Vertical distribution of zooplankton over the northern slope of the Wyville Thomson Ridge

• Published in: Journal of Plankton Research
• Main Authors: Pipe, R.K., Coombs, S.H.
• Format: Text
• Language: English
• Published: Oxford University Press 1980
• Subjects: Articles; Norwegian Sea; Wyville Thomson Ridge; Wyville-Thomson Ridge; Calanus finmarchicus; North Atlantic
• Online Access: http://plankt.oxfordjournals.org/cgi/content/short/2/3/223; https://doi.org/10.1093/plankt/2.3.223

A single oblique plankton haul, comprising discrete, depth-stratified samples, was taken over the northern slope of the Wyville Thomson Ridge. Water temperatures taken concurrently showed a Layer of relatively warm North Atlantic Oceanic water, at 8.7°C at the surface and 8.4°C at 400 m, overlying Norwegian Sea Deep water, the temperature of which fell to 0°C at the bottom of the haul (580 m). The species have been classified according to vertical distribution into five groups which were taken, predominantly: (a) below 530 m (b) between 430 m and 510 m (c) throughout the entire depth range sampled (d) in the upper 400 m and (e) in the most superficial 60 m. These groupings are discussed in relation to the temperature profile and examples of the vertical distribution of individual species are described. Of the 59 taxa of zooplankton taken on the haul, the most abundant was Calanus finmarchicus which accounted for 54.7% of total biomass. Both biomass and the number of species were greatest below the temperature discontinuity in Norwegian Sea Deep water.