Evaluating harvest incentives for suppressing a socially-valued, but ecologically-detrimental, invasive fish predator

Abstract

The legacy of intentional freshwater fish introductions across the western United States has fostered social tensions over the control of nonnative species in some contexts. Overcoming tensions and implementing effective control programs is important for mitigating impacts to native species. We modeled the efficacy of incentivized harvest for controlling nuisance smallmouth bass (Micropterus dolomieu) using empirical responses measured during fishing tournaments on two reservoirs that are sources of nonnative predators to critical habitat of native species. Simulations demonstrated that anglers could suppress adult smallmouth bass by 90%–99% in under 30 years, but were contingent on program participation and density dependence in harvest efficiency (i.e., catchability) and population demographics. Catchability differed between systems and varied temporally within the same system, thereby suggesting tournament structure could be adapted to increase harvest rates. Incentivized harvest should not be dismissed as a viable control strategy alone or in tandem with other methods in small lentic systems.