The U.S. Fish and Wildlife Service assisted two Canadian agencies this July with sea-lamprey tracking in the Great Lakes. Canada’s Department of Fisheries and Oceans, the University of Guelph, Ontario, and the Service used acoustic-telemetry to track sea-lamprey behavior in the St. Marys River-Lake Huron area. The project is part of the Service’s Sea Lamprey Management Program, which aims to control populations of sea lampreys, an invasive, parasitic fish species, in tributaries of the Great Lakes.

Scientists from the Service and Canada worked together to track sea lamprey behavior in the St. Marys River-Lake Huron area. Project scientists examined lamprey migration up to and around assessment traps downstream of the U.S. Army Corps of Engineers’ powerhouses in the St. Marys River.

Scientists placed hydrophones, or underwater microphones, in the channel downstream from the powerhouses to track lamprey movements once they entered the channel.  They also implanted radio tags into several sea lampreys to determine the depth at which they were moving. To monitor fine-scale movements at the assessment traps, project scientists also implanted several hundred lampreys with passive integrated transponder tags, and visual identification tags. PIT technology enables scientists to inject machine-readable tags into fish. By placing PIT-tag antennas around a trap at the downstream powerhouse, the team was able to monitor when lampreys entered the trap, how they behaved once inside and if they escaped. To support the information from the PIT-tag technology, scientists also mounted an underwater camera on the trap. The Sea Lamprey Management Program plans to use the results to enhance the effectiveness of alternative control methods, such as trapping and barriers.

Sea lamprey is a jawless, parasitic fish species that spread throughout the Great Lakes in the 1930s, threatening native fish populations. Today, it continues to threaten native and popular game fish. The Sea Lamprey Management Program protects the fishery and related economic activities in the basin, bringing annual benefits to the region of $4 to $6 billion a year. The Service delivers its program of integrated sea lamprey control in the U.S. waters of the Great Lakes as a contract agent of the Great Lakes Fishery Commission. 

For more information, contact Jessica Barber, USFWS, at (906) 226-1241.