Here's a copy of an article that ran in last Friday's Grand Rapids
Press. It also featured one of Steve Pothoven's now famous pictures of
Hemimysis, but I couldn't get it by email.|
* * * *
invader might threaten the Great Lakes
|Subhead (if any)
||Ship's ballast water likely to blame for arrival of
||Howard Meyerson /
Press Outdoors Editor
|Correction Date (if any)
|Correction Text (if any)
|Text of Story
||Federal authorities with the National Oceanic and
Atmospheric Administration want Lake Michigan anglers and boaters to
keep an eye out this summer for the most recent invader, a tiny
crustacean known as Hemimysis anomala, or bloody-red shrimp.
"We've decided to get the public involved looking for the organism,"
said Dave Reid, director of the Ann Arbor-based National Center for
Research on Aquatic Invasive Species. "Its swarming behavior is very
unique -- like a cloud of gnats in the water. No other water species
"If people see a strange phenomenon that looks like reddish-tinged
insects but underwater, we want them to contact us and give the date
and the location."
The tiny shrimp, native to the
Black and Caspian seas, was discovered last November in the U.S. Coast
Guard basin along the Muskegon channel off Lake Michigan. Experts
suspect the shrimp arrived in the
ballast water of a ship.
The finding was the first official report of the red
invader turning up in U.S. waters. Officials say it also was discovered
off Oswego N.Y. on Lake Ontario in the spring of that year, but was not
reported until December.
Reports have since trickled in from other locations. Reid received two
recent reports from scientists looking for the shrimp.
It was found in the stomachs of white perch caught in Lake Erie off
Port Dover, Ontario. A second, unconfirmed report, has them in the
stomach of a brown trout caught in Wisconsin waters on Lake Michigan.
"We can't verify the second finding," said Reid. "This one had been
feeding on shrimp, but we can't
verify it because there is a native form of the shrimp
in the Great Lakes.
The bloody-red shrimp is named for
its red markings and the red cloud it creates underwater when
thousands may swarm during the summer and fall. It is a shallow-water
denizen, often found in 30 feet of water or less and close to shore.
It belongs to a family of shrimp-like crustaceans known as Mysidacea or
mysids. Native mysids in Lake Michigan are a deepwater species usually
found offshore as deep as 150 feet. They also lack the colorful
markings of the bloody-red shrimp.
Officials say the impact of the new shrimp
is unknown. It is thought to be a high-energy food for alewives and
perch and may turn out to be a rich food source for those fish.
But red shrimp
also feed on the same zooplankton that larval fish need to eat.
Scientists speculate that it has the potential to compete with young
fish and cripple a population.
"It's a double-edged sword and we don't know where the balance is,"
said Steve Pothoven, a NCRAIS fish biologist who runs the Muskegon
field office at the Coast Guard basin.
"Some people think it will really be an issue, both as a zooplankton
predator and contaminant transport, but not everyone buys that. So far
no one has reported any impact on their fisheries."
What is known is that the bloody-red shrimp
has moved around the world, spreading from its Russian origins. It is
reported to have moved across the waters of Europe and arrived in the
United Kingdom in 2004.
"We strongly suspect that it's in more than the locations reported so
far," said Reid. "It's much too easy for it to get sucked up in ballast
water and bait buckets."
Reid said his group is trying to ramp up surveillance for the creature.
It has been working with scientists around the region, the shipping
industry, various ports and state and federal agencies. Two sampling
teams have been established: one on the eastern Lake Michigan shoreline
led by Pothoven, the other working from Saginaw Bay down to Lake Erie.
David F. Reid, Ph.D.
Director, NOAA National Center for Research on
Aquatic Invasive Species (NCRAIS)
Senior Research Scientist, Nonindigenous Species Program
U.S. Department of Commerce
National Oceanic and Atmospheric Administration
Great Lakes Environmental Research Laboratory
2205 Commonwealth Blvd.
Ann Arbor, MI 48105-2945
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