We have been extremely busy in March on board of the Polarstern and we did not had the time to update the blog. However a detailed logbook has been written during that period (at least by me) and a lot of photographs have been made by us. Our narrative of the expedition will be completed but this will take more time than expected. I am already back in Belgium, but Marie is still in Patagonia and will only arrive in early April. We have a lot of other things to do, and the content of the blog (at least the part concerning the expedition itself) also has to be checked and approved by the scientific leader of the expedition (for justified reasons). So, please be patient and expect a long update at an undetermined date in April 2013.
(Cédric)
Wednesday, 27 March 2013
Thursday, 7 March 2013
28.02.2013 - colourful giant amphipods
28.02.2013 (Thursday). The trawl
of today was quite unusual. The station was the deepest so far : 770m, so we
were expecting (and hoping) to find some different kinds of animals than the
usual. When the trawl was brought back above the working deck, everyone was
surprised to see an enormous amount of mud in the net. The deck has never been
so dirty. At first we cannot see anything, so it´s always a surprise to wash
some of this mud and see if there´s something in it. There was a lot of
organism hidden in there: seestars, a lot of ophiurids, sponges … and
amphipods. Not so much (or most probably we couldn´t find them so easily in the
mud) but really interesting ones. We found some Eusirus giganteus of an unusual coloration. I did my master thesis
on the pseudocryptic diversity inside this genus, so this interested me a lot.
We found out during my thesis that the species of Eusirus can most probably be distinguished with the coloration,
along with other less visible morphological characters. There was a species in the complex giganteus of a bright red coloration
that we called the “red dragon”. At first, I thought the specimens we found
today belonged to this species, but the coloration is still different, the body
is grayish with blood red appendices. It´s another piece of the Eusirus problem, and raises even more
the interest in continuing the study of the genus.
In the
evening, I dissect the first serie of specimens of interest for my Phd thesis,
in order to begin the DNA extractions. I withdraw one or two pleopods and put
them in absolute alcohol. At the end, the work with the stereomicroscope begins
to get very hard, as the sea is getting rougher and rougher. We make sure that
everything is fixed and attached with ropes, because the night will be quite
agitated, with a wind of force 9. Indeed, we are woken up around 4 am by a
violent bump that makes everything fall on the ground in the cabin. I sleep
real bad, I´m probably not used anymore to such movements but I fortunately don´t feel any
seasickness.
(Marie)
28.02.2013 (Thursday). Oh, its already the last day of February.
Time is running like a meteor on the planet Antarctica... In the morning, same
weather than yestrerday evening: foggy. The wave are moderate but are supposed
to increase seriously later today. We are at our second sampling area in the
Bransfield Strait. We will again do three or four stations here at various
depths and at bottom topologies for estimating the influence of these
parameters on the structure of the benthic communities. Today we will have our
deepest station so far: about 770 m depth. The net comes full with a huge load
of brown pasty mud. It does not smell. We find a lot of Eusirus of the complex giganteus.
Most of them belong to the chromotype 'gray back/crimson legs', not yet found
during this cruise. Truly giant amphipods reaching 100 mm with a vibrant
colouration.
In the coming days we will probably have a second trap operation. So
we need more ballast (piece of rail of 50 kg). They have rermained in a container
in the hold. The second officer Felix Lauber told me that there is a problem.
The main door of that container has been soldered. The other door can only be
slightly open and only a narrow-chested man can go inside. This will be
difficult but normally it will be possible.
In the evening, the strength of the waves increases considerably. We
have to fix everything in our lab (and the dredge outside). Waves hit the
window of our lab. During the night, I hear in my sleep that the telephone and
the bin of our cabin fel down and are rolling from one corner to the other.
Marc, who sleep below me, put them in security in a safe corner.
(Cédric)
Eusirus complex giganteus, chromotype gray back / crimson legs.
This is the tip of the spine of a cidaroid sea urchin. There are tiny bivalve molluscs and holothurians (the pink sausage) living specifically on them.
