Lionfish invading the Caribbean.

Lionfish in the Atlantic are termed invasive species: a non-native organism that has intruded into an area and may have serious detrimental effects on native organisms, the local economy and human health.

It is speculated that the root of the problem was only 6 lionfish accidentally released from an aquarium during hurricane Andrew in 1992. Genetic research supports this finger pointing but it is likely that many more have been intentionally released by “retired” aquarium enthusiasts. . Lionfish in their native waters reproduce once per year, but with the consistent warm temperatures of the Caribbean they reproduce monthly. Gelatinous egg masses, (each female can produce 2 million eggs a year) float to the surface and planktonic larvae drift for up to 40 days before settling, allowing for wide-range distribution by ocean winds and currents.

Slowly spreading throughout the greater Caribbean over the course of the years, the lionfish has now officially reached the Bay Islands on May 22nd 2009, a local dive shop reported the capture of an 8inch specimen in 21ft of water, inside the barrier reef about 200 m from shore, near Punta Gorda.

The cold water temperatures are keeping their numbers in check to the north, but this is not the case to the south where lionfish are taking over rapidly through the South Florida Estuaries, the Gulf of Mexico and the Caribbean Sea. Marine Scientists believe they will have established themselves as far south as Brazil within the next five to ten years.

Lionfish are suction feeders that consume their prey whole and are capable of eating creatures up to half their own body size, they are non-selective feeders, and with virtually no natural enemies in the tropical western Atlantic. Lionfish have been observed consuming 20 small fish in a 30-minute period and prey up to 2/3rd of their own length.

Samples of lionfish stomach contents in the western Atlantic have shown that they consume more than 50 different species, many of which are overfished and diminished to already critical levels.

They can inflict an extremely painful sting to humans, not usually deadly.

Due to the extent of the lionfish invasion, control is now the only option as attempts to eradicate existing lionfish populations would be impractical and probably unsuccessful.

In the Pacific groupers, sharks and coronetfishes are known to prey on lionfish. In the Atlantic, groupers are severely overfished and struggling to fill this role. The first documented case of grouper predation was in the Bahamas in 2008, when several groupers were captured containing partially digested lionfish remains in their stomach. For this, and many other reasons, predator populations need to be protected and allowed to recover.

Another method of control is something that humans are notoriously good at – let’s eat them! Apparently lionfish are tasty, with light, white and flakey meat, and have been received very well in some high end New York, Washington and Chicago restaurants following the success of Bermuda’s  Eat ‘Em to Beat ‘Em , campaign. Scientists from Roger Williams University, REEF, NOAA and the North Carolina Sea Grant (Morris et al, 2011) have just published a study detailing the nutritional benefits of lionfish consumption; lionfish have the highest concentration of omega-3 in their category, scoring above farmed tilapia, Bluefin tuna, red snapper and grouper. Claimed to be the “ultimate in guilt-free eating – delicious, nutritious and eco-conscious”. Lionfish is certainly in the ocean friendly seafood choice list.

To combat the invasion, the Roatan Marine Park  establish a program to control de population and report the sighting on their website. Working closely with the Department of Fisheries (DIGIPESCA) to issues licenses to spear Lionfish and estimate of 1000 are killed every month on Roatan by licensed hunters.

At the current rate of population growth, these measures are unlikely to be able to restore the ecosystem balance, but it is hoped it may perhaps slow the spread and buy a little more time for a solution.