Racing
the oil sheen, biologists take a bird census: A team on
Point Au Fer Island, LA, is counting the populations of
migratory birds before oil comes ashore.
By
Louis Sahagun, Los Angeles Times
June 22, 2010
Reporting from Theriot, LA
The dozen biologists
on Point Au Fer Island were on an 11th-hour mission to count
what
was there before it was gone.
Nearly two months into the Deepwater Horizon oil disaster,
which has dumped millions
of barrels of oil into the Gulf of Mexico, they were counting
birds guarding chicks and
eggs. Trying to ignore the sweltering heat and stinging
deer flies, the biologists strode
across the island's remote beaches and sandbars for two
days last week to take stock of
avian life before oil comes ashore.
Essentially, they wanted to estimate the populations of
American oystercatchers, common
nighthawks, least terns, Wilson's plovers and other species
for use in charting what they
fear could be a drastically downward trend over the next
several decades.
Environmentalists are wary that a shift in weather and ocean
currents will bring oil and
toxic chemicals from the breakdown of petroleum into Atchafalaya
Bay, about 75 miles
southwest of New Orleans.
The data collected during the two-day survey may help answer
crucial questions at the
heart of the disaster: What effect will oil and dispersants
have on one of the nation's
biggest breeding grounds for birds, and how long will it
take to recover? Or will it?
"There is a sense of urgency to get remote places like
this thoroughly surveyed before the
oil hits," said Steven Cardiff, collections manager
of birds and mammals at Louisiana
State University's Museum of Natural Sciences. "A high
tide with oil and a strong wind,
and it's all gone."
The oil slick has already despoiled coastal estuaries a
few miles east of this 20-mile-long
island, killing untold numbers of birds, fish, turtles and
mammals, and ruining their
delicate bayou habitat, perhaps for years to come. Compounding
problems, cleanup crews
using booms, earth movers and shovels have inadvertently
crushed nests, eggs and newly
hatched chicks.
Against a backdrop of oil rigs rearing skyward, the island's
windswept shores were
strewn with clutches of speckled gray eggs resting in slight
depressions in the sand amid
broken oyster shells.
Scads of fiddler crabs — a favorite food of Wilson's
plovers — scuttled across mud flats
pocked with tracks of coyotes and raccoons. Butterflies
flitted over knee-high grass. Male
nighthawks swooped under roiling thunderheads. On all sides,
the air was filled with bird
calls: the throaty trills of orchard orioles, the raspy
calls of terns bringing fish to their
demanding young.
The team scanned the sun-baked ground to avoid crushing
eggs or chicks under their
boots. Adult birds tried to lure the human intruders away
from their nests by pretending
to have broken wings, or diving low over their heads.
Team member Steve Liptay, assistant director of Coastal
Bird Conservation, a nonprofit
organization dedicated to research and survey work, jotted
down every sighting —
species, location, date, time — on a clipboard.
"Some people are proposing that surveys like this one
be conducted every 10 days in
order to track the impacts as closely as possible,"
Liptay said. "At the very least, I hope
we can return soon with signs to warn people away from known
nesting sites."
A few yards away, as Cardiff made his way along the shoreline,
he spied a dark glob just
a few inches away from a least tern nest harboring a single
egg.
His face fell. "It's a tar ball," he said, shaking
his head.
By the survey's end Wednesday, team members had trudged
across 30 miles of beaches
and counted roughly 120 pairs of Wilson's plovers, 500 pairs
of least terns, 750
individual nighthawks and six pairs of American oystercatchers.
Habitat for these and many other migratory birds was already
in distress long before
crude oil began bursting from BP's blown-out well on April
20. Louisiana loses about 25
square miles of coastal marshlands each year because of
development, petroleum
exploration and altered flows of Mississippi River sediment.
The survey was only one of many studies started in recent
weeks by environmental
organizations, Louisiana State University and state and
federal agencies to track the oil's
destructive force.
"The whole ecological system is falling apart,"
said Richard DeMay, senior scientist with
the Barataria Terrebonne National Estuary Program, and captain
of one of two vessels
used to ferry biologists to the shores of Point Au Fer Island.
"This survey and others will help us get a handle on
what we have out there now, and
what we may lose over time," he said. "Scientists
will be studying the results for years to
come."
louis.sahagun@latimes.com
Copyright © 2010, The Los Angeles Times
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