Biologists take steps to save the Higgins' eye
By Ann McGlynn
The biologists call it the Clam Palace. For the
Higgins eye pearlymussel, it might mean survival.
The simple pole barn in western Wisconsin with the
fancy name, along with mussel beds like the one near
Cordova, Ill., that biologists say is one of the best,
is the epicenter of an effort to save the native
Mississippi River mussel with a long name and a
shrinking chance for survival.
A mussel, they may seem boring to a lot of people,
said Scott Gritters, an Iowa Department of Natural
Resources, or DNR, biologist working with the Genoa
Fish Hatchery in Wisconsin on the mussel recovery
project. But mussels can tell you over the long haul
how good the water is. Theyre telling us it is not
Gritters and the other biologists working on the
project are implanting thousands of baby mussels onto
fish growing on fish is one important part of the
mussel life cycle and releasing those fish and
mussels into several areas in Iowa, Minnesota,
Wisconsin and Illinois.
Their hope is that the pinhead-sized baby mussels will
mature on the fish, drop off and grow into fist-sized
adults in mussel beds that will be able to survive
well into the future. A Higgins eye can live more
than 70 years if they survive.
Time is not on our side, Gritters said of the
declining population of Higgins eye pearlymussels.
Zebras vs. Higgins eye
The Higgins eye is usually found in areas with deep
water and fast currents, according to the U.S. Fish
and Wildlife Service. They bury themselves in the
river bottoms with the edge of their partially opened
shells exposed. They siphon water for food such as
algae and bacteria as the water flows over them.
The mussels flowing habitat was affected when locks
and dams were built, Fish and Wildlife officials say.
They also have been affected by chemicals in the river
and the dredging to keep the river channel open.
The Higgins eyes biggest enemy, though, might be the
zebra mussel, a tiny mussel that came to the Upper
Mississippi River from the Black and Caspian seas in
the early 1990s, reportedly in the ballast water of
ships, officials say. The zebra mussel attaches itself
to other mussels, including the Higgins eye, and
Higgins eye pearlymussels never have been the most
abundant species of mussel, biologists said. The
mussels were placed on the endangered species list in
The infestation of the zebra mussel made the Higgins
eyes existence even more precarious. At the same
time, other mussels also began to decline, Fish and
Wildlife officials said.
Not only do the Higgins eye show biologists how the
water quality is, they also provide food for fish and
other river animals.
They are the snack food of the aquatic world, kind of
like a taco chip, said Roger Gordon of the Genoa Fish
Work at the palace
Higgins eye mussels are taken to the fish hatchery
each spring, where they are placed into a bucket with
fish, Gordon said. The young mussels, called
glochidia, implant onto the fish. Some of the fish
eventually are released into the wild, while others
stay at the hatchery to allow the mussels to fully
grow and drop off the fish. Those mussels then taken
to places where the zebra mussels are not.
Were trying to put these mussels where there arent
zebra mussels, he said. Theres no use of throwing
them right back into the battlefield.
In Iowa, zebra mussels are not found in three
tributaries of the Mississippi River the Iowa,
Wapsipinicon and Cedar rivers, Gritters said. In the
spring, biologists hope to implant Higgins eye from
the Cordova mussel bed into fish captured in those
three rivers. The fish then will be released.
Other tactics are being employed in the other states
involved in the project.
All of our eggs are in the Mississippi River and we
need to spread them out, Gordon said. We dont know
if this is going to work or not, but between all of
our efforts, I think were going to get them to places
where they can thrive.
Millions of dollars were made off the harvesting of
mussels, growing towns and keeping them alive with
industries like the pearl button industry, Gordon
said. There is kind of a debt to these animals.
Theres a whole other world out there that lives on
the bottom that was a very important part of peoples
lives in this part of the country, he said.
This project is paid for with money from the U.S. Army
Corps of Engineers, the Fish and Wildlife Service and
the states, he said.
It will take years to determine whether efforts to
boost the Higgins eye population will pay off, he
said. No one knows for sure what the outcome will be,
but he acknowledges that there is a challenge ahead.
Were getting into the game really late, he said.
The building is already burning
Here's the link to the original story and pictures
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