Cooperative Fish and Wildlife Research Units Program: Wisconsin Fishery
Education, Research and Technical Assistance for Managing Our Natural Resources

The West Branch of the Wolf River (WBWR) running downstream through the Menominee Reservation from the Bass Lakes to the mill pond in Neopit, Wisconsin, supports a naturally-reproducing population of native brook trout. The sustainability of this population is important because little is known regarding the movements of brook trout within this system and these movements could have important implications for brook trout management. In general, it is unknown whether brook trout utilize the entire river or if they generally remain within a single river segment. Additionally, within-river movements of brook trout may have increased following recent removal of two dams on the WBWR. Brook trout may also leave the river on a seasonal basis and enter the Bass Lake system, which provides deeper water and may represent important overwinter habitat. However, the Bass Lakes support several potential brook trout predators (e.g., northern pike, black bass) and non-native competitors (e.g., rainbow trout, kokanee salmon). The proportion of brook trout that enter the Bass Lake system and return to the WBWR is not known at this time. Brook trout can also leave the lower WBWR and enter the mill pond at Neopit. A rapids located upstream of the mill pond likely prevents upstream return of these fish to the WBWR, but the number of fish entering the pond is unknown. Consequently, both the Bass Lake system and the Neopit Mill Pond could act as sinks for the WBWR brook trout population. The objectives of our research are to determine if: 1) brook trout in the WBWR utilize multiple river segments during the year; 2) if a large percentage of brook trout enter the Bass Lakes and Neopit Mill Pond and 3) if most brook trout entering the Bass Lakes and Neopit Mill Pond do not return to the WBWR.