Tuesday, February 24, 2009

AT WORK: STATIONS B, F and G




We arrived at station B around 3 p.m of last Thursday where our sampling activities started. The scheduled activities were to recover the time-lapse camera free-vehicle system and to deploy a couple of box cores and one megacore sample cast. All successfully accomplished!
The retrieval of the mooring line with the camera tripod attached to it was successful and relatively fast. It took less than 2.5 hours to locate (using the transponder and strobe light attached to the top of the mooring mast) and to put the heavy (0.5 ton) free-vehicle assembly back on the ship’s back deck. The anxiety to see the results of this seven-month experiment was evident in most of our team member’s expressions. Soon after the camera was retrieved, Craig and most of the crew were back in the E-lab to download the pictures from the camera and quickly back up all the data files into hard drives avoiding the loss of such precious scientific research material. A quick scan of all the pictures revealed that the mission was successfully accomplished. High-resolution photographs were taken at 12 hour intervals revealing megafaunal behavior on the sea-floor over the food-poor Antarctic winter. However, a failure in the system was noticed after the 4-month period from the start of the deployment. For some reason that is still baffling all the electronic technicians aboard, the camera stopped shooting after November 30 leading to a two-month gap in the dataset. Not too bad considering we have captured of the most important four months of the the intended 7-month seasonal period.






Since the camera is now not operating in a satisfactory way to conduct the yo-yo surveying transects, we had to change our programmatic plans of going to station AA and rather steam further south to retrieve our second camera tripod, deployed last winter at station G. Once we recover an operating camera, we can continue performing the photographic transects in which we collect bottom photographs at an average 20-second intervals and along kilometer long transects across the seafloor.

But before going all the way south to Station G we had first to stop at Station F since sediment incubation experiments were still not completed and Rebecca, our colleague from North Carolina State University, had to finish experiments from Station B before arriving at G, to make room in
the cold van (an actual shiping container adapted to be a cold room with temperatures set to ideal conditions for deep-sea animals). (Look at our site map at the top right side of the blog page menu bar, which indicates the position of all 5 oceanographic stations we are surveying in the
Western Antarctic Peninsula).


Last night we retrieved the first Blake trawl, which kept our colleagues busy for quite a while in the aquarium room sorting the catch and separating the animals for tissue dissections.. The Blake trawl scrapes along the seafloor and came up full of mud and our dear friend Protoelpidia (kindly named ‘Sea Pig’ due to its surprising resemblance to the terrestrial mammal), tubiculous polychaetes, and isopods.
We had a busy night also with the megacoring activity going on in parallel on the back deck, which also kept a few members of our group occupied for many hours slicing sediment cores to collect macro-invertebrates and sedimentary microbial biomass.
We will be back with news from our next activities onboard the R/V L.M. Gould and the outcomes of our sampling stations E, F, B and AA.

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