Summer Movement of Burbot (Lota lota) in an Isolated Michigan River and Pre-Restoration Assessment of the Grand River Fish Assemblage in Downtown Grand Rapids, Michigan, USA

This thesis research consisted of two complimentary projects. The first focused on understanding the ecology and life-history of an isolated population of a freshwater fish, the Burbot; the second on a pre-restoration assessment of the fish community in the Grand River. Understanding life-history strategies of species is important to recognize changes in behavior caused by anthropogenic effects. Burbot (Lota lota), are important apex predators in their native range, is understudied, and exhibits complex life-history strategies. Specifically, little research has been done on isolated river populations. My research objective was to assess Burbot movement and habitat use over a one-year period. 17 Burbot the Rogue River, MI, were radio tagged and tracked for the summer to classify habitat use and establish home-range estimates, allowing for more focused management of riverine Burbot populations. Burbot moved infrequently during summer months and utilized underwater structures, which adds to the understanding of Burbot ecology and behavior. Many rivers have been channelized and/or dammed, altering flow regimes, habitat availability, sedimentation rates, and aquatic organism passage. The Grand River in downtown Grand Rapids, Michigan has experienced these effects with five run-of-river dams, all constructed at the turn of the 20th century. Since 1974, a fish ladder has been present on the largest of these dams, but most native fish species still struggle with upstream passage. A restoration project is underway to remove these dams and reconstruct the historic rapids. Evaluating the effects of river restoration require preliminary data on lotic community structure and function. Results of a multi-year survey to examine the fish assemblage of downtown Grand Rapids to assess pre-restoration conditions. I documented a diverse fish assemblage with a fish taxa richness of over 50 species (pooled across four years), including the state threatened River 5 Redhorse (Moxostoma carinatum) and Logperch (Percina caprodes), the obligatory host of the federally endangered Snuffbox Mussel (Epioblasma triquetra). These pre-restoration observations suggest that the fish assemblage is diverse and species-rich, and sets the stage to evaluate the fish community during and after the restoration project