Detail of the same.
27.02.2013 - Traps coming up (updated)
27.02.2013 (Wednesday). My clock was supposed to ring at 07:00.
Apparently it did but I did not hear it. At 07:25 I emerge from the sleep as
Marc Eléaume puts the light on in our cabin. I get up with difficulties. We
have the time to take our breakfast and we go out. Weather ouside: open sky,
not cold, some waves but not high. The Agassiz trawl is up around 08:25.
Content dominated by sponges. Also small stones, hydrocorals and crinoids. The
sea-urchins people are happy because they get enough of their spiny
friends/victims for their physiological studies. We do not get so many
amphipods, but some interesting like Echiniphimedia
gabrielae and the 'slender spines' form of Echiniphimedia hodgsoni. We suspect that the form with slender projections
and that with robust projections are two different species but we never had the
opportunity to test if they are indeed genetically different. If so, one should
be one more on the list of our undescribed species to describe.
Echiniphimedia complex hodgsoni, species/form with slender projections/spines.
Our traps put at sea yesterday are supposed to be relased from the
bottom at 12:45. However we are in advance on schedule. I am asked by the crew
to release them from the sea floor around 12:15. I rush outside with the
telecommand. I deploy the cable of the hydrophone, connect it to the
telecommand. I send the message of release to the acoustic larger. No reply
message! Oh ghosh, what's happen? The reason is simple: the hydrophone has not
been put in the water and in my excitation, I did not realized that! We put it
in the water. I load again the telecommand. A few second later I send the
release message. Two VERY long seconds and the telecommand makes a bip. The bip
means that the lander has been released. Good! It comes up at a speed of about
1m/s. The depth is 180 m. The conditions of visibility are excellent. About 6
minutes later the lander is seen at the surface, on starboard, ahead of the the
ship. Some ropes of the system are grasped by a hook and fixed to a side crane
of thye ship. The lander is hauled up and put on board. One strange thing: the
flag pole has collapsed and is now twisted as a huge spaghetti. How is this
possible? Careful examination reveals that the flagpole was not a metal stick
with a light plastic sheath as I thought but was entirely in plastic... Marie,
who did not realize that the releasing operation happened in advance of the
time schedule, does arrive. Once again, she will see the operation on video. We
remove the traps from their fixation system. we release their content in
plastic buckets full of cold sea water: hundreds of amphipods and isopods. The
bait was not fresh and we left the traps in water for 24h instead of 48h
(optimal duration according to empirical observations). I was expecting
thousands. Anyway, the main point is not the quantity but the quality. We will
see. I first have to get rid of the bait from the bait boxes: plastic boxes of
8 cm with small holes allowing the smell to spread out but limiting the
possibility of consumption, ...at least for large and mid-sized specimens. Some
small hungry crustaceans managed to get inside the bait boxes anyway. There is
even a small isopod passing its head through one of these tiny hole and looking at us with a comic
expression. I will not look for those guys, who entered the boxes: I throw away
all the stinky half rotten fishes and the gourmets feeding on them. We will
have enough work with the rest.
In the wet lab, we put all the scavenging crustaceans from the trap
in a white tray with cold seawater. They will mostly concern Charlotte
Havermans from our museum (amphipods) and Christoph Held of the AWI (isopods).
We carry out the pre-sorting. First we take out the isopods (Natatolana spp.), then we look for
amphipods (all from the superfamily Lysianassoidea except a single Oradarea sp.) and separate them in five
categories distinguishable by the naked eye. The representatives of these
categories are in fairly similar proportions: a large species with white eyes (Parschisturella carinata), a large
species with elongated red eyes (Tryphosella
murrayi), a medium-sized specieswith non-elongated red eyes (Hippomedon sp.), a small compact species
(Orchomenella pinguides), a large
dark-eyed form (provisionnally
identified as Pseudorchomene plebs).
