Are you one of those in the Panhandle who has not yet heard of the invasive lionfish? Well, now you have. This non-native member of the scorpionfish family was first seen in U.S. waters in 1989 off the coast near Ft. Lauderdale. Over the last two decades much has been learned about the biology and potential impacts of lionfish in our waters; read more at (http://myfwc.com/wildlifehabitats/nonnatives/marine-species/lionfish/) (https://blogs.ifas.ufl.edu/escambiaco/2012/08/17/the-invasion-of-the-lionfish/).
This past October the Florida Fish and Wildlife Conservation Commission held the first state lionfish summit in Cocoa Beach. Researchers, fishery managers, divers, commercial and recreational fishermen, and the general public were able to hear updates on research, discuss current issues, and provide input on future management needs with this fish. Here are a few of these notes.
What are the potential problems?
Though several theories on how they were released have been suggested, the data indicates they originated from 9 females that were part of the aquarium trade. Sixty-thousand lionfish continue to be imported into the state each year. Local densities are much higher locally; 400 fish/hectare in Florida compared to 80 fish/hectare in the Pacific. Pensacola studies show that the densities are higher on artificial reefs and since 2010 populations have doubled annually. They are larger in the Atlantic basin and may spawn 30,000 – 40,000 eggs every 2-4 days. Another potential problem reported are records of lionfish in the Loxahatchee and Indian Rivers; indicating that they are moving into brackish water.
What are the negative impacts?
Stomach analysis indicate 70 different species of reef fish are targets. Younger lionfish feed primarily on crustaceans and reef fish when they are older. Lobster fishermen in the Keys have found lionfish are the number one by-catch in lobster pots and have reduced their catch by 50%. Another study found on natural reefs they prefer blennies and on artificial reefs they are taking small snappers and sea bass, including groupers. Another interesting study compared reefs where the primary predator was a species of grouper, others where the predator were lionfish, and another set where both were present. On the reefs with grouper only there was a 36% decrease of juvenile fish. With lionfish the decrease was 94% and 114% when both predators were present.
So what can be done?
Several reports indicate that collecting tournaments are effective; Lad Akins of REEFS Inc. (www.reef.org ) reported a 69% reduction from one event in Key Largo. Another study had similar data but indicated that some spear fishermen were more successful than others, suggesting training may be needed to increase efficiency. Other reports indicate that work on conditioning native fish to consume lionfish have led these native predators to follow and even bite divers thinking that “free food” may be available; it was suggested that this idea not be pursued.
Locally lionfish rodeos sponsored by Emerald Coast Reef Association (www.ecreef.org) occur in Okaloosa County and Escambia County (http://www.myescambia.com/community/news/lionfish-round) did a pilot event this summer. Escambia will begin a full lionfish control program in 2014. If you have questions about the subject you can contact your local natural resource or Sea Grant Extension Agent.