Park serves
as a working classroom for CSI biology team as it studies bird
populations
Staten Island Advance - Sunday, December 10, 2006
 College
of Staten Island professor Tom Brown stood quietly as he waited, at
a distance, for birds to fly into a net he set up in Willowbrook
Park on a chilly morning in October.
But this day, the net, which allows Brown and
college researchers to catch migrating and breeding birds to track
their size, weight, age and health, didn't produce any results
before it was time to take it down.
"Some days you get nothing," he said, adding that on
other days, you might get close to 100 birds in the course of a few
hours.
The project, part of the U.S. Fish and Wildlife's
Monitoring Avian Productivity and Survivorship program, helps
determine how factors such as urban sprawl and pesticide spraying,
meant to combat the West Nile virus, impact migratory and breeding
bird populations.
The research also could produce evidence of avian
flu; swabs of excrement and feather samples from all birds caught
are sent to a laboratory at the University of California in Los
Angeles to be tested for the virus.
If the tests yield positive results, an analysis of
the birds' isotope makeup can help determine which region they
migrated from, leading health officials to potential sources of the
bird flu.
"If any of our samples came back as positive, they
may be able to trace exactly where the birds were picking up the
virus," said Brown, chief science technician and a biology professor
at the Willowbrook school.
"You want to see if there's a reservoir where the
virus is incubating."
The CSI project, which began in 1997, is only one of
more than 1,000 sites across the United States where avian trends
are studied. Besides the Willowbrook Park site, CSI professors and
graduate students conduct sampling at Corson's Brook Woods, off
Richmond Hill Road in Willowbrook, Buck's Hollow in the Greenbelt
and Fort Tilden, off Rockaway Beach in Queens.
This year, the program is funded by an $18,000 grant
from Con Edison.
In the nine years the project has been active, Brown
said he's noticed a decline in the population and breeding of song
birds -- such as scarlet tanagers and eastern wood-pewees -- that
come through Staten Island but an increase in larger birds like
red-tailed hawks.
EXPLOSIVE BUILDING
The explosive building in the borough over the last decade has made
woodlands, where the birds breed, more scarce, making it less
attractive to songbirds, Brown said. And when they do come, they
often breed less, he added.
"Birds, at one time, didn't have to travel as far to
rest and eat," Brown said. "The amount of energy that they expend
increases. It could be when the birds reach (the woods), they've
expended so much energy on migrating that they don't put as much
energy into reproduction."
As for the red-tailed hawks -- exemplified by famed
birds Pale Male and Lola in Manhattan -- they've grown more
accustomed to living in urban areas, Brown said.
Besides Brown, CSI students and graduate students
from the City University of New York's Graduate Center in Manhattan
participate in the study.
"You're taking the pulse of the environment but you
need to look at it on both local and global scales," said graduate
student Jarrod Santora about the Willowbrook Park study. "This is a
very local focus."
Full results of this year's sampling won't be ready
until the results have been analyzed by next spring.
Dick Veit, chair of CSI's biology department, said
it's necessary to keep tabs on how bird populations are affected to
see if they're adapting to changes in nature or if they are
declining in numbers.
"In any given year, (the goal is to see) how are the
birds doing in terms of producing baby birds," Veit said, adding
that researchers put out the nets every 10 days and monitor them for
six hours at a time.
In addition to being weighed and measured, Veit said
the birds are banded so that researchers elsewhere in the country
can note where the birds migrate to and from and enter the
information into a centralized U.S. Fish and Wildlife database for
analysis.
"You can trace migratory paths of these birds," he
said. "A critical thing here is gauging how fast the population is
growing or declining."
 Con
Edison spokesman Mark Irving said CSI's program is an indicator of
how the Island's growing population is affecting avian life here.
"It sheds more light on how important it is to
preserve woodlands and wetlands and (birds') natural habitat,"
Irving said.
"We've reached a point where we're running out of
space to expand. We've got to, as much as we can, work to preserve
these type of environments."
By Glenn Nyback
Reprinted here with permission
from the
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