Overview of Large Vessel Program
The Great Lakes are ecologically significant on a worldwide scale, as they contain 20 percent of the world's fresh water. Michigan, which includes 43 percent of the Great Lakes, has a considerable responsibility in the protection, management, and rehabilitation of this important fresh water resource. The mission of the DNR, Fisheries Division reflects our responsibilities as trustees for public resources, "to protect and enhance the public trust in populations and habitat of fishes and other forms of aquatic life, and promote optimum use of these resources for benefit of the people of Michigan".
To meet our public trust responsibilities, Fisheries Division funds and operates four research vessels to investigate, monitor and evaluate the status of aquatic habitats and fisheries resources of the Great Lakes. The four research vessels (RV) and survey vessels (SV) are:
- RV Tanner -- Lake Huron at Alpena
- SV Steelhead and the smaller RV Pimephales -- Lake Michigan at Charlevoix
- RV Lake Char -- Lake Superior at Marquette
- RV Channel Cat -- Lake St. Clair at Mount Clemens
These vessels are essential to fulfill the division's constitutional and statutory responsibilities as trustee for the preservation of public resources in Michigan waters of the Great Lakes. Work performed by these vessels includes evaluations of fish population abundance levels, survival, age structure, growth, behavioral patterns, movements, reproductive ecology, as well as diet for fish stocks providing important resources for the people of Michigan. As the Great Lakes are some of the world's largest freshwater systems, work conducted on MDNR vessels often involves collaboration with other state, federal, and tribal agencies. In particular, forage biomass estimates for Lake Michigan are made in cooperation with U.S. Geological Survey, as well as other agencies.
The vessels contribute to the process of evaluating stocking practices to determine optimal strains, densities, sizes, times and techniques to maximize survival and return to creel while minimizing cost. Vessels collect fish which are used for contaminant analysis to assess the potential risk to public health from consumption of fish from the Great Lakes. Data collected by the vessels are used to evaluate population level effects of habitat alterations on fish communities. Data are also used to develop and test models that predict the effects of regulation changes, predict the influence of aquatic exotic species on fish communities, as well as determine sustainable harvest levels and partition the allowable catch among sport, commercial, and tribal fisheries. International multijurisdictional management plans that include fish community level objectives for major fish stocks depend heavily on data provided from our research vessels as well as other research vessels (Great Lakes Association of Science Ships).