The upper St. Lawrence River is widely known for its world-class Great Lakes strain muskellunge (Esox masquinongy) fishery. This population has been proactively managed through the efforts of an International St. Lawrence River Muskellunge Working Group that led to the development of a muskellunge management plan that has evolved over three decades. The goal for management remains: “To perpetuate the muskellunge as a viable, self sustaining component of the fish community in the St. Lawrence River, and to provide a quality trophy fishery”. The process has served as an effective model for regional conservation of an apex top predator that has both a single-species and a more holistic community perspective.

Project Title: Long-term research, management and monitoring for conservation of native muskellunge

As a directive of the management plan, long-term monitoring of muskellunge has been ongoing since 1990 and recent population changes have been detected using this important data series. In the past decade, sampling has adapted to incorporate a community perspective and with additional data series involving wetlands, habitat, and lower trophic levels and water chemistry, is approaching a more holistic view of muskellunge. Beginning in 2005 widespread mortality of adult muskellunge was observed and attributed to the invasive viral hemorrhagic septicemia virus VHSv. Since the mortality events in adult muskellunge, significant declines have been observed in adult catch rates in the spring spawning survey and abundance of young. In light of these trends, heightened management concerns exist relative to future population recruitment, potential for continued adult mortality, and future population vitality.

These recent trends and the management plan highlight the need for continued monitoring and directed studies of population dynamics and ecology. Population monitoring is crucial to understand future trends in the muskellunge population in response to the mortality events. Maintenance of critical habitats is imperative to ensure sustained natural muskellunge reproduction. A great deal of progress has been made in these areas in previous work, including studies of spawning ecology and nursery habitat requirements. The information obtained in these studies will be used to develop a more comprehensive understanding of habitat and population dynamics, and will be put to use in guiding enhancement strategies to improve muskellunge recruitment.

Location: St. Lawrence River, Thousand Islands Region

Timeline: 1983-present

Field participants:
Staff of the SUNY-ESF Thousand Islands Biological Station

Principal Investigator:
John M. Farrell

Federal Aid in Sportfish Restoration Grant F-61-R & National
Fish and Wildlife Foundation Special Projects Grant – USFWS – Fish Enhancement Mitigation and Research Fund

John M. Farrell, SUNY-ESF
Syracuse, NY 13210 USA, 315/470-6990