In March this year storm Emma hit Holyhead Marina, in North Wales, causing significant damage. Despite efforts to contain debris from the damaged marina, some debris drifted out of the harbour area into the marine environment. A consequence of this means there is potential for the carpet sea-squirt Didemnum vexillum (D. vex), a marine invasive non-native species, to spread to other areas.
The carpet sea-squirt us capable of forming large, flat colonies which reduce available habitat for other species. As well as growing over rock, pebbles, boulders, cobbles and gravel, the carpet sea-squirt can also commonly be found on man-made structures such as boats, docks, moorings, ropes, chains, plastic and shellfish aquaculture gear. More information can be found here.
Prior to Storm Emma the carpet sea-squirt was being contained within Holyhead marina after being fond on some of the floating pontoons and other artificial structures. These structures were damaged during the storm and have floated some distance – a floating pontoon was found 37km away and polystyrene washed up in Wicklow is believed to have come from the marina. So, there’s a chance we could find debris washing up on the Colourful Coast.
All sightings of possible debris in England should be reported to Natural England firstname.lastname@example.org. Where it is possible and safe to do so any debris found should be moved above the high tide line to prevent it from returning to the sea and help remove the risk of further spreading.
An advice note from Natural Resources Wales can be found below