Study finds way to cut sea lamprey numbers

Minnesota scientists say they've found a way to reduce sea lamprey populations in the Great Lakes by attracting them to areas where they can be sterilized.

Lampreys are eel-like, blood-sucking creatures that have devastated Great Lakes fish populations for decades. But scientists at the University of Minnesota have discovered a chemical sex attractant that draws adult lampreys to spawning streams, where the males can be caught and sterilized, the St. Paul (Minn.) Pioneer Press reported Monday.

"This presents the possibility of a whole new environmentally safe tool for controlling sea lamprey in the Great Lakes,'' said Peter Sorensen, a university professor of fisheries, wildlife and conservation biology who led the study with chemistry professor Thomas Hoye.

Experts say the discovery, detailed in the November issue of Nature Chemical Biology, might also help control other problem species, such as carp.

Sea lampreys invaded the Great Lakes during the 1920s and 1930s, depleting such native fish as lake trout and whitefish. In Lake Huron, lampreys are blamed for reducing the lake's trout catch from 3.4 million pounds in 1937 to nothing by 1947.

Copyright 2005 by United Press International