Spin the wheel and from New Zealnad in ship ballest comes an invasive snail species without any natural predator into the Great Lakes again:
Editorial: Every new alien species poses new risk to Lakes
Before 1988 only a handful of Michigan residents likely knew — or cared — what a zebra mussel was. What would happen if a few were dumped into the Earth's freshwater seas, the Great Lakes, was anybody's guess.
Now, much to our regret, we know all too well what the zebra mussel is and what it can do when it reproduces unchecked. And unless we are incredibly lucky, everyone will soon know just what a New Zealand mudsnail is, too, and what it can do to our lakes.
All because the Great Lakes shipping industry, the U.S. Coast Guard, the Interior Department, the U.S. Senate and a host of other agencies haven't done the job that American citizens expect of them.
The tiny mudsnails, which are native to New Zealand, have shown up in the Duluth-Superior Harbor and the St. Louis River estuary on Lake Superior near Duluth, Minn.
The snails were first found in North America in 1987 in the Snake River in Idaho and have invaded Rocky Mountain trout streams since then.
In some Western states, according to the Associated Press, the snails have displaced native insects, snails and other invertebrates that fish depend on for food.
Like zebra mussels, the problem with the mudsnail is that it has no natural predators in the Great Lakes that would keep its population in check. Mudsnails reproduce by cloning; one snail and its offspring can generate hundreds of thousands of clones each year, the AP reported.
They were spotted in Lake Ontario in 1991 and Thunder Bay, Ontario, in 2001.
Researchers told the AP that Lake Superior is too cold for them, but harbors and estuaries are just fine.
When the zebra mussel was first spotted in 1988, there was no real feeling of immediate peril. Lake St. Clair was far away, and upstream all the way. There was real shock and dismay, however, when the mussels were spotted in Grand Traverse Bay just three years later.
The mudsnail may not pose any real problem in the Great Lakes. The water may be too cold, a predator may come along to keep things in balance.
The better odds, perhaps, are that the snails will adapt and flourish and become yet another threat to Great Lakes fish.
Until someone gets serious about preventing ocean-going ships that enter the Great Lakes from dumping their ballast water here, we're in for plenty more mudsnails.
And sooner or later, some alien species introduced to the lakes will do real and lasting damage, and we'll be reduced to pointing fingers at each other and saying "I told you so."
Traverse City Record Eagle:
http://www.record-eagle.com/2006/may/02snail.htm>
Snail native to New Zealand found in Duluth-Superior harbor
DULUTH, Minn. (AP) -- A small, spiral-shaped snail that clones itself and is native to New Zealand has been discovered in Duluth-Superior Harbor and the St. Louis River estuary, raising concerns about the impact of another invasive species.
The snail, called the New Zealand mudsnail, is only about as large as a peppercorn when fully grown. But one snail and its offspring can generate hundreds of thousands of clones each year.
In some Western states, the mudsnail has displaced native insects, snails and other invertebrates that are important food for fish.
The mudsnails first were found in Idaho's Snake River in 1987 and have affected Rocky Mountain trout streams. They first were spotted in the Great Lakes in Lake Ontario in 1991.
More than 100 mudsnails were collected last fall in Duluth by Environmental Protection Agency researchers. The discovery, announced Monday, is the first finding of the tiny snail in Minnesota and Wisconsin waters.
Researchers suspect they were carried into the Great Lakes via ship ballast water.
"Our lakes, streams and rivers have enough stress on them, and they don't need something else like this," said Gary Montz, research scientist for the Minnesota Department of Natural Resources.
Researchers said Lake Superior is too cold for the mudsnail, but its harbors and estuaries are warm enough - like in Thunder Bay, Ontario, where it was discovered in 2001.
Like other invading species, the full impact of mudsnails may not be known for years.
A parasitic fluke controls mudsnail numbers in its native New Zealand, but the snail has no natural predators here.
Researchers are considering importing the fluke, but it may take years to determine if the flukes might cause their own problems here.
© 2006 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
