An Unabated Nuisance: The Ecological Disaster of the Lionfish Invasion in the Atlantic
By Anna Milena Jurca, Staff Contributor
Lionfish are an invasive species that threaten to become one of the worst ecological predators in the Atlantic. Over the past thirty years, this exotic species has spread from the coast of Florida through the rest of the Gulf of Mexico and the Caribbean. Without natural predators and international cooperation to address the spread of this invasive species, lionfish prey on reefs and displace native fish populations in American and international waters. Despite recent attempts to manage the problem, lionfish are an aquatic nuisance likely to stay.
The federal government has defined invasive species as non-native species that have adverse economic, ecological, and/or environmental effects on native habitats or human health. One of the most significant adverse impacts of invasive species includes displacing native species that are adapted to and necessary for the local native ecosystem. Invasive species can prey on local species, carry exotic diseases, interfere with the reproduction of local species, and harm humans. Costs to the U.S. are estimated in the range of tens of billions of dollars.
“Lionfish are vicious predators that can eradicate over seventy percent of a native reef.”
Lionfish are native to the Indo-Pacific region and first arrived to waters off the coast of Florida in the mid-1980s, most likely through illegal aquarium dumps. DNA analysis has traced back all lionfish in in the Atlantic to about six to eight female lionfish released off the coasts of Florida. For years, sightings of the beautiful fish have been rare, but in recent years, lionfish have spread north to Connecticut and south to the Bahamas, Cuba, Jamaica, Dominican Republic, Costa Rica, Honduras, and Columbia. Lionfish are vicious predators that can eradicate over seventy percent of a native reef. In 2005, Oregon State University conducted a controlled experiment in which lionfish displaced seventy-nine percent of the native fish population within just five weeks. They prey on young fish, which lionfish swallow whole. Local fish do not recognize them as predators and do not swim away.
As evidence of their predatory success, a biopsy of a lionfish from North Carolina revealed large amounts of interstitial fat. James Morris, the pre-eminent scientist from National Oceanic and Atmospheric Administration (NOAA) studying the invasion of lionfish into U.S. coastal waters, said lionfish are not just overweight – they are so obese that they show signs of liver damage. Moreover, a female lionfish can reproduce after just one year (compared to three to five years for native species) and produces about forty thousand eggs every three or four days. While the grouper occupies the same ecological niche as the lionfish and would be a natural competitor, it has been overfished in the Atlantic. Fearing no natural predators or competition for resources, feasting on a buffet of local fish, and outpacing reproduction of other species, lionfish have recently become an unabated aquatic nuisance.
The U.S. government has responded to the ecological disaster, but is lacking an effective approach. Executive Order 13112 established the National Invasive Species Council, which monitors invasive species, develops guidance, sets up an information sharing system, coordinates action of thirteen federal agencies, and provides recommendations for international cooperation. As well, Title 16 of the U.S. Code gives the National Park Service authority to manage invasive species in national parks. Last year, NOAA issued guidelines to control the lionfish invasion by promoting the fish for human consumption and encouraging divers to kill it. Several affected countries have already adopted regulations that allow the taking of lionfish in “no-take” zones, or marine protected areas, which are protected nursing grounds from which fish otherwise cannot be taken. The Department of Interior issued a “Lionfish Response Plan” in an attempt to set guidelines for management. A few weeks ago, the Fish and Wildlife Service held the first Lionfish Summit in Cocoa Beach, FL to address the issue. However, because the lionfish invasion is so dramatic and well established, and therefore unlikely to be controlled because of the rapid reproduction, federal agencies are hesitant to allocate more resources to the problem.
” … it is questionable how successful any attempts to abate the nuisance would be, considering the very small number of fish released in the first place.”
Environmental litigation has not yet drawn significant attention to the issue. Citizen suits under the Endangered Species Act – stemming from the lionfish’s threat to listed endangered species – could potentially bring more federal attention to the problem and speed up formulation of more effective regulations. Environmental organizations have successfully sued the Environmental Protection Agency over the regulation of other aquatic nuisances, including the introduction of the zebra mussel in the Great Lakes through ballast water in ships. However, no actions have been filed regarding the dramatic spread of lionfish and international cooperation with other affected states is underdeveloped. In addition, it is questionable how successful any attempts to abate the nuisance would be considering the very small number of fish released in the first place.
Current programs in the U.S. focus on education, awareness, and ecosystem management, which are some of the reasons the problem arose in the first place. They may be effective to raise awareness and prevent future introductions of invasive species, but they are unlikely to effectively remediate this one.