Introduction of the European common barnacle Balanus perforatus Brugiere (Crustacea, Cirripedia) into Korean waters

초록

The common barnacle Balanus perforatus Brugiére, 1789, (Crustacea, Cirripedia) from the European waters is recently discovered to be established very quickly in the eastern coasts of Korea. It has jumped a historic oceanographical barrier from the European waters to the Northwest Pacific waters. It is a warm water species between 36° N and 52° N, occurring commonly in the Mediterranean and along the eastern Atlantic coast from north Wales to West Africa. Usually, it occurs in the lower half of the littoral zone and may extend into the sublittoral on rocks and artificial structures and is sometimes common in wave exposed situations but also present on ships' hulls. Balanus perforatus was found for the first time in Guryongpo (35°59'10"N, 129°33'20"E ), Yangpo (35°52'40"N, 129°31'30"E), and Gampo (35°43'18"N, 129°30'27"E) Ports on June 24, 2006. Two years later in 2008, 31 sites were visited in all around the South Korean coasts. This survey showed that 13 sites were invaded by this species and they were concentrated rather in the east coasts where some of the important international shipping traffic ports are located such as Busan and Ulsan. Therefore, it is possible to assume that the observed invasion pattern may suggest ships’ hull fouling and/or their ballast water as pathways and dispersal after establishment according to the circulation pattern of Tsushima Warm Current in this region. Based on the northern limit of its distribution in Sacheon Port (37°50'00"N, 128°52'36"E) in 2008, this would be approximately equivalent to movement of water with passive larvae of about 300 km to the north for two years. As a conclusion, the rapid colonization of this introduced species extending its distribution north by 150 km a year should be monitored together with the impact of this invasion on the other species or communities in Korean coasts.