Barnacle Barnacle A barnacle is a type of arthropod constituting the infraclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmotile) suspension feeders, and have two nektonic (active swimming) larval stages. Around 1,220 barnacle species are currently known. The name "Cirripedia" is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Barnacles are encrusters, attaching themselves permanently to a hard substrate. The most common, "acorn barnacles" (Sessilia), are sessile, growing their shells directly onto the
Barnacle goose as they are led by the parents to wetland feeding areas. The barnacle goose is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds applies. According to Sveriges ornitologiska förening, the geese began breeding in Sweden in 1971, and according to Skansen, it was 40 years ago, more or less, when the entire population of barnacle geese left in the autumn to return in spring, soon after they began breeding in the wild. The number of barnacle geese is stable to increasing. The natural history of the barnacle goose was long surrounded with a