Florida's Marine Invaders

| Don't Release Your Pets  | Green Mussels | Pacific Acorn Barnacles | Lionfish | Other Marine Invaders | Useful Web Sites | Terrestrial Invasives


Invasive species: A species of plant or animal that is not native to an area and that has a harmful effect on the environment or on native species.


Don't Release Your Pet

Many non-native animals and some aquatic plants that are becoming a nuisance in Florida were introduced into our environment as pets or aquarium plants that either escaped or were released into natural areas.For resources related to pet releases, please click here.


Green Mussels

Green MusselsThe Asian green mussel, Perna viridis, is closely related to the New Zealand green mussel which is imported to the US as a food item.  Asian green mussels are thought to have been introduced to Florida through shipping activities (in the ballast tank of ships).  They were first reported in Tampa Bay in 1999; by 2002 they had spread to NE Florida and SE Georgia.  In June, 2004, hundreds of green mussels were found growing on boulders on both the north and south sides of the St. Augustine Inlet.  By 2007, the mussels had spread as far north as South Carolina and south into the Indian River Lagoon.  A second mussel, the Charrua mussel, Mytella charruana, has been found in Jacksonville, FL and Savannah, GA in large numbers. To read more about green mussels, click here.


Pacific (pink) acorn barnacles

Large pink acorn barnacles, native to the eastern Pacific Ocean have begun to appear along the Atlantic coast of Florida, primarily on boats in the St Augustine area.  Click here for an article about these barnacles, which are a potential fouling and environmental hazard.

pink barnaclepink barnaclepink barnacle



A study released in 2004 revealed the presence of 16 different species of Pacific Ocean fish on reefs in the western Atlantic Ocean.  These fish are thought to have been released into the Atlantic by aquarium owners, as all 16 species are common to the saltwater aquarium trade.  The most abundant fish in the group is the lionfish. 

lionfishLionfish have been reported from waters off Florida's coast since at least the 1980's.  They are now established throughout western portions of the North Atlantic Ocean. Since about 2005, lionfish spread rapidly through the Caribbean and into the Gulf of Mexico. Their northern range expansion seems to be limited by temperature--established populations are found as far north as North Carolina and Bermuda. Occasional lionfish are reported from New England, but they are not believed to survive the winter months in that region. Lionfish have been spotted off the Bahamas at a depth of 1000 feet.

Listen to Maia McGuire speaking about lionfish on NPR's Science Friday (Nov 11, 2016) at this link.

Aquarium owners are reminded to NEVER release plants and animals that have been purchased at a pet store into the environment.  These plants and animals are likely not native to the area.  If they survive, they may begin to take over from native plants and animals, sometimes replacing native species.  One example of this is hydrilla, which used to be a popular freshwater aquarium plant.  The state of Florida now spends about $20 million every year trying to control this plant in freshwater lakes and ponds.


Other Marine Invaders

Florida's subtropical climate makes it an ideal home for many tropical and temperate plants and animals.  Every day, thousands of people pass through the state, by road, rail, boat or airplane.  These factors combine to make Florida a high-risk area for invasive plants and animals.  Recreational boaters can contribute to the spread of many marine non-native species if they transport them on their boat hulls from one location to another.  The link below is for a slide presentation about marine invaders in Florida--to view the slide show, simply click on the link.  To download the presentation, left click on the link and select "save target as."  This presentation was created for middle and high school ages.


Other Useful Websites


Terrestrial Invasives

  • Chinese tallow or Popcorn tree (226KB PDF)
    Photos of popcorn tree removal at the St. Johns County Agricultural Center (10/21/04)
  • Invasive plant race game
    Download these three files to have the materials needed to play the invasive plant race game.  This game, developed by Maia McGuire, teaches ways that invasive plants are introduced, and ways that they can be controlled.
  • "Too many to count" activity (2.3MB PDF)
    Download this to have the materials needed to use this activity, which simulates the use of quadrats for sampling a plant population.  The activity can include the introduction of an invasive plant, which takes over the area over time.
  • Alter-Natives Brochure
  • Revised in 2013, this document from the Ixia Chapter of the Native Plant Society provides suggestions of other plants that could be used to replace invasive plants in the landscape.