Diversity and occurrence of siphonophores in Irish coastal waters

摘要: Siphonophores are at times amongst the most abundant invertebrate zooplankton predators in oceans. Historically, siphonophores have been under-sampled and of studies conducted there has a bias towards oceanic oligotrophic waters where they considered to be more important. In temperate coastal regions, comparatively less is known about diversity abundance siphonophores, periodic blooms can restructure plankton communities correlated with high mortalities salmon aquaculture industry. To address this lack knowledge, samples were collected during two periods (March 2009-March 2011 April 2014-November 2015) from embayment southwest Ireland. total, three siphonophore species found, calycophoran Muggiaea atlantica, physonects, Nanomia bijuga Agalma elegans. atlantica was (250 colonies m−3), densities an order magnitude higher than either physonect. displayed distinct seasonality, whereas physonect sporadic occurrence. Comparing Bantry Bay Western English Channel (Plymouth Marine Laboratory's L4 station) indicates both regions share similar pattern inter-annual occurrence provides novel information on seasonality Irish waters.