Morning of 13th November: Continuing our shells collection cruise, our next site, a little further south on the Faroes Bank, came up with another surprise: hundreds of live collected specimens of Glycymeris glycymeris. We know this species (which can live up to 200 years) from St Kilda, the west coats of Scotland and points south, but we weren’t expecting to find it this far west in the north Atlantic and as far as I know it has not been found elsewhere in the Faroes.
Shortly afterwards, the weather began to turn, and in the light of predicted bad weather around the Faroes, we decided to head across to our other main area of interest, where we were planning to collect shells for Tamara. This was Viking Bank in the northern North Sea/Norwegian Sea. Tamara and Rob planned a full 80 potential stations in three separate areas. Winds reached force 8 on the journey across to Viking Bank, and we were thankful for the relative stability of GO Sars. At a session of presentations in the ship’s seminar room, we got a bit of detail about the very promising progress with the ARAMACC projects.
However, when we resumed dredging earlier this morning, the first tow on Viking Bank turned up nothing except a few chunks of mud.
Evening of 14th November: We’ve worked on two main sites on Viking Bank with variable success. Modern Arctica islandica here are small compared with specimens from earlier in the Holocene. This may reflect sea level rise in the area: early Holocene specimens, living when large parts of the North Sea were still dry land, would have been living in coastal environments, with more nutrients, and were therefore able to grow faster than is possible nowadays. These older shells have the kind of size and thickness that we see nowadays in Arctica from around the UK coast.
While some trawls turned up the older shells in large numbers, more recent specimens, and especially the live animals that Tamara was most interested in seemed to be more elusive. A small adjustment to the connection between the winch and the dredge may have had the effect of allowing the dredge to dig deeper into the sediment, and the final trawl of the afternoon shift produced about 30 live clams.