Invasions of exotic species

Lake Erie most vulnerable to future invasions of exotic species: report

TRAVERSE CITY, Mich. — A U.S. report says dozens of foreign species could spread across the Great Lakes in coming years and cause significant damage to the environment and economy, despite policies designed to keep them out.

The National Center for Environmental Assessment issued the warning in a study released this week.

At least 185 are known to have a presence in the Great Lakes, although the report says just 13 have done extensive harm to the aquatic environment and the regional economy.

Perhaps the most notorious are the fish-killing sea lamprey and the zebra mussel, which has clogged intake pipes of power plants, industrial facilities and public water systems, forcing them to spend hundreds of millions on cleanup and repairs.

The report suggests that Lake Erie — shallowest of the lakes — and the shallower portions of the other lakes were most vulnerable to invasions.

Shallow areas tend to be warmer and have a greater variety of life than deeper water, said Mike Slimak, an associate director of the national centre.