|Subj:||Mysterious death of Lake Erie fish puzzles scientists|
|Date:||8/16/01 3:52:19 PM Pacific Daylight Time|
Mysterious death of Lake Erie fish puzzles scientists
By CAROLYN THOMPSON
Associated Press Writer
August 16, 2001
DERBY, N.Y. -- Thousands of dead fish are washing up on Lake
Erie's eastern shores and while there are plenty of
theories, the cause of the alarming kill is unknown.
"It's a very interesting mystery," said Bill Culligan, an
aquatic biologist who heads the state's Lake Erie Fisheries
Research Station in Dunkirk.
The fish carcasses, mostly sheephead, but also bass,
stonecats and a few endangered sturgeons, rot in coves and
on beaches, the stench forcing homeowners to close their
windows to the lake breezes.
Culligan said scientists are looking into whether a virus,
bacteria, weather-related events or, indirectly, zebra
mussels may be to blame. Several near-dead sheephead were
collected Wednesday and sent for analysis to labs at Cornell
University and the state Department of Environmental
Conservation, near Albany.
Until recent cooler weather, oppressive heat had led most
fish to die and decay too quickly to test.
"One problem we've had testing is you need very fresh fish
to do cultures," Culligan said.
Lab results are expected in one to two weeks.
The kill has been steady through the summer in the eastern
third of the lake, from Ontario, Canada, through New York
and into Pennsylvania, authorities said. While impossible to
put a number on the deaths, it is estimated to be well into
Jeff Connors runs along the Evans shore, about 15 miles
southwest of Buffalo, in the mornings. While dead fish are a
fairly common sight at the end of the summer, he said,
"there's never this much, and never so early."
"You've got to watch where you're stepping," he said.
At the Sturgeon Point Marina in Derby, the smell of dozens
of decaying fish visible along a short stretch of beach
invades the air with shifts in the wind.
"It's bad but it comes and goes," said Jennie Smaldino of
Evans, who along with Connors, works a hot dog stand at the
Culligan said scientists first attributed the deaths to
weather-related events called upwellings, during which
strong winds blow the warmer surface water to the other end
of the lake and deeper, colder water comes to the surface. A
July 27 upwelling, one of three recent events, dropped the
lake temperature in Dunkirk 23 degrees in a matter of hours,
"But fish are also dying at other times," he said, so
scientists look for other explanations.
The round goby fish, a recent lake invader, is one suspect.
One of the few fish to feed on zebra mussels, the gobies
are, in turn, eaten by sheephead and the other bottom
feeders now dying in droves, Culligan said.
"Until the round goby showed up, nothing ate the zebra
mussel," he said.
Lake residents have their own theories. Betty Maslow of
Point Breeze wondered whether the lower lake level has
played a role in water quality and temperature.
"Our beach is twice the size it was last year," she said.
The fish die-off has led to the deaths of a smaller number
of seagulls and other scavengers. The birds die from a type
of botulism, a toxin which forms as the fish decay.
Environmentalists fear more birds, including migrating
loons, will fall victim to botulism if the fish die-off
continues into the colder weather. Last year, a different
strain of botulism killed more than 8,000 water birds along
Lake Erie in late fall.
Until a cause for the fish kill is known, authorities advise
against eating undercooked fish from the lake.