Ecotourism impacts on reef fishes in a marine reserve during the COVID-19 era

Abstract

Marine reserves generally permit ecotourism within their boundaries as a source of income for local communities, but the impacts of ecotourism on wildlife are still poorly understood. The lockdown resulting from the COVID-19 pandemic in 2020 provided a unique opportunity to evaluate wildlife diversity in the absence of human activity. In a marine reserve in Mexico, we monitored fish assemblages before, during, and immediately after the lockdown to examine ecotourism impacts on fish assemblages. Our results show that fish density rose 2.5-fold during the lockdown, suggesting that ecotourism activities alter fish behavior. We suggest that the presence of divers and noise pollution generated by recreational vessels are important disturbance factors. In the absence of human activity, however, some fish may be more bold (hide less often) or may return to the reserve after having retreated to more tranquil (deepwater) areas. We hope that our findings spur efforts to improve the health of marine reserves through the establishment of effective management strategies to mitigate ecotourism impacts.