The LionFish Invasion

Hola! Bonjour! Hi :D. This week we look at one of the most voracious invasive species to affect the marine environment, the lionfish 
(Scientific name: Pterois volitans). 

The Red Lionfish.©Bent Christensen

Distribution

Map showing the worldwide distribution of the lionfish.©U.S. Geological Survey

The red lionfish is native to the indo-pacific region but has found its way into unwanted waters such as the Atlantic, closer to North America (spotted in 2002), the Gulf of Mexico, the Caribbean Sea, spotted in countries such as: Cuba (2007), Jamaica (2008) and Trinidad and Tobago (2010). The lionfish is regarded as one of the most beautiful additions to any household aquarium. Scientists speculate that the dumping of the lionfish into waterways via the aquarium trade is one of the main modes of introduction of this species into non-native areas. 


What makes this particular IAS so successful?

The red lionfish camouflaging in its natural habitat (the coral reef) using its
striped color.  ©The University of Wisconsin

As an IAS in new territory, the local organisms don't stand a chance against these predators. Due to its striped color and presence of multiple venomous dorsal spines, local organisms know to stay away. The fact that this species has no known predators in these new areas, coupled with the idea that there are no evolutionary predator-prey relationships developed (Saunders, 2015) to keep the ecosystem in check, the red lionfish can multiply rapidly without hindrance.  

Impact

The ferocious lionfish has the ability to severely impact coral reef ecosystems negatively. By disrupting the stability of the ecosystem and rapidly declining local fish populations, this directly impacts the fishery and tourism sectors of countries highly dependent on this resource. Hixon et al (2009) observed that this IAS has the ability to reduce juvenile fish populations up to 79% within a span of 5 weeks! The video below shows how the lionfish feeds and why it is capable of such devastation!

Methods of Mitigation

Lionfish being spearfished in Florida. ©National Geographic

Experts have agreed that this problem cannot possibly be eradicated, therefore population management should be of utmost importance (Spencer, 2013). One strategy currently being used by countries such as Florida and Trinidad and Tobago, is the commercialization of the lionfish by promoting spearfishing of the IAS. However, by reviewing history, environmentalist have taken a chapter out of the green mussel story and have again appealed to the over exploitative nature of humanity, by adding this apex predator to the local cuisine! By encouraging chefs and restaurants to use these organisms in their menu, these countries hope to gain money while solving a huge problem. 

Lionfish cuisine being promoted in a restaurant. ©Erin Spencer