A long seaweed (typically 1-3 m long) with wiry stems that have small, oval-shaped blades (up to 2 cm long, sometimes toothed), with small spherical gas bladders (up to 3 mm in diameter) attached to them. The stems are thin and cylindrical, with many branches radiating from them in a spiral pattern. When the seaweed is stretched out horizontally, its branches hang straight down. Small tubular projections may be present during the reproductive period.
Japanese Wireweed grows on hard surfaces in intertidal and shallow subtidal areas. It has the potential to compete with native seaweeds, including ecologically important kelp and eelgrass. It can also be a nuisance, fouling organisms, attaching to aquaculture equipment, fishing nets, boats, etc.
Japanese Wireweed is a known invasive species in Europe and on the West Coast of North America. It was recently found in Halifax Harbour, and it may be present in other areas of Nova Scotia.
Thin, wiry, cylindrical stem with branches in a spiral pattern. Small blades (up to 2 cm in length, sometimes toothed). Small gas bladders (diameter up to 3 mm) attached to branches.
Japanese Wireweed was first discovered on the West Coast of North America in 1944. It was found in White Rock and Buccaneer Bay, British Columbia.
Ensure any watercraft, fishing gear, etc., is clean and free of debris and unwanted organisms before relocating to another area or body of water. Report any sightings to DFO. If possible, include a photo and/or collect and freeze a specimen.