LIONFISH DISASTER LOOMING
By Dave Harter, Beaufort County

Contrary to my normal practice, I am writing again this week about the invasion of Pacific lionfish into our coastal waters off of South Carolina.  One reason is that I want to make sure that this subject is taken more seriously than the introduction of a new fish recipe, and the other is that I have received some recent marine ecology study reports with some very disturbing conclusions.  Maybe it is because I have been such a big supporter and contributor to our artificial reef system for the last 20 years and bottom fishing for grouper and red snapper have dominated my offshore excursions but I believe this invasion could be the most significant manmade/natural disaster that our fishing community and our artificial and coral reefs have ever faced.  The speed at which their populations seem to be progressing appears to be geometrical in rate and, I fear, way too fast for the glacial pace and strapped budgets of our ecosystem and fisheries managers.  

A September 2008 paper from the Department of Zoology at Oregon State University detailed a study of how the “Invasive Indo-Pacific lionfish reduce recruitment of Atlantic coral-reef fishes”.  Based on the timeline of when the lionfish were first seen in our Atlantic coastal waters and their genetic signatures they surmised that the fish were probably accidentally released from aquaria during hurricane Andrew in 1982.  Given Florida residents’ penchant for releasing non indigenous critters when they tire of them this could be a kind assumption and just a part of the beginning of the end.  Regardless, the lionfish are also taking over coral reefs in Bermuda, the Bahamas, Puerto Rico, Jamaica, off the Yucatan Peninsula and our own coastal waters as far north as Rhode Island.  Essentially this study in the Bahamas by Oregon State University zoologists was to see what kind and how much of our reef fish were the lionfish consuming.  The results are shocking:

Lionfish caused reduction in the recruitment of native fishes by an average of 79% over 5 weeks.
Lionfish herd and corner their prey and use a fast strike attack which is a novel strategy to our local fish.
Lionfish have few documented predators.  This is in part due to their poisonous spines and that our bigger, over fished predators such as sharks and grouper are not used to eating them.
Of 38 species of reef fish studied, the lionfish were eating at least 23 of them in addition to crustaceans like juvenile spiny lobster.  One fish was observed eating 20 wrasses in 30 minutes.
Lionfish were observed eating prey up to 2/3 of their own size.
They feed throughout the day and behaved as if they expected no competition.
They are eating fish which control the seaweeds from smothering the corals.
Over fishing, pollution and climate change will aggravate the problem. 

I am used to scientists being conservative and limited in their conclusions and that makes the following two quotes from this one year old study scare me into an even greater sense of urgency.

“The documented reduction in net recruitment due to lionfish predation is an important component, but likely represents an underestimation of the effects of lionfish on native reef-fish communities.”

“The current geographic extent and rapid population growth of lionfish in the Atlantic makes complete eradication untenable.  Nonetheless, it would be prudent for affected nations to initiate targeted lionfish control efforts as soon as possible.”

A report I had last week from some divers at a wreck site about 45 miles offshore of Hilton Head indicated a lionfish population of about 500 on one structure.  There were a few barracuda, some large grouper and not much else.

I’m not sure what to tell my readers what they can do but our first line of defense,  SC Department of Natural Resources, is working on an action plan.  We should know soon what that will be.

Dave Harter of Hilton Head is a leading salt water conservationist and outdoor writer from Hilton Head.  He is a board member of SC Wildlife Federation.