We go to our dry lab with the specimens. I realize that, when I
made pictures and videos of the recuperation of the traps, I kept the setting
of my camera for the macrophotography of specimens: all my pictures are
strongly overexposed and could be uploaded on this blog only after a delicate
Photoshop therapy. I will try to not repeat this mistake the next time.
We look at the specimens, make photographs and put them in properly
labelled vials with absolute alcohol (best fixation for DNA studies. Under magnifying
lenses, I detect a few specimen of an additional species with red and white
L-shaped eyes referred as Tryphosella group macropareia. Then a big surprise. I was already starting to fix what I believed to be a
pure sample of Pseudorchomene plebs,
i.e. by far the most abundantly amphipod collected in baited traps in
Antarctica. Then my eyes are catched by the unusual tinge of the eye of one
specimen. I look at it under the dissecting microscope. Its eye is
silver-coloured instead of being dark brownish red as in P. plebs. Furthermore the dorsal process of its first urosomite is
slightly more angular than in P. plebs
(something that only a trained or very careful eye can perceive). I take a good
series of specimens and look at them one by one under the dissecting microscope.
The specimens can clearly be separated into two categories by the eye colour
and to a lesser extent by the shape of the first urosomite. There are actually a lot of specimen of that sliver-eyed species. Due to lack of time,
I cannot identify them immediately, but on March 7th, I looked again to them and I identify them as Abyssorchomene charcoti.
At 22:15, the fog has fallen on the sea.
(Cédric)
27.02.2013 (Wednesday). We wake up at 7 am for the Agassiz trawl. Outside, the sky is completely clear of
clouds and the moon is full. It’s still a bit dark but the sun will soon go up.
I find it very unusual to see the moon so clearly with so much daylight
already. In the far, the Antarctic Peninsula
appears progressively as the light increases. It’s like an irregularly shaped
shadow in the horizon. We can even see the shadow of a ship in front of it,
apparently a fishery boat. The sky turns pink above this piece of land, which
makes the whole scenery very surrealistic. It was worth getting up so early,
also for the catch. The trawl brought up a lot of organisms of all sorts, very
clean, and everyone got some interesting material. Less amphipods than
expected, but with the material we already gathered this week, we can´t
complain. We don´t have time in the schedule for a dredge, but today we have to
recover the traps. I am quite exited about that, it´s something new for me and
always a surprise to see if it worked well. The cage wasn´t hard to find back
and was brought on board without any problems. We can soon see a lot of tiny
animals moving in a remaining layer of water at the bottom of each trap. The catch
was successful, the quantity of animals can apparently be higher, even though
it seemed already a lot to me, but the diversity of species was quite good. It
entirely consists of necrophagous amphipods and isopods, as we put pieces of
dead fish in the traps. The amphipods all belong to the super-family
Lysianassoidea, although it can happen that other kinds of amphis get trapped
“by mistake”. The ZDF team was there to take pictures and film the recovery of
the traps and the processing of the catch, as it´s a gear that we don´t deploy
so often. We´ll maybe deploy it 3 or 4 times tops on the whole trip.
Afterwards, we separate the different species in the wet lab. It takes a lot of
time because there are so many animals and we have to pick them up one by one.
Then, we fix them in ethanol for molecular studies.
(Marie)
The lander has come back to the surface.
Sorting samples from the traps.
Tray with hundreds of amphipods coming from the six traps put on the lander. You can se the reflection of the light that we use for a better preliminary sorting of species and categories. During the preliminary sorting, we pay a special attention to the shape and the colour of the eyes of the amphipods. This requires sharp eyes. After that an examination under the dissecting microscope is usually necessary.
Pseudorchomene plebs usually comes in crowds into the traps.
This time, Abyssorchomene charcoti was also found in large number in the traps. Its silver/gray eyes allow easy recognition under the microscope, but not with the naked eyes.
