As promised we are back with revelations about our last challenges at station G and also with news from our fantastic success at station E.
So let’s first start from the exact point we left you guys last time. It was 7:00 am when the first epi-benthic sled sample came on board at station G. The whole deployment took about 2.5 hours to be completed since we have to wire out three times as much cable as the actual water depth. We are surveying roughly at 600 m deep in the Antarctic shelf so we need at least 1800 m of cable to drag the epi-benthic sled over the sea bottom.
Anyhow, there were some bets put off in the white board in the O-1 deck about the success or fail of our first sled tow. A few people were not very trustful in the proper functioning of the sled, betting the small and delicate collector net inside the sled frame would come back to surface torn apart. I put my bets on a complete successful deployment, which turned out to be the actual outcome. The result was then tons of species to sort, with potentially new records to science; but not only that, I got also 18 free beers, since together with Victor and Joseph we were the ones who bet in a 100 % success recovery. Plus I know how Dave (one of our PI’s from North Carolina State University) is very good at ‘maneuvering’ all the gear over the sea floor, using all the information available about the ship speed, the tension on the cable, and of course a good communication with the our pilots on the bridge.
The epi-benthic sled represents a historical mark in the deep-se benthic studies, since his first developers completely changed our view about life in the deep-ocean. After sled samples were collected for the first time in the late 60’s, the deep-sea was mostly viewed as a hostile environment that could not bear a great deal of biological diversity. Darkness, extreme cold temperatures and hydrostatic pressure were thought to be great barriers for life to develop. However, after the sled samples were sorted and hundreds and hundreds of new invertebrate species were found, this general idea about a diversity-poor deep ocean floor started to vanish.
And here we show you a little sample about why the deep-sea is today considered one of the most biodiverse biomes in the planet. The sled sample we collected at station G came packed with life, with hundreds of specimens of isopods, amphipods, (little crustaceans) polychaetes(segmented worms) and mollusks. See in the pictures below:
" Professor Thomas Dahlgren of University of Gotemburg and myself: sorting the animals at the microscope room"
“Annelid worm from the family Nepthydae”
“Annelid worm from the family Hesyonidae”
“Annelid worm from the family Paraonid”
“Annelid worms from the families Sigalionidae and Polynoidae”
We had another 12-hour transit from station G to E, further north, stopping shortly at station F for a yo-yo camera and also an epi-benthic sled tow. It took us less then 2 complete days to finish all the work at E; much faster then the previous two stations, which took us 4 days in
each to complete all the sampling. Extremely good news is that our camera system is now operating with a new bottom switch contact system and taking very good pictures of the sea floor.
“Sample of a sea floor photograph take at station G”
That’s it for now. We will come back later with our next adventures further north at stations B and AA. ALOHA folks!
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