It blights the beaches on Jersey's south coast for months on end during the summer, but now a local teenager has found an ingenious way to use sea lettuce, that might well win him an international prize. Charlie Cadin, who is 18, has made a surfboard out of the green stuff.
He has entered a competition run by surf company Vissla and non-profit SurfRider Foundation, which is highlighting the ways surfboards can be made out of upcycled or sustainable materials. Student, Charlie shapes surfboards in his spare time, using recycled materials. You can watch him create his board here:
You can see the other entries here. Voting closed at 6:59am on Friday.
Winners will be announced on 28 October.