Monday, 4 March 2013
26.02.2013 - Finally the traps are put for the first time at water
2013-02-26 (Tuesday). After a night of hard work, I was hoping to
sleep until 10:00. However at 09:30, Julian Gutt wakes up me by a phone call,
because there are different things to fix before dealing with the technical
aspect of the traps. I take a shower, put my clothes, quickly eat a pancake,
drink a cup of coffee (I cannot sart without a cup of coffee) and runs to the
office of the meteorologist. He tells me that the weather for the coming days
will be windy (for short periods up to 8 Beaufort) and with waves (for short
periods of time up to 4 m high). Not optimal conditions, but this is still OK.
I got to the bridge and discuss with the pilot (Carola Rackete). We fix an
approximate position for putting the traps (at 180 m depth) and decide of a
time for getting them up (in a time interval of 24-48h). She told me that due
to the bad weather conditions, the system should be improved for removing the
lander more easily out of the water. I say that in such coçnditions, we
should add a rope with a buoy to the upper
frame. She says this would be OK. I see the boatman (René Schröter) to
see if he has such a gear. he confirms me that he has it. We untie the lander
and its ropes. We fix the acoustic releaser to the ballast of 100 kg. We have
to put the gait (fishes) in the traps. I have defrost them yesterday (for the
second time). They stink horribly. Marie put rubber gloves and cut them into
pieces with very shears and put pieces of fishes in boxes with small holes,
which are fixed in the traps. I am a bit ashamed to leave this unpleasant task
to Marie but there are several things to do quickly at the same time and other
urgent duties called me. I test the radio beacon with Carola. It works very
properly. When I am back I see that Marie has received the kind help of Annicka
Elsheimer for cutting these horrible fishes into pieces. Their stench is so
intense that it has escaped the wet lab and is now spreading int the
corridor... I was fearing the justified irritation of colleagues but nothing
like that does happen. We bring the trap outside and fix them on the frame of
the lander. Then we screw the radio
beacon to the upper frame of the lander. Everything is almost ready. I hurry up
for eating (it is 11:40). I go as soon as possible back into our lab. I prepare
my camera (I have to change the battery and the objective). I put the radio
beacon and the flash on. I note and photograph the frequency of the radio
beacon. I fix the antenna of the radio beacon. Everything happens now very
fast. The system is put at water very quickly, in advance of the time schedule.
It should have started at 12:30 and the operation finished at 12:25. Marie did
not realized that. So she can see the immersion of the traps ... only on my
videos. just the time to write these lines and the Agassiz trawl is up. It is
13:25. Bottom consisting in fluid mud with gew small stones. Mud not smelly.
Sample not very diverse. Very big Paraceradocus
gibber. Some Liljeborgia georgiana.
I keep the fishes, which I freeze almost immediately, when I return inside
(just the time to photograph the colourless gills of an ice fish species
without hemoglobine). Next trap operation, I want to have fresh fishes, not the
horribly stinking fishes of this morning. the trawl for tomorrow was supposed
to be in the afternoon. So we hoped to be able to sleep longer than usual after
our previous short night. But at 20:21, Bruno David inform us that it will be
put in the water at 08:00. So not a too long night for us, poor exhausted
amphipodologists. I need to seat and to have one drink to relax a little bit.
Philippe Dubois erupts in the room and tell me with a big sardonic smile that the
trawl will start not at 08:00 but at 07:00...
Note to the layman, who reads those lines: such difficult time
schedules are absolutely normal in oceanographic cruises.
(Cédric)
The fishes of the family Chanichytidae belong to the notothenoids (or ice fishes); they are only found in the Southern Ocean and are characterized by their absence of hemoglobin. Their blood is colourless.
Mouth of the same fish. Neither the gills nor anything else is red as its blood is colourless.
Lander ready for its first immersion. The traps are the white plastic boxes at its lower part.
Labidaster annulatus is a common giant multi-legged starfish of Antarctic seas. It is sometimes over 50 cm leg span.
We would have liked to present more non-amphipod Antarctic marine organisms but unfortunately we rarely have time to take pictures of them.We also regret that the updating of this blog is very irregular but it cannot be done otherwise as we have a lot of work and it takes a lot of time to upload texts and (small) photographes from Antarctica (by a poor satellite connection).
