BUFFALO, N.Y. (WIVB) — A crew from the U.S. Fish and Wildlife Service will be in western New York next month to assess the potential threat of sea lampreys.

The predatory, parasitic animal was described by the U.S. Fish and Wildlife Service as “a permanent, destructive element of the fishery” since they first invaded the Great Lakes a century ago.

They feed by attaching themselves to fish, rasping a hole with their suction-cup mouths before consuming blood and body fluids.

The U.S. Fish and Wildlife Service says that in the parasitic phase of its life, the average sea lamprey will kill up to 40 pounds of fish.

“Sea lamprey larvae hatch from eggs laid by adult lampreys in gravel nests, and drift into silty bottom areas where they burrow and live for several years,” The U.S. Fish and Wildlife Service said. “Also, larvae sometimes drift out of streams and settle in the immediate offshore areas near stream mouths.”

In order to stop them from reaching adulthood, surveys are conducted in hundreds of Great Lakes streams every year.

During these surveys, fishery biologists and technicians typically use electrofishing to cause the lampreys to reach the surface. But in deep waters, the U.S. Fish and Wildlife Service says a dissolving larvicide is used to send them up, where they can be collected.

Chemical control of sea lampreys was first initiated by the Great Lakes Fishery Commission in 1958.

“Since that time, the highly successful program has contributed significantly to the maintenance of the $7 billion Great Lakes sport and commercial fisheries,” the U.S. Fish and Wildlife Service said.

In 2003, Bayluscide, the larvicide that’s used, was determined to pose “no unreasonable risk to the general population and the environment when applied at concentrations necessary to detect larval sea lampreys,” the U.S. Fish and Wildlife Service said.

An assessment crew will be in the Niagara River from May 10-19 to find out how much of a threat sea lampreys could be to our local waters.