Density, biomass and community structure of demersal fishes off the Pacific coast of northeastern Japan

Abstract

Demersal fish communities were studied on the lower continental shelf and the upper continental slope along the Pacific coast of northeastern Japan. Species composition, number and weight of each species were examined based on otter trawl samples at 45 stations. Mean density and biomass of demersal fishes were 131 ha -1 and 21 kg ha -1 , respectively. The ten most abundant species comprised of about 95% of total number and weight of overall catch indicating simple species composition. Gadiform fishes Theragra chalcogramma, Gadus macrocephalus and Physiculus maximowiczi were the most important species by number, weight and frequency of occurrences, and three main community types represented by the three key species were recognized. Theragra-dominant community showed higher density and biomass, and lower diversity than Physiculus-dominant community did. Species diversity of demersal fish community was negatively correlated to density and biomass. Density and biomass of demersal fish community were high on the uppermost slope, and the high abundance resulted from low-diversity communities dominated by T. chalcogramma and G. macrocephalus.

Depth-gradient structure of the demersal fish community on the continental shelf and upper slope off Sendai Bay, Japan

“…5 ) . The species composition was, however, should take temporal persistence into account, persistent at several sites, particularly in the interalthough until now most studles on the zonation of mediate-depth waters (ca 240 to 370 m) between the demersal fishes did not consider temporal variation shallower and deeper sites where the persistence was (e.g Fujita et al 1993). The trawl catches off Sendai relatively low (Fig 6).…”

“…'Present address: National Science Museum, Tokyo, Hyakunin-cho 3-23-1, Shinjuku, Tokyo 169, Japan Demersal fishes on the continental shelf and upper slope off Sendai Bay, Japan, have been surveyed since 1988 by the Tohoku National Fisheries Research Institute, Hachinohe, to investigate fisheries resources in the area. Using a part of the data, Fujita et al (1993) classified 3 community types represented by each of 3 numerically dominant gadiform fish species, Tl1erag1-a chalcogramn~a, Gadus macrocephalus and Physiculus maximowiczi. The shelf community was dominated by P. maximowiczi, while the uppermost slope community, in which the biomass of the demersal fish community was very high, was dominated by T. chalcogramma and G. macrocephalus .…”

Annotated checklist of the sharks, batoids and chimaeras (Chondrichthyes: Elasmobranchii, Holocephali) from waters of Russia and adjacent areas

“…6 (type locality: Misaki, Japan) Common names: En -Whitefin dogfish; Ru -Beloperaya sobach'ya akula; Jp -Kasumi-zamé; CzSvětloun Ritterův Distribution: Northwestern Pacific. Pacific coasts of Hokkaido and Honshu islands, Japan Amaoka et al, 1989;Nakaya and Shirai, 1992;Fujita et al, 1993;Shinohara et al, 2009). Russian area: it was known only one specimen from near Pacific side of the southern Kuril Islands (Fedorov and Parin, 1998;) and probably northern Kuril Islands .…”

“…1 (type locality: Misaki, Japan) Common names: En -Blackbelly lanternshark; Ru -Svetyashchayasya chernobryukhaya akula; JpFuji-kujira; Cz -Světloun svítivý Distribution: Currently the range of this species is limited to Northwestern Pacific (Ebert and Schaaf-DaSilva, 2009;Ebert et al 2011). The closest occurrence from Russian waters is Hokkaido Island and northern Honshu Island, Japan Nakaya and Shirai, 1992;Fujita et al, 1993;Shinohara et al, 2009). Marine species.…”

Environmental Variability Affects Distributions of Coastal Fish Species (Maryland)

“…The deck sampling, identification, and catch-recording procedures followed Fujita, Inada, and Ishito (1993) and Sparre and Venema (1998). For catches less than 30 kg within a haul, the sample was weighed, labeled, and stored in cabin at -20℃.…”