The barnacle is a crustacean that causes great trouble when it gets stuck on boat bottoms.

The warning applies to the entire Baltic coast, from Skåne up to Gävleborg.

- The barnacle warning has been around for 20 years and warns of when barnacles get stuck on boat bottoms in specific geographical areas.

The warning makes it easier for boat owners who want to do the right thing for the environment and avoid painting the boat bottom with biocide paint, says Carl Rönnow, expert in environmental and sustainability at the Swedish Boating Union, in a press release.