Detroit River could become hotbed of sea lamprey activity

The Detroit River has the ingredients necessary to become a breeding ground for sea lampreys.

That's the finding of a recent study of the river by the Great Lakes Fishery Commission (GLFC), a joint Canada-United States organization that has been fighting the toothy, eel-like invasive species for decades.

While sea lamprey reduction efforts have been widely considered a success, a recent increase in the number found in Lake Erie has officials concerned.

"They're about three or four times higher than they should be," said Marc Gaden, communications director and legislative liaison for the GLFC. "We're doing well in our other lakes, but Lake Erie is kind of ground zero for lamprey abundance."

Streams connected to Lake Erie have been treated with lampricide, but Gaden said numbers in the lake are still too high. As a result, scientists have been studying connecting rivers and bodies of water in the hopes of finding where the lampreys come from.

While studying the Detroit River, crews determined that the river is a suitable habitat for lamprey, and that a small number are present — but mainly of the less destructive native variety.

"We ... think that because of the small number that they found, [the Detroit River] is a future threat as opposed to what's causing the problem in Lake Erie right now," Gaden said.

The GLFC believes that Lake St. Clair, specifically, the area near Walpole Island, contains the habitat producing the lamprey that eventually make it down to Lake Erie.

A collaboration with the Walpole Island First Nation has been established to pinpoint the exact breeding ground.