MSU researchers working on a natural repellent for sea lamprey control
Blocking certain streams with lampricides will cause sea lamprey to avoid waterways and effectively eliminate concentrated populations of sea lampreys.
At the recent Michigan Fish Producers Association Annual Conference in Traverse City, Michigan Sea Grant Extension conducted a daylong educational workshop that included a look at the use of repellant for sea lamprey control. Jason Bals, of the Department of Fisheries and Wildlife at Michigan State University (MSU), made a presentation on this topic and efforts to control one of the most destructive invasive species in the Great Lakes. Jason is working with Dr. Michael Wagner, lead researcher and assistant professor of Fisheries and Wildlife at MSU, in completing a large-scale field test of repellents for blocking spawning migration of the invasive sea lamprey.
Each year, millions of dollars are spent trying to keep sea lamprey populations in check, with new control methods investigated that would enhance cost effective in control efforts. Sea lampreys still continue to cause mortality in certain fishes that are of economic importance to the commercial and recreational fisheries in the Great Lakes.
Adult sea lampreys run up streams to spawn and then die. After the eggs hatch and develop into the larval state, they can live in the streams for up to four to six years, at which time, they do not feed on fish. This is the time that they are vulnerable to chemical treatment using lampricides, and these treatments are very expensive.
Unlike salmon, though, adult sea lampreys do not return to the same stream where they were born. They are guided by the smell of other sea lampreys that reside in these streams. Adult sea lampreys choose spawning grounds based on the success of larvae inhabiting the stream. Conversely, the smells of dead or injured lampreys repel adult lampreys as it signals a poor place to spawn. Sea lampreys have a strong sense of smell and existing research has focused on using pheromones to attract sea lampreys into traps. There are many scents in the streams where sea lampreys spawn and using pheromones, alone, to attract sea lampreys might not be fully effective.
Wagner and collaborators have concentrated sea lamprey repellents in the lab and have used the repellents to block, successfully, sea lamprey migrations in experimental streams. During 2013, Wagner will be working on the first large-scale field test of sea lamprey repellants by attempting to block an entire watershed from sea lampreys during their spawning run. Focusing on blocking certain streams with these chemical repellents will result in sea lamprey avoiding environmentally sensitive areas and diverting them into waterways where lampricides could be used more effectively to eliminate a more concentrated population of sea lampreys. This allows sea lamprey control agencies to be more cost effective by using less lampricides.
This project is funded by an Environmental Protection Agency grant in collaboration with the Great Lakes Fishery Commission, U.S. Fish and Wildlife Service, and U.S. Geological Survey. For more information on this project, contact Mike Wagner at 517-353-5485.