Examining the Impacts of Climate Change and Potential Policies on Invasive Lionfish

Abstract

Lionfish, Pterois volitans and Pterois miles, are invasive species of fish from the Indo-Pacific that were introduced in Florida waters in the 1980s and have since spread into the Caribbean and along the Southeastern Coast of the United States.. Without any natural predators, lionfish present a danger to marine ecosystems in the Atlantic—overconsumption of herbivorous fish leads to unchecked algal overgrowth in coral reefs and collapse of higher trophic levels. We investigate how climate change, particularly ocean warming and the shoreward migration of the Gulf Stream, will affect the possible spread of invasive lionfish north along the U.S. East Coast and potentially into the Chesapeake Bay. Applying MAXENT ecological niche modeling (ENM) and a custom Lagrangian adjustment algorithm to account for changing boundary currents, we projected habitat suitability from 2020-2090 under the SSP5-8.5 high-emissions climate scenario. Identifying sea temperature and salinity as the primary predictors of lionfish presence, we conclude that lionfish are likely to establish perennial populations as far north as North Carolina and possibly to the coast of Virginia by 2090. While they are unlikely to establish a permanent population within the comparatively shallow Chesapeake Bay, adjacent offshore and coastal waters will experience a significant increase in habitat suitability. These predictions establish a timeline that motivates proactive policy initiatives to control lionfish and mitigate damages in Mid-Atlantic waters. We extensively review current aquatic invasive species policies from eight states along the East Coast to determine existing aquatic invasive species policies in comparison to the state’s specific lionfish policies, or lack thereof. Our results show commonalities among state policies, such as prohibiting the release of invasive species alive, focusing on population control or eradication, and officially labeling species as invasive to secure management resources. We then created a policy application to act as a guide to show how a state’s current aquatic invasive species policies can be used to assist in lionfish-specific policy creation and implementation. Our results expand the understanding of invasive species distributions in the face of climate change, ensuring our ecological niche modeling results inform proactive, research-based policy decisions for future aquatic species invasions.