Trapping and a sterile-male release techniques are alternative technologies to lampricide treatments that are being used to control sea lampreys in the St. Marys River.  These techniques have been employed in the river since 1991, and  were intensified in 1997.  Traps operated by the Service and its partner, the Department of Fisheries and Oceans, Canada, removed over 8,000 sea lampreys (45 percent of the spawning population) from the river which borders the U.S. and Canada. 

In addition to removing the reproductive potential of females, traps also removed males which reduced competition for sterile males seeking mates in the river.  About 33,000 male sea lampreys captured in 17 Great Lakes tributaries in the U.S. and Canada were sterilized and released into the St. Marys River.  The sterile-male-release technique reduces reproduction by causing females to waste their eggs in matings that will fail. 

The combination of trapping and sterile-male release reduced reproduction by about 90 percent during 2005.  The technique has reduced reproduction in the river by about e86 percent since 1997. 

The U.S. Fish and Wildlife Service delivers an integrated program of sea lamprey management in U.S. waters of the Great Lakes as contracted agent of the Great Lakes Fishery Commission.

For more info contact Michael Twohey at 906-226-1226.