Hawaii Invasive Species Council

Unomia stolonifera

Photo credit above: DLNR

DESCRIPTION:

• “Unomia stolonifera, (formerly Xenia sp.) commonly known as the “stoloniferous fire coral”, is a fast-growing soft coral that originates from the Indo-Pacific region. It is known for its ability to reproduce quickly and outcompete native corals, ultimately smothering and displacing them.” (ICRI)
• “Unomia stolonifera forms very soft colonies up to 9 cm high and 6 cm wide. The soft coral is characterized by its white-pink coloring and is known for its dance-like movements in the ocean currents.” (reeflex.net)
• “The polyp body is up to 25 mm long, the tentacles are up to 10 mm long and bear leaflets arranged in three rows, with 20-25 leaflets in the outermost row and a gap of up to one leaflet width between adjacent leaflets.” (reeflex.net)
• This species spreads through fragments which can be spread by boats and floating objects. Once re-attached it can grow on almost anything. (CNRH)

IMPACTS:

• Kills off native corals by smothering growth behavior.
• Death of reef from smothering leads to drastic decrease in fish stocks. 
• The species has a strong rotten fish smell, and when widespread the smell will begin to spread to fish living in the area. (Washington Post)
• Coral smell and appearance has negative affect on tourism, by decimating fish stocks, killing coral, and due to its unpleasant smell and feel. 
• In Venezuela, the invasive coral has spread to over an 1000 square foot radius, where all of the impacts above have made an enormous impact on coastal livelihoods, lifestyles and the economy.
• Fisherman in Venezuela report that last year was one of their worst catches on record. Israel Sosa, a longtime fisherman in these waters, says his haul has dropped from about 33,000 pounds of Albacore fish in a 48-hour shift just a few years ago to closer to 220 pounds. (Washington Post)

ERADICATION & CONTROL METHODS:,

• Hand removal can be a slow-going, but successful way to remove this species. Caution must be taken not to spread fragments, which can re-establish themselves and colonize new areas.
• Tarping can be used to slow the spread of the coral.
• Tarps, sandbags and bleach can be used to starve the corals of oxygen, which jumpstarts decomposition. (SAME)
• A novel technique to dispose of the coral has been being used in Venezuela. An ultrasound gun is used to cut through the coral, which is then sucked up by a machine and disposed of. (Washington Post)

WHAT YOU CAN DO:

• Properly dispose of aquatic plants when you can no longer keep them. (Seal aquatic plants in plastic bags and dispose in the trash.)
• Comply with to signs to not fish in areas where recreation is restricted due to Unomia presence. 
• Report any Unomia seen in new areas to Division of Aquatic Resources.
• Never dump species into the ocean, rivers or natural bodies of water. Contact local aquarium shops for assistance with rehoming.