Negative impacts from non-native congener introductions have emerged as an immediate threat to black bass conservation and management. Largemouth bass (Micropterus salmoides) historically comprised the sole black bass fishery in Moss Lake, North Carolina. Alabama bass (Micropterus henshalli) were illegally introduced into Moss Lake and were first detected during a 2008 electrofishing survey conducted by North Carolina Wildlife Resources Commission biologists. Since this detection, Alabama bass rapidly increased in abundance throughout the reservoir, while largemouth bass abundance declined concomitantly and reached a low equilibrium, except within cove habitat of the upper reservoir. Alabama bass CPUE was generally 2–3 times higher than largemouth bass CPUE during the study, but Alabama bass were overall smaller in size and in poorer condition than largemouth bass. However, Alabama bass mean TL increased through time, corresponding to their expanding population. Alabama bass were smaller than large- mouth bass at ages 1–2; however, by age 3, growth rates of both species converged and became similar thereafter. Our findings improve understanding of black bass population characteristics changes following the introduction of Alabama bass on an existing native largemouth bass fishery. Fisheries agencies are encouraged to implement preventative and adaptive control measures to both discourage illegal fish translocations and coordinate unified practical management approaches to the ever-present threat of invasive species expansion
