Homebodies or Roamers? Genetic Assignment of Lake Sturgeon in Lake Superior

Lake sturgeon (Acipenser fulvescens) spawn in rivers of the Great Lakes and generally return to the lakes after spawning.  A very small portion of their life is spent spawning; however, the bulk of the research has focused on this important life event.  Little is known about sturgeon movement and ecology during the rest of their life, when they are not spawning.  Genetic data from spawning populations allow for the assignment of non-spawning lake sturgeon to their population of origin to detect movement patterns.  Juvenile and adult lake sturgeon captured throughout Lake Superior were analyzed using 12 microsatellite loci.  Potential effects of stocking were also assessed by detecting the movements of stocked lake sturgeon from the Wolf/Fox River in Lake Michigan.  In general, both juvenile and adult sturgeon tend to stay close to their spawning site.  However, there was evidence of long distance migrations and certain areas (e.g., Keewenaw Bay) appeared to attract migrants.  Stocked sturgeon appeared to have strayed from the stocking site and one individual was identified in a spawning run north of the stocking site.  Genetic data from spawning populations have proven to be a useful tool for understanding lake sturgeon movement patterns.