There are nearly 660 fewer Indo-Pacific red lionfish in the waters of the Florida Keys National Marine Sanctuary, thanks to more than 40 teams of divers who participated in a series of ‘derbies’ aimed at reducing the population of this marine invader in sanctuary waters.

NOAA's Florida Keys National Marine Sanctuary, in partnership with Reef Environmental Education Foundation (REEF), hosted the inaugural series of lionfish derbies starting in September.

After receiving training on how to safely handle lionfish, whose venomous spines can deliver a nasty sting, divers were given one day to round up as many lionfish as possible. One team captured more than 100 lionfish. The largest lionfish caught measured over 12 inches in length and the smallest was less than two inches long.

REEF and sanctuary managers have been working with the Florida Keys dive community to remove invasive lionfish since early 2009. Scientists are concerned about the rapid population growth of lionfish in Keys waters and their lack of a natural predator in the Atlantic. Lionfish are known to feed on commercially and ecologically important fish species — including snapper, grouper and shrimp — and can disrupt the balance of the marine ecosystem.