Smallmouth Bass Population Characteristics and Movements in the Menominee River, Wisconsin-Michigan

Several segments of the Menominee River that borders the states of Wisconsin and Michigan support exceptional fisheries for smallmouth bass. Fishery managers would like to know more about the abundance, growth, mortality, and seasonal movements of these populations in order to make more informed management decisions. Specifically, there is some concern that smallmouth bass congregate in relatively small areas during fall and winter months, making them more susceptible to harvest compared to other portions of the open-water fishing season. Our primary objectives were to describe the population characteristics and seasonal movements of smallmouth bass in a portion of the Menominee River below Grand Rapids Dam to determine if current harvest regulations are sufficient to maintain the quality of this fishery. During 2014 and 2015, smallmouth bass were collected by electrofishing and were tagged with t-bar anchor tags and a dorsal spine was removed for age estimation. Sixty smallmouth bass ≥ 15 inches were implanted with acoustic receivers and their movements were monitored using both active tracking and fixed receivers. Preliminary results suggest smallmouth bass in the Upper Scott Flowage of the Menominee River make large seasonal movements within the flowage, have high size structure and low mortality.