LAKE STURGEON MONITORING PROJECT
The St. Louis River, once a historical location of a large, self-sustainingName`Ogimaa giigonh (lake sturgeon) population, is in the initial stages of re-developing a naturally reproducing population. Lake sturgeon are a long-lived species capable of reaching very large sizes, yet this same life history makes them vulnerable. Sexual maturity is not reached until 15-20 years of age and spawning by individual fish often only occurs every other year. Lake sturgeon were likely eliminated from the river by the early 1900’s due to the combined effects of exploitation, water pollution, habitat alteration, and logging practices. Following water quality improvements in the late 1970’s – early 1980’s, the Wisconsin and Minnesota Natural Resources Departments began the long process of a large-scale sturgeon reintroduction program in 1983. Stocking of both fry and fingerling sturgeon occurred from 1983-1993 and again from 1998-2001. Survival of the stocked sturgeon has been fairly high and it is anticipated that sturgeon will soon be spawning in the St. Louis River again.
While initial results from the stocking program are encouraging, there is still a large gap in knowledge of lake sturgeon life history and in particular, habitats required by juvenile lake sturgeon. In 2005, the Resource Management Division, with funding support from the U.S. Fish and Wildlife Service’s Tribal Wildlife Grant program acquired by the Grand Portage Band, initiated a juvenile lake sturgeon monitoring project on the St. Louis River. The project involved capturing and radio-tagging 10-25 sturgeon annually from 2005-2007. Once tagged, the fish have been located using telemetry gear with a goal of identifying the crucial habitats needed by this life stage of sturgeon. Fall 2008 will mark the end of this portion of the project, at which point we will begin looking at the data that has been collected over the past four years. Our next step in the process will be to map the bottom habitat and substrate in areas where the tagged fish have been located using telemetry gear. This information will be made available to fishery managers charged with rehabilitating and protecting lake sturgeon around the Great Lakes.