November 19th 2011
Biodiversity Corner - Alien Invasions

Allena A. Joseph
Department of Fisheries
Pictures courtesy Bahamas DMR, Stuart Cove Dive

Colorful tropical fish are fun to watch in an aquarium or a home fish tank. But what happens when exotic fish are released into the wild? Most often these fish survive and start taking over the sea. One such example is the Lionfish- an invasive alien species that may soon threaten our St Lucian waters as it comes down to our seas in ocean currents.

The Lionfish, known scientifically as Pterois volitans, is hard to miss with its red and white stripes and long venomous spines. This fish is native to the tropical Indian and Pacific region from Japan to Australia. Officials and scientists believe that the lionfish was introduced into the Atlantic Ocean in 1992 after escaping from an aquarium in Florida in the wake of Hurricane Andrew. Since then the Lionfish have made our Caribbean waters their home and confirmed sightings have been on the rise since 2004.

The Lionfish travelled to the Bahamas over ten years ago, but it was not until 2004 that reports of the sightings were confirmed. The number of Lionfish sighted has increased significantly as the population spreads across the Caribbean region. Lionfish have been observed all over the Bahamian archipelago, including the Turks and Caicos Islands. These alien fish have found their way to as far south as Bonaire where the first confirmed report was on October 26th 2009. Since then, approximately 60 lionfish sightings have been reported in Bonaire. Also, increasing numbers of lionfish have been sighted in neighbouring Dominica, St. Kitts Nevis, Antigua and more recently Martinique!

Lionfish are a threat to our already stressed marine ecosystem. They have a BIG appetite and feed on all the fish found on our coral reefs. Lionfish are able to grow and reproduce faster than native species like our snapper or pot fish. There are few fish that can eat the Lionfish; therefore their population keeps growing much faster than that of other fish. Because of this, they can pose a serious threat to native fish, their habitat, coral reefs and overall ecosystem function. They feed on many of our important fish species. They eat young snapper, grunt and grouper species, leaving none behind to reproduce to support the fishery that is important for food here in Saint Lucia.

Lionfish are also harmful to humans with its venomous spines and pose a threat to sea bathers, divers and fishers. The lionfish spines release a venomous sting that is fatal to its prey and can be very painful and dangerous to humans. A lionfish sting is very unpleasant and can make a person quite sick. Its painful sting can cause a wide range of symptoms from bellyache and swelling to chest pain and seizures. If you or someone you know is stung by a lionfish there are steps you can take to reduce the effects of the sting.

Once the Lionfish invades the marine environment they are here to stay. There is no way to completely get rid of them from our waters. However, every Saint Lucian can play a part to help control this invasion by staying informed and following proper guidelines. Together we can protect our fisheries from the harmful effects of the lionfish. Let us all do our part! And be prepared for the invasion.

One could say that it was just a matter of time till the invasive Pacific Lionfish was spotted in St. Lucia's waters. It was spotted at the Honeymoon Reef by a visitor on a dive with Sandals Dive Centre at the end of October and an official response on this serious Fisheries matter has been made by the Fisheries Department.

If you spot a lionfish do not touch it. Report ALL Lionfish sightings to the Department of Fisheries at telephone number (758) 468-4140/43 or the Marine Police at (758) 456- 3870 or the Soufriere Marine Management Association at (758) 459- 5500.

Discuss Story