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Date: Wed Apr 12 18:07:37 2000
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Subject: SALMON-GOBBLING TERNS POSE BIG PROBLEM FOR
BIOLOGISTS
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SALMON-GOBBLING TERNS POSE BIG PROBLEM FOR BIOLOGISTS
(The Columbian)
ASTORIA, Ore. - Government biologists have decided the
Caspian terns that moved onto a human-made island in
the Columbia River and began feasting on millions of
young salmon have to go.
But where to send them?
With more salmon runs up and down the West Coast going
on the endangered species list, the team looking for
alternative nesting areas for the voracious birds has
run into the kind of reaction they might expect from a
nuclear waste dump. "It is a 'Not In My Backyard' sort
of issue," said Bob Willis, a biologist with the U.S.
Army Corps of Engineers. Problems began about a dozen
years ago when Caspian terns discovered Rice Island, a
220-acre lump of dredged sand located about eight
miles
from the mouth of the Columbia.
>From a tern's point of view, it is paradise: lots of
bare sand on which to lay their eggs and a veritable
buffet line of young salmon swimming by on their way
to the ocean. And unlike the natural islands in the
Columbia, the sandy parts don't flood in the spring.
But from the salmon point of view, it's like reaching
the next level on a video game. They have just
survived the gantlet of hydroelectric dams, with their
grinding turbines and long stretches of slackwater
filled with hungry northern pike minnows, only to be
swooped down
upon by screaming terns.
As historic nesting sites, mostly inland, have
succumbed to fluctuating water levels, development,
encroaching vegetation and even growing numbers of
eagles, Rice Island kept getting bigger, and so did
the
numbers of terns. They now number some 20,000, making
them the largest nesting colony of Caspian terns in
the world, according to the Pacific Seabird Group.
The colony represents a quarter of the North American
population and three-quarters of the West Coast
population. But the salmon they eat are in trouble.
More than $3 billion has been spent trying to restore
dwindling Pacific salmon populations, and the
government is considering breaching four hydroelectric
dams on the Snake River to improve young salmon
survival on their migration to the sea.
The 80 million young salmon and steelhead that swam
down the Columbia River this year included 11 groups
on the endangered species list and represented an
investment of more than $500 million.
Based on observations and the collection of some
40,000 coded wire tags injected in salmon before they
were released from hatcheries, biologists figure the
terns on Rice Island ate as many as 20 million salmon
and steelhead, or about 25 percent of the total, said
Ben Meyer, a National Marine Fisheries Service
biologist and chairman of the group of government
experts who will recommend what to do with the terns.
Details are still being debated, but the members of
the group agree that the terns have to go from Rice
Island.
Attempts to make Rice Island less attractive by
planting winter wheat on the bare sand nesting areas
last winter were foiled by heavy rains.
But biologists are confident they have a better plan.
They will string great swaths of bright orange plastic
snow fence across the open sands so the terns won't
want to nest there.
They like open spaces and the snow fence will cut off
their view. ATV patrols will roar around to scare off
any diehards. Luring the birds to new nesting sites is
no problem, either. This summer, the Caspian Tern
Relocation Project successfully lured a couple
thousand terns to East Sand Island, near the mouth of
the Columbia, by setting out tern decoys and playing a
recording of the croaking calls that ecologist Don
Lyons describes as the " Caspian Tern Greatest Hits."
Because they are closer to the mouth, where there are
more ocean fish, the terns' diet consisted of only
about 50 percent salmon and steelhead, compared to
about 80 percent at Rice Island, Meyer said.
The ideal would be to create many new nesting colonies
up and down the coast, so each one would be have only
a
couple hundred birds and the impact on fish would be
small. But Oregon isn't interested in any more sites.
And though Washington has agreed to look, it won't
allow any that hurt a threatened or endangered run of
salmon, said Herb Pollard, a NMFS biologist based in
Boise who also serves on the working group.
"They are just about as welcome as morning glories in
your garden," Pollard said. Washington Department of
Fish and Wildlife biologists are considering some
islands in Grays Harbor, where terns used to nest, and
hope to find another in southern Puget Sound. "I'm
convinced we will be able to find places to assure the
long-term survival of terns in the Northwest, and
still
not jeopardize salmon and steelhead," said Fred
Dobler, southwest regional wildlife program manager
for the department. "It won't be easy."
JEFF BARNARD, Associated Press writer
Copyright 1999 The Columbian Publishing Co.
JEFF BARNARD, Associated Press, SALMON-GOBBLING
TERNS POSE BIG PROBLEM FOR BIOLOGISTS.,
The Columbian, 09-12-1999, pp Clark Coun.
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