The Manx Wildlife Trust, along with the Department of Environment, Food and Agriculture and an enthusiastic group of volunteers, recently carried out a survey for marine alien species on the Stone Piers in Ramsey. We were looking for 2 non-native species; Darwin’s barnacle and the Pacific oyster, as well as recording their native counterparts.
The survey covered the length of the pier, with different levels of abundance of each species at different points. Darwin’s barnacle ranged between ‘occasional’ and ‘common’, using a common biological survey scale, whereas the native barnacle was nearly always ‘abundant’. This showed that, even though the non-native species is already established, it is probably not causing problems for the native species. Indeed, it is at the same abundance level as the last survey, about 55 years ago! This was conducted shortly after its arrival in the early 1950s.
The survey found that the Pacific oyster became more common the further down the pier and it was also possible to count each one we found; 240 in total! Again, it is not thought that it is currently causing damage to the native species, but it is important to monitor changes in these species populations over time. These data will be the baseline for further surveys in future.
We are very grateful to the volunteers who joined us on the survey, which was the first in a series of events to celebrate the Ramsey Bay Marine Nature Reserve. If you would like to find out about future events like this, then join our mailing list by emailing Eleanor@manxwt.org.uk.
