The Problem with Lionfish

By Emma Duckworth

According to NOAA, over 80% of the ocean remains unexplored. This includes thousands of uncatalogued species that have yet to be discovered by scientists. However, scientists have encountered some of these species – but not where you might think. In the guts of invasive Lionfish populations, we may be able to answer some questions about what lies in the deep.

"Pterois antennata - Pez Leon - Lion Fish" by havivi2007 is licensed under CC BY-NC-SA 2.0.

Lionfish are fierce predators that are native to South Pacific and Indian Ocean coral reefs. Almost 40 years ago, Lionfish appeared far away from their native habitat – popping up across the Atlantic Ocean, off the Florida coast, and even down to the Caribbean. Researchers believe these populations resulted from domestic Lionfish that were released into the wild from aquariums. Due to their adaptive nature and ability to reproduce quickly, Lionfish populations exploded and quickly invaded new habitats.

With rapidly growing populations, Lionfish began to dominate deep reef food chains. They eat almost anything and have no natural predators keeping their populations in check, so they pose an incredible threat to coral reef ecosystems. Furthermore, Lionfish are hard to get rid of. The fishing industry for them is limited and they are nearly impossible to catch with nets. The alternative to net fishing would be spearfishing, which is neither efficient nor realistic since Lionfish inhabit reefs that are much deeper than spearfishermen can access.

So what's the big deal? Another invasive species that we seem to be stuck with but doesn’t have any super relevant effects in our everyday lives? That statement could not be further from the truth. Not only are Lionfish threatening coral reef ecosystems, but they are calling attention to a huge biodiversity problem; these fish are eating species that scientists haven’t discovered yet. We are losing biodiversity before we have begun to fully understand it! 

By monitoring deep reefs and studying predator-prey interactions of Lionfish, scientists discovered that Lionfish are preying on unfamiliar, uncataloged organisms. Luke Tornabene, an assistant professor at the University of Washington, was able to catalog a new species of deep-reef goby from watching Lionfish hunt. Researchers studying Lionfish have even found evidence in the stomach contents of Lionfish that indicate they are preying on species unknown to humans; scientists hope to catalog even more new species with this technique. 

For now, we can do our best to minimize the growth of Lionfish populations and do what we can to adapt and shift our research methods. This research is on the cutting edge of science and you can read more about these incredible efforts to catalog biodiversity of deep reefs here.