Association between the catches of round gobies and smallmouth bass on the upper Niagara River

We wanted to confirm the presence of round gobies (Neogobius melanostomus) in the upper Niagara River and determine if there was a negative association between the catches of round gobies and smallmouth bass (Micropterus dolomieu). Our approach was to compare the catch rates of round gobies and smallmouth bass by anglers based on their method of fishing (from boat or from shore) and the fish they sought (anything or black bass). During 2003, both boat anglers and shore anglers caught round gobies in the upper Niagara River. The catch rates of round gobies and smallmouth bass for shore anglers who sought anything were positively and significantly correlated (r = 0.081, P < 0.001). The catch rates of round gobies and smallmouth bass for shore anglers who sought black bass were negatively and significantly correlated (r = 0.141, P < 0.005). Correlations were not done using the catch rates of round gobies and smallmouth bass by boat anglers because they caught so few round gobies. Our results suggest that round gobies did not disrupt fishing for smallmouth bass on the upper Niagara River during 2003 if disruption is defined exclusively by the association between catch rates of smallmouth bass and round gobies. However, catching round gobies did lead to angler perceptions of poor fishing quality.