08.02.2013 (Friday). When I wake up, it is really gloomy outside.
Ice interspaced with wide polynias under a thick dark hazy sky. Later on, the
ice coverage increases to become nearly complete and the sun appears; it is
shining brightly on the icescape. There are leopard seals around. One is to
starboard, to the bow of the ship. We succeeded to make good pictures of it.
After many days, we do our next Agassiz trawl
(East of Joinville), at about 470 m depth. It comes back full of blackish soft
mud, with an evident smell of hydrogen sulfide. Very little life in our catch.
Strange holoturians. Two phoxocephalid (Pseudharpinia
antarctica) and one eusiroid (Oradarea sp.) amphipods, one Ceratoserolis, 6 Antarctomysis and some Notocrangon,
and that's all for crustaceans. Just after the trawl, we deploy the dredge.
Same kind of bottom, so same kind of poor catch: only two amphipods. In the
evening we deploy again the trawl and the dredge in the same area, this time at
shallower depths (around 250 m). The bottom consists of mud mixed with stones
and gravel. The catches are much better
but yet not extraordinary. The sorting in the lab starts around 24:00...
Icescape.
Leopard seal.
Agassiz trawl on deck.
Notocrangon antarcticus is one of the very few species of Antarctic shrimps. It is a common species which likes muddy bottoms.It reaches about 100 mm.
The amphipod Pseudharpinia antarctica (about 20 mm) also seems to be a mud lover.
Dredge coming up from the deep blue.
Untying the bag of the dredge.
Emptying the content of the dredge in a bucket.
Removing everything from the dredge.
Upper sieve and its content, after cleaning with sea water.
We and our dredge.
Our faces after working on deck with mud.
(Cédric)
08.02.2013 (Friday)
The first Agassiz
trawl is deployed in the station Joinville East deep (about 435 m) around 10
am. When I was waiting for the trawl to go back up, somebody tells me that a
leopard seal is in on an ice-plate just in front of the boat… I inform the
people I meet on the way and run for my camera and then on the front deck. At
first, I have to lean a bit over the barrier to see it, the animal is much
bigger than a crabbeater and the head is huge: no doubt it’s a leopard. The
seal is moving and the boat too, so I get the chance to see the animal
entirely. The head is disproportionally
big compared to the rest of the body, with an enlarged mouth drawn in an
everlasting nasty smile, undoubtedly hiding a set of large and sharp
teeth. He looks at you with this vicious
expression fixed on his face, as if to say “I would really like to eat you
right now”. I felt happy at the moment to be safe on the boat and not on the
ice-plate close to this imposing predator, with its monster-like appearance.
Leopard seal.
I have to leave the impressive
creature to gather on the working deck with the rest of the benthos
people. The trawl is slowly put out of
the water. We instantly notice a bad smell of hydrogen sulfide, meaning that
this mud is probably quite anoxic. At first glance, it indeed seems that
there’s not much life in this sticky (and stinky) brownish cream. When we look up more closely, sieving the mud
and digging into it, some animal groups are quite abundant, like polychaetes in
consolidated mud tubes and holothurids. But others are rare or completely
absent, and we only found 4 amphipods in
this catch. So, not much to work on in the afternoon, but we have another trawl
planned for later in the evening. We deployed the dredge also at the same spot,
but the catch wasn’t much better, only a few amphipods to add to the list.
In the evening, the catch is
delayed, it takes place quite late, around 10 pm. I like to work outside around
this time anyway because the sky shows very beautiful colours when the sun
begins to settle down around 11 pm-midnight. And you really don’t feel tired
with the excitement of sampling and the light as if it was middle afternoon.
The catch was really nice this time. A lot of beautiful fishes, among which
ice-fishes. They have colourless blood due to the lack of hemoglobin, not
needed in the oxygen-rich waters of the Southern Ocean. I always wanted to see
that and it’s true that when you look at the gills, they are white, not the
usual red. A huge starfish, I didn’t know starfishes of this size even existed!
The first ray also, cartilaginous fishes aren’t abundant in the Southern Ocean.
The amphipod catch was honorable and kept us working in the labs until 4 am.
Giant starfish!
(Marie)
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