Fish Passage Through Three Types of Structures in Diked Coastal Lake Erie Wetlands

AbstractOver 40% of Great Lakes fishes are wetland dependent, and more than 70% benefit from wetlands periodically. As such, restoration and rehabilitation of Great Lakes coastal wetlands have increased dramatically. This necessitates a balance among varied management objectives, including fish passage. The presence of water control structures commonly found on diked wetlands can limit fish passage if not open all the time. We sampled three diked Lake Erie coastal wetlands to assess how different structures affected fish passage. Water control structures included a pool-and-weir fish ladder, swing gates, and an open culvert. Fyke nets were set five to seven times at each site between April and October 2015. One net was set outside of the wetland, a short distance away from the passage structure, and the other was set inside the wetland, with the net wings enclosing the opening of the structure. Catches were compared for catch rate, three measures of community similarity, and the wetland fish index (WFI). ...