Bathyal demersal fishes of Charlie-Gibbs Fracture Zone region (49-54°N) of the Mid-Atlantic Ridge: Ⅱ. Baited camera lander observations

摘要

Demersal fishes appearing at baited cameras at 2500 m depth either side of the axis of the Northern Mid-Atlantic Ridge (MAR) at 54°N and 49°, north and south of the Charlie Gibbs fracture Zone respectively, showed significant differences in species composition between north and south. A total of 19 taxa were observed, with Hydrolagus affinis, Bathyraja richardsoni, Halosauropsis macrochir, Histobranchus bathybius, Synaphobranchus kaupii, Coryphaenoides armatus, Corphaenoides brevibarbis, Coryphaenoides mediterraneus/leptolepis, Antimora rostrata and Spectrunculus crassa occurring at all locations. The total species assemblage comprised 40% of species captured by trawl at the same locations indicating a high proportion of scavenging species on the MAR. The most abundant was C. armatus showing shorter arrival times and larger body size in the north, suggestive of higher population density and higher food availability. The next most abundant species A. rostrata however showed faster arrival in the south but larger size in the North. No differences could be discerned between stations at the same latitude east and west of MAR axis.