I’ve posted previously about the lionfish invasion that is threatening coral reef and other marine ecosystems throughout the Caribbean, Gulf of Mexico, and Southern Atlantic Seaboard of the United States. As I noted in earlier posts, it is the general consensus of the scientific and conservation community that eradication of lionfish from the Atlantic is impossible. There have been some anecdotal reports that native predators such as groupers and snapper are beginning to recognize lionfish as prey, but there is no systematic evidence, as of yet, of widespread predation. So the conclusion remains that human intervention is the only way to keep lionfish populations in check. The good news is that there is growing evidence that systematic removal efforts can indeed be effective in controlling lionfish populations and in reversing their negative impact on reef health. A study published earlier this year found that populations of snapper and grouper rebound by 50-70 percent once lionfish are removed. And it isn’t necessary to remove 100 percent of lionfish for recovery of native fish populations to take place; the study found that reduction of lionfish populations by as little as 75 percent will do the trick. This is important, given difficulties in reaching lionfish at depths beyond the limits of divers.  Also, removal efforts may become more difficult over time, as lionfish on reefs where regular culling takes place begin to wise up and hide from divers (click here for a cute poetic rendition of findings of a study on this behavioral adaptation).

Thus the challenge is to find a sustainable basis on which to undertake the systematic removals that are needed to keep lionfish populations under control. Continue reading →