A comparison of the effectiveness of sea lamprey control in Georgian Bay and the North Channel of Lake Huron

Abstract

The sea lamprey control program in the Great Lakes has effectively reduced the abundance of sea lamprey, and, in conjunction with appropriate fishery management practices, has contributed to the restoration of valuable stocks of fish — particularly the salmonids. Sea lamprey producing tributaries of Lake Huron have been treated with lampricide on a continuing basis since 1966, and indications of decreasing abundance of sea lamprey have been evident since 1969. Control of sea lamprey has been more successful in Georgian Bay than in North Channel, as shown by the numbers of spawning phase animals captured in assessment devices, and by the incidence of lamprey-inflicted wounds on fish. The St. Marys River — the only know n uncontrolled sources of recruitment to parasitic sea lamprey populations of Lake Huron — is suspected of being the cause of the higher levels of sea lamprey abundance observed in the northwest pan of the lake.