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Location: Essexville, MI./Saginaw Bay. | A big fish caught off Sarnia turns out not to be the nasty foreign invader many feared.
But there's a downside -- it was a grass carp, a cousin of the fish it was mistaken for.
And just like that other behemoth, the grass carp is a destructive species that doesn't belong in the Great Lakes.
The lowdown on the one-metre fish caught in a fishing net this past Wednesday by Milford Purdy was confirmed yesterday by Ontario's Ministry of Natural Resources.
"It's not a big concern, other than the fact that it's an invasive species and it's likely been introduced by humans," said Barry Radford, a ministry spokesperson.
The grass carp is flagged on the MNR's website as a harmful exotic species.
In the lower Mississippi River, grass, big head and silver carp -- cousins in the same Asian carp family -- have devastated the ecosystem and many fisheries.
The big fish feeds on water plants, which stirs up river and lake bottoms and clouds the water.
Native to east Asia but now found all over Europe and the U.S., the grass carp is the largest species in the family. They can live more than 15 years, weigh more than 50 kilograms and grow longer than one metre.
The fish caught last week was at first thought to be either a big head or silver carp, both highly destructive because they feed on more of the nutrients that would supply the bottom of the aquatic food chain.
Authorities have braced for the arrival in the Great Lakes of the most destructive of the Asian carp, with a $US9-million underwater electric barrier set up in the Chicago canal, a potential entry point from the U.S. into the lakes.
While the fish landed this week may not be as fearsome as first thought, its presence was yet another reminder of the threat posed by exotic species to those who make their living from the lakes.
"I don't like that they have found another one there," said Peter Meisenheimer, executive director of the Ontario Commercial Fisheries' Association.
According to the resources ministry, the first grass carp was caught in Lake Erie in 1985. Between 1989 and 1998, three more were captured in southern Lake Huron. And in 2003, a grass carp was caught at the mouth of the Don River in Lake Ontario.
The captures were called isolated. And the ministry doesn't believe an established population of grass carp is in the Great Lakes.
The incidents likely stem from people importing live Asian carp for food, or farmers putting them in ponds to clean up unwanted vegetation, says the MNR.
But Meisenheimer isn't buying those explanations.
"It's always been assumed they aren't being reproduced in the Great Lakes, but the more often these things show up, the more suspicious you are they are showing up because they're established," he said.
Edited by walleye express 7/31/2007 5:40 AM
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