Quantitative differences in the fauna of boreal mud associations

Abstract

SUMMARYThe fauna of a muddy area in the northern North Sea (the Fladen ground) is compared with that of a similar area in a Scottish west-coast sea loch (Loch Nevis). These areas were selected because certain similarities in environmental features and in fauna, coupled with their marked difference in biomass, make them particularly suitable for studies of the factors affecting benthic production.For macrobenthos samples (from a grab) a coarse sieve with round holes of 1-3 mm diameter and a fine sieve with meshes of 0-5 mm side were used. Meiobenthos samples (from a corer) were sieved through a 0124 mm mesh and the total residue stained in rose bengal.The Fladen ground, depth 140 m, had annual bottom temperatures between 6-31 and 8-22 C and salinities between 35-20 and 35-2.50. The deposit was mainly of coarse silt with abundant tests of small Foraminifera. The fauna is redescribed. The characteristic species was the foraminifer Saccammina sphaerica. By separating empty tests from living specimens it is shown that this species was not so abundant as had been thought. The main lamellibranch was Thyasira equalis, not T. flexuosa as recorded in previous work. Other important species were the polychaetes Paraonis gracilis, Myriochele heeri, Spiophanes kroyeri, Tharyx sp., Lumbrineris impatiens, and Nephthys incisa. The standing crop of macrobenthos was 6-42 g/m2 wet weight.

5. Kinorhyncha (= Echinodera)

“…5.5.2 C) and anywhere under the coverslip. arctous Adrianov, 1999in Adrianov & Malakhov, 1999a Arctic Ocean: Russia: Nyholm 1947c;McIntyre 1961McIntyre , 1962McIntyre , 1964Bacescu & Bacescu 1956;Marinov 1964;Bacescu 1968;d'Hondt 1970;Sheremeteskij 1974;Sánchez et al 2012 Cephalorhyncha asiatica (Adrianov, 1989) Echinoderes asiaticus Adrianov, 1989: pp. arctous Adrianov, 1999in Adrianov & Malakhov, 1999a Arctic Ocean: Russia: Nyholm 1947c;McIntyre 1961McIntyre , 1962McIntyre , 1964Bacescu & Bacescu 1956;Marinov 1964;Bacescu 1968;d'Hondt 1970;Sheremeteskij 1974;Sánchez et al 2012 Cephalorhyncha asiatica (Adrianov, 1989) Echinoderes asiaticus Adrianov, 1989: pp.…”

Evidence for benthic body size miniaturization in the deep sea

“…The Fladen Ground site is located in the northern North Sea (58815'N 00845'E) and forms part of a £at muddy ground with a depth of about 150 m. The area has extensive oil industry activity and may be subjected to considerable ¢shing pressure (Jennings et al, 1999). The annual range of bottom temperatures in the Fladen Ground varies between 6 and 88C (McIntyre, 1961;Lee, 1980). The Faroe^Shetland Channel (FSC) site is located to the north-west of Shetland (61855'N 02848'W).…”

The distribution of some plankton animals in the English Channel and approaches: ii. Surveys with the Gulf iii high-speed sampler, 1958-60

“…The deeper water in this area is characterized by great temperature stability (cf. McIntyre, 1961) with a range of only one or two degrees around 7°C, and is thus a good deal colder than the subthermocline water of the Fastnet area which also acts as a reservoir of similar plankton. After the thermocline has been established in the northern North Sea in late spring and early summer, Sagitta elegans and associated cold-water forms begin to move south along the eastern side as they do in the Fastnet and Sole areas off the entrance to the English Channel.…”