Status of Cisco in Western Lake Superior

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Cisco are an important native fish species in Lake Superior that moves energy and nutrients across habitats both vertically and horizontally, serve as forage for top-level predators, and support large-scale commercial fisheries. Unfortunately, cisco recruitment, indexed by annual lake-wide bottom trawl surveys, has been sporadic with few strong year-classes produced in recent years. Down-looking hydroacoustic methods have been developed and implemented recently to estimate cisco spawning biomass, but a major weakness in the use of this technology is the inability to effectively sample the surface waters where high numbers of cisco have been collected in trawls fished just below the surface. Even more recently, up-looking hydroacoustic methods have been developed and this project will implement this new technology to determine the degree that traditional down-looking hydroacoustic surveys underestimate cisco spawning biomass. In addition, this project will contribute to a comprehensive, multi-agency cisco status survey of the western end of Lake Superior. This is a notice of intent to award a single source cooperative agreement to University of Minnesota - Duluth under justification 505DM 2.14.B 4. Competition for the award is not practical as the University of Minnesota - Duluth, has an expert professor in hydroacoustic data collection, population modeling, and Lake Superior fisheries, is uniquely qualified to lead and supervise this project. The Service, through the Ashland Fish and Wildlife Conservation Office will be substantially involved in this project by assisting with development and refinement of specific research objectives, providing technical assistance with the data collection, statistical analyses, and editing of manuscripts, ensuring project highlights are shared with the scientific community and other interested parties both orally and in writing, and by serving as an active member of a University of Minnesota - Duluth graduate student advisory committee.

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