Sunday, 3 March 2013
25.02.2013 - Improving the efficiency of the dredge
25.02.2013 (Monday). I wake up at 10:00. Pallid sun shining on an
open sea with scarce icebergs. Waves moderate. The door of our lab must remain
open and it is more or less fixed open. I say more or less: it is grating on
its hinges as the shipe rolls on the sea. This repetitive and irritating sound
makes me nervy. Yesterday I tried to
fixed it with small plastic collars. This morning I found them broken. I put a
stronger collar; I manage to reduce the noise but do notsucceed to suppress it completely.
The pictures of the OFOS underwater video camera seem promising.
The OFOS underwater camera.
The OFOS video camera directly transmits videos and pictures from the Antarctic sea floor at hundred meter depth.
(Cédric)
Monday 25.02.13
The Agassiz
is deployed a bit after lunch-time. The first trial was unsuccessful because
the net turned upside down and got caught in the metal frame, but when we
deploy it again, the catch is the biggest we´ve ever had. The dredge is very
successful too. The net is full of gravel and countless small amphipods, among
which some small epimerids-iphimedids that we didn’t catch before, such as Iphimediella dominici and Epimeria grandirostris. Also 3 specimens
of the very rare and very strange-looking Acanthonotozomopsis
pushkini.
(Marie)
Iphimediella dominici (7 mm)
Again a tiny species with a very long name: Acanthonotozomopsis
pushkini (5 mm)
24.02.2013 - Local sterility
Sunday 24.02.13
Agassiz trawl planned at 6 am. A bit before
7, we´re all set on the deck. It´s still dark outside. The fog is thick, so we
can´t see anything further than a few meters. The temperature rose again and is
now around 1°C, so it´s not so cold anymore for the work outside. When the
trawl is lifted above the ocean, I soon see a lot of mud getting out of it : a
big hole of a few meters-long is visible at the back of the net. A sharp rock
probably damaged the gear at the bottom. Everything´s not lost though, a fair
amount of mud and rocks is released on the deck floor. When we begin to sieve,
we soon realize than this sediment is completely sterile of life, no animals at
all can be found. After all the sieving and cleaning, we gather in the mess for
breakfast, as the catch was zero for everybody. Later during the day, it´s
decided to deploy the Agassiz again in the
evening at the next station.
The evening catch is more
successful. A lot of rocks make the sorting quite difficult, but some animals
can be found in the mud. We find for the first time some really big Epimeria robustoides, completely white
with bright red eyes. Some more spiny Epimeria from the similis complex, Eusirus
perdentatus and for the first time also, some Eusirus of the complex giganteus possibly belonging to different
species. We try to keep some of the fine sediment, to look for smaller
amphipods, but we find later that it´s quite poor and that the few animals we
can find have been badly damaged from the rocks in the trawl. However, the total catch keeps us working
until almost 3 am.
(Marie)
Epimeria robustoides, which can reach 45 mm is one of the largest and fattest Epimeria species.
24.02.2013. (Sunday). The clock of Marc rings at 06:00, mine at
06:10. Difficult to get out of my bed. Outside it is still pitch black. Indeed,
we use the time zone of Europe, which is not the same as the astronomical one
for the area. By the way this completely perturbs our biological clock. The
trawl is put in the water at 06:18 (same area than yesterday but on shallower
and flatter bottom, about 175 m depth).
