岩手県船越半島沖に集積した瓦礫における底生生物の分布 土田 真二・藤原 義弘＊＊・高橋 幸愛・ソーントン ブレア† 河戸 勝・屋良由美子・山北 剛久・藤倉 克則・北里 洋

Abstract

Five marine debris aggregations were found at a depth of 540m off the Funakoshi Peninsula, Iwate, during a dive of the ROV Hyper-Dolphin on October7th 2013. These debris aggregations were entangled with each other and were placed patchily on the bottom at the upper mouth of a deep-sea canyon. Many animals such as sponges, cnidarians, ophiuroids, comatulids, asteroids, and fish were observed on the debris that was composed of cans, plastics, wood, fishing gear, and others. Population density was highest on wood and fishing gear（240inds. m－2）, followed by cans, and was lowest on plastics（66．5inds. m－2. Population density on natural substrata such as outcrops was 141．8inds. m－2, which was lower than those of wood and fishing gear. The compositions of animals on these debris were predominated ophiuroids（100％ on cans and plastics, 97％ on wood and fishing gear）. The population densities of ophiuroids on the debris were much higher than those 5m and 10m away from the debris on the sediment. These results indicated that marine debris could harbor many more animals than natural outcrops and sediment in the deep sea.

More information

Identifiers

Catalogue record

Export record