Lionfish

This document serves as a reference for the controlling and management of the invasive Indo-Pacific lionfish (Pterois miles and P. volitans complex). Lionfish are expected in St. Eustatius waters in the near future and can have serious detrimental affects to the island’s marine environment, particularly to the populations of both ecologically and economically important fish species. Coral reef ecosystems can also experience degradation due to predatory stress caused by lionfish on coral reef grazers such as parrotfish (Scaridae).

The invasive lionfish also poses a threat to public health; the species has fourteen venomous spines over the length of its body which can inflict a painful sting. Particularly vulnerable to lionfish envenomations are those stakeholders of the Marine Park who have the potential of coming in close contact with the species such as fishers and divers. Recreational beach goers also face the potential of being envenomated. Envenomations can be particularly dangerous to infants, the elderly, individuals with a compromised immune system and those sensitive to the venom.

Due to the nature of the invasion of aquatic species in general and lionfish more specifically, it must be realized that a complete eradication of the species is impossible, therefore this plan will seek to actively manage lionfish in Statia territorial waters. The goals and objectives of this management plan are to adequately control the impact the species will have on the ecosystem level and with regards to the risk it poses to the community and to the local economy. Management goals and objectives are coordinated and communicated with different agencies to ensure local and regional cooperation, education of and outreach to stakeholders, research and management option development on the nature of the infestation, and a species control mechanism which will seek to limit the effects of species arrival.

Management actions should be clear in both the management of the species on a local level and contributing species information on a regional and international level. Management actions in this plan are divided into two stages; pre species arrival and post species arrival actions. Actions within the two stages can belong to phase one management actions, which are the first actions to be implemented, or phase two actions, which follow phase 1 actions and are continuous. Some management actions belong to both phase one and phase two management actions. The proposed management actions for the controlling of lionfish in the St. Eustatius National Marine Park include education and outreach on the nature and threats of the invasion, coordination with other agencies and organizations on management options, infestation research and development such as stomach content analysis and genetic sampling, planning and assessment in the form of lionfish action protocols and lionfish sweeps, and specimen control mechanisms such as species collection and eventual culling.

Appreciation is expressed to all those who assisted with technical support regarding this Response Plan, particularly the insight gained during the Lionfish Workshop hosted by the Bonaire National Marine Park in cooperation with the Reef Environmental Education Foundation and funded by the Dutch Caribbean Nature Alliance, and various workshops given by Chris Flook of the Bermuda Museum and Zoo. 

Lionfish, Pterois volitans and P. miles, are native to the Indo-Pacific and have recently invaded the Western Atlantic Ocean. Strategies for control of this invasion have included limited removal programs and promotion of lionfish consumption at both local and commercial scales. We demonstrate that lionfish meat contains higher levels of healthy n-3 fatty acids than some frequently consumed native marine fish species. Mean lionfish fillet yield was 30.5% of the total body wet weight, a value that is similar to that of some grouper and porgy species. A sensory evaluation indicated that lionfish meet the acceptability threshold of most consumers.

The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious impacts on coral reef food-webs. We have used an Ecopath-with-Ecosim model to predict the impacts of lionfish invasion on a coral reef community based on pre-invasion fish community data. Forty-six groups were defined, and an initial Ecopath model was balanced with a near-zero biomass of lionfish. In Ecosim, the near-zero biomass was eradicated by applying a very high fishing pressure in the first year of simulation. We subsequently (re-)introduced lionfish with a very low biomass, and allowed them to increase to very high abundance. With a near-zero lionfish biomass, the great majority of mesocarnivorous/omnivorous coral reef fish were predicted to be dominant while sharks were predicted to be the apex predators. Different management scenarios were established in the ecosystem to explore the eradication and resilience of lionfish. The management scenarios showed that if all adult lionfish were exploitable it will in theory be possible to fish the lionfish to a very low level, but the fishing pressure will have to be maintained, or the lionfish will recover. If the largest individuals are unexploitable it will be much more difficult to control the lionfish population