An alien invasion is under way on the beaches of south Co Wexford. In Bannow Bay, a Japanese seaweed has established a firm foothold, according to Coastwatch.
Volunteer surveyors found that the seaweed, Sargassum muticum, which is native to Japanese waters, has been "spreading rapidly" over a 3km stretch of the bay's tidal channels - aided by abnormally warm water following the recent heatwave.
Local TD John Browne, Minister of State for the Marine, likened its spread to earlier accidental introductions of alien invasive species that led to trouble for native species, such as the grey squirrel out-competing our native red squirrel.
The search for the latest alien invader was carried out by more than 60 members of St Kearn's Rowing Club over the past 10 weeks. They covered every channel of Bannow Bay, which is a protected area for the range of its habitats and wild birds.
Coastwatch said the boating community needed to become aware of the seaweed so boats were less likely to carry fronds of it to other areas.
"This is important as the rowing club is thriving and participating in regattas right around the country."
Work in a trial area for removing the seaweed will proceed later this month, after necessary permits are obtained.
Evidence of plants adapting to sea-level rise as a result of climate change was also found.
Rare perennial glasswort that used to grow on bare mud in the bay appears to have moved to higher ground, nestling between saltmarsh grasses and flowers.
"Findings were deemed so significant that an immediate summary report is being prepared to consider implications for the bay and for coastal zone management and biodiversity in Ireland," Karin Dubsky, co-ordinator of Coastwatch, said.
