ISSN:1064-1262    

DOI:10.1080/10641269309388547

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Bays and semi‐enclosed seas provide a natural spatial scale at which to characterize the trophic organization of marine communities. This article summarizes the information available on the trophic organization (species number, relative abundance, seasonal abundance, foraging style, and diet) of the marine bird community at the spatial scale of the entire Bering Sea. This required synthesizing work in English (pertaining to the east) and Russian (pertaining to the west), much of it published after 1980. A total of 51 seabird species (not counting loons, grebes, and seaducks) regularly inhabit the Bering Sea. Based on work available (to 1990), the minimum number of breeding seabirds in the western Bering Sea is 3–1 × 106along the Asian coast (Cape Kamchatskiy to the Bering Strait), 106in the Commander Islands, 1.1 × 107in the Aleutian Islands, and 1.2 × 107along the North American coast (Uriimak Pass to the Bering Strait). Nonbreeding seabirds include 3 species of albatross, 3 pagophilic gulls, and on the order of 3–3 × 107Pufftnusshearwaters. Seasonal movements are primarily meridional (north‐south) and strongly tied to the breeding cycle. Major foraging styles include surface gleaning (as in fulmars), bottom gleaning (as in cormorants), and mid‐water pursuit (as in murres). Major prey resources include euphausiids, squid, immature fish (notably Walleye pollock), and copepods. The data show that less than five avian species account for most of the energy flux to the avian community. The data indicate that this flux is strongly seasonal and highly localized in space. Localized seasonal concentrations of invertebrates (notably euphausiids and copepods) appear to be more important sources of energy flux to birds in this ecosystem than at lower latitudes.

ISSN:1064-1262    

DOI:10.1080/10641269309388548

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Beginning in the 1920s, Homer Smith and co‐workers described kidney functions in marine fish. He also described fluid loss via the kidney (diuresis) associated with scale loss, which usually killed fish in 24 h or less. Pacific salmon also experienced diuresis following stress, but only for an hour or two, and rarely died. Marine juvenile salmonids died following loss of >30% of their scales. Death followed a period of increasing lethargy, decreased circulatory output, and decreased weight and length. At death, the fish were limp (flaccid paralysis) and rigor mortis was delayed. Immersion of descaled fish in freshwater or dilute seawater or infusion of physiological saline had little effect.

ISSN:1064-1262    

DOI:10.1080/10641269309388549

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor