Information
Comments
This second phase of CEAMARC benthic sampling started very well with 6 stations completed in the last 24 hrs. We have now caught up with the planned sampling schedule, having 24% of sites left to do and 25% of the total time allocated to CEAMARC to do them in. If the weather remains kind to us we should complete the schedule as planned. The only slight variation being the re-location of some sites to avoid dense pack-ice on longitude 140E directly north of the French research station at Dumont D'Urville. We have also re-aligned some sites, on the basis of very accurate bathymetry obtained using a multi-beam swath mapping depth sounder, to get better series of samples from shallow to deep. Yesterday's samples from 400m, 800m and 1100m were a very interesting contrast to those from a similar depth series reported in sitrep 321, which at 800m was dominated by a colourful garden of filter-feeding coralline species. Yesterday's 800m site had a very sparse covering of surface-living filter-feeders, such as sponges and bryozoans, but had very large numbers of Macrourus whitsoni or rat-tails, a common fish from these depths throughout the world. The sea-bed photographs indicated a lot of 'marine snow' (organic particulates) in the water and a piscean wall of mouths - fish waiting on the seabed for food to be washed past them by the currents. So although only 20 miles apart and sharing the common characteristics of very high productivity and biomass the benthic fauna at these sites were intriguingly different. Regards, Martin and Sarah.
Map
A map showing Australia and Antarctica. The map shows the journey of one voyage that has occured in the season, with each route highlighted in a distinct colour.