I go to the mess room two. I am obviously in the way, but I really need
a cup of coffee to start to work. I go down. The winch is already going up at
06:40. Around 07:00, we are on deck. We see the very first light of dawn, but
it is still very dark. The trawl goes up. It proves to be badly torn (it will
need reparation) but apparently we did not loose so much of its content, as a
large compact mass of mud mixed with shingles and gravel, looking (in my
imagination) like the faeces of a huge dinosaur. To our surprise, this mass of
sediment is completely sterile. We get absolutely NOTHING in sieving it. I
order to cancel the planned dredging operation (it would me wasting our time
and that of our colleagues). This samples is of course disappointing for our
point of view of taxonomists, but it is also quite enigmatic from an ecological
point of view. Why such a sterility? Sometimes, we had poor catches, but never
such a sterility. As a consolation, I eat a solid breafast: fried eggs with
onions, bacon, mushrooms and ketchup (no tomatoes - they are all long gone) and
bread with eggs of forel. The sea is calm; the sky is gray; it is foggy, not
cold. As we are short of time, we will
make a second Agassiz trawl early in the evening (next station/environment of
Bransfield East). Julian Gutt asks me to use the Rauschert dredge fixed on the
side of the trawl and not separately. I do not like at all this idea because
previous experiences prove that this method increases the risk to loose the
dredge if it is stuck between rocks or if the net of the trawl twists as
yesterday. After further thought, I decide to skip the dredge operation because
I want to take no risk. The Agassiz trawl comes up with huge stones and a lot
of life. The first thing I spot is an Epimeria
robustoides. This is one of the biggest species of the genus (about 45 mm)
and a very fat one, snow white with the oral fields and anterior legs purple. A
really cute species. Later on, we find other specimens of the same species but
smaller ones. We also get Eusirus perdentatus
'spotted chromotype' and Eusirus
giganteus 'spotted chromotype'. No E.
perdentatus 'marbled chromotrype'. Too deep? Since we did not use the
dredge we sieve the sediment of the trawl. Not many animals in that fraction,
but Marie spots a very strange one (for specialists), which I can only identify
the day after, as Prolaphystius isopodops. I go to bed on 25.02.2013 at 02:45.
(Cédric)
23.02.2013 - First sampling in the Bransfield Strait
23.02.2013 (Saturday). Bad night, possibly because the ship is
rolling quite a lot in the true open sea, and certainly because I had bad
dreams. When I wake up, I see that the sky is cloudy again. Mid-sized waves
cross the sea. No more land, no more
icebergs (at least for the time being), only the sea. Our stations north and
west of the tip of the Antarctic Peninsula are now a closed chapter. From today
onwards we will be sampling in the Bransfield Strait and at the end of the
cruise we are supposed to work in the Drake passage, north of the South
Shetland Islands. So, today first station in the Bransfield Strait: Bransfield
East, slope, station 192. We should have started the trawling operations in the
morning but due to technical problems with other gears used before, it was
postponed early in the afternoon. I go on deck with the GOPRO camera. It is not
cold for Antarctica (a few degrees above 0°C). When the Agassiz trawl comes on
board, it appears that the bag of the net has turned over and is now stuck into
the frame. Yet during the short time, when it worked, it has collected
interesting organisms for us: Eusirus
perdentatus sensu lato ('marbled form' and the larger 'spotted form') and
three species of Epimeria: E. macrodonta sensu stricto, Epimeria similis and Epimeria aff. similis (again a probably undescribed species already found during previous
cruises). Despite I am still disappointed by the GOPRO, I get acceptable video
footages of the work on deck. Since the first trawling operation did not work
properly due to the net twisting, it is replicated. The second trawling yields
more or less the same crustaceans than during the first one. After that we use
the dredge. An immature chinstrap pinguin is swimming aroung the wire of the
dredge when it is hauled up. We get a sample of black muddy sand. Only
small-sized amphipods and not so many, but yet species not found so far during
the cruise like Lepedipecreoides xenopus
and Tiron antarcticus. It appears
that for an unknown but miraculous reason, the piece of my macro objective,
which had become disfunctional for days (something in the image stabilizer, I
think), unlocked and the objective works
again properly. I am more than happy because for days this camera problem had
badly affected my mood. Tomorrow, the trawl will be put in the water at 06:00.
So the night will be rather short for me.
(Cédric)
Epimeria similis (35 mm).
Epimeria aff similis (35 mm): one more undescribed species?
Lepedepecreoides xenopus (6 mm).
Tiron antarcticus (6 mm), seen from above.
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