Oceanographic Campaign

Icefish

I would like to remind everyone that my trip to Antarctica was not (only) for fun!

So after a few delays due to the weather, and after finally finding all our crates and containers on the Lion, we started out on the campaign.

The main lab container, with the disassembled IKMT net in front.

Our main working ground was the rear of the water-level deck, used mainly for cargo transport, and called the garage. This has a large overhead panel, which opens to let the crane maneuver the cargo in and out, and 2 rear doors. The main rear door is quite large, but has a 70cm sill (otherwhise it floods), which makes moving things out onto the rear deck a bit of a pain.

Astrolabe with the main garage door open.

Our 'lab' was commosed of 2 small containers. The first, near the back doors of the garage was for the formalin and sorting of the larger animals. The second, with a little window, was at the back of the garage, and so a bit warmer and a bit quieter. That's where we did all the precision sorting and identification, chlorophylle filtration and coffee breaks.

Orange formalin container, right, and the rosette of bottles, left.

Interior of the main lab container.

There were 5 teams on board: one doing whale watching from the bridge; one doing the physical parameters of the water; one geology group doing sediment cores; our group fishing for stuff; and one group doing physiological studies on any krill they could get from our nets.

Interior of the krill tub.

This means the boat time had to be split, equally if possible, between the different groups. This was not as easy as it sounds, as we did not all want stations in the same places, and also as we were sampling the zone which used to be close to the Mertz.

B-9B

The Mertz is a big glacier a bit to the East of Dumont d'Urville. It used to have a large tongue of ice going straight out into the sea, and creating a very interesting area on its western size, with retention zones for fish latvae, etc.... Unfortunately, there is a huge iceberg (called B-9B) which has been roaming around East of that since 1987! And last year, its roaming brought it into a collision course with the Mertz. Not only did the B-9B completely break the glacial tongue off, but it has become stuck (for now) just West of where the Mertz tongue was.

All that yellow on the radar is ice! How fun!

Scientifically speaking, we had a block of ice over 300m thick and about 97 x 30km across, which just happens to be sitting on half of our station points. Well as there's not much you can do about that, so we just did what we could around it!

And what we did was:

Water samples, with measurements of the physical parameters of the water (temperature, salinity, etc...), with a rosette of 12 bottles.

The bottles can be closed at different depths, and we then recuperated the water and filtered it, to catch all the small phytoplankton present in the water. The chlorophylle concentrations on the filters are then determined in the lab. I will note here that the Ricard bottle is not part of the official scientific protocole, but turned out to work much better than the plastic keg originally planned.

Sediment cores

A small-meshed net (WP2), in which we mainly got phytoplankton soop.

Seawater, above, and what came out of the net, below...

2 small-meshed nets next to each other

(called Bongo nets because they look like bongo drums).

They were also filled with phytoplankton but we still had to sort through one of the buckets to get out the few fish larvae that were inside.

And finally a large net! The IKMT (for Isaacs Kidd Midwater Trawl) is a super nifty net to fish with, but rather a pain to set up. However, a new technique was used for storing it, in its own box, and that seemed to limit the amount of tangling it could achive between uses.

The IKMT, as well as being a beautiful net,

aslo yields catches of the utmost interest and amusement!

And it is in fact in the IKMT nets that were found most of our precious fish (the cook and various ukrainian crew members had to be forcibly manhandled to a safe distance of this catch),

and my even more precious jellies!

All this makes it sound as if we were working full tilt for 2 weeks. However, for every person working, there were usually at least 2 photographers.

And of course when off shift, we had plenty of leasure time to raid the dining room for M&Ms, observe the wildlife and enjoy the sunset.

Some of the hundred giant petrels that took to following the boat one day.