TANGO scientific expeditions

During the Tango 1 expedition, an important part of the projects relies on samples and data collected by SCUBA divers. Our diving team is composed of Francesca (UGent), Martin (ULiège), Lea and Camille (ULB).

Antarctic waters are a first for all members but Francesca, and previous training was an important part in the planning of the expedition. First, all divers needed to obtain a European Scientific Diver certification to be able to carry on research underwater. The team then trained in Belgium using the same tools they would use here, around the Antarctic Peninsula.

Diving in Antarctica mainly requires the ability to cope with freezing-cold water. For this, the dry suit is a must and is completed by multiple layers of thermal underwear and warming equipment. Luckily, Belgian weather can offer extreme diving conditions, with quarries and lakes reaching down to 4°C during the winter. Our team was therefore well prepared and did not suffer from more than a few cold fingers.

On-site they collect specimens, sediments cores along with pictures and videos to document the expedition.

The Team is leaving tomorrow for the first expedition of the TANGO project, to the Grandidier Channel, in the West Antarctic Peninsula, onboard the RV Australis (A motor sailboat operated by Ocean Expeditions, Capt. Ben Wallis).

TANGO1 is about understanding ecosystems responses to climate change in the Southern Ocean, and in particular trying to identify tipping points (at which ecosystems can drastically change in terms of structure and function) using a holistic scientific design.

TANGO1 is about exploring areas which are poorly documented, understood and inventorized, in an informed fashion and yet are undergoing accelerating environmental pressure.

TANGO1 is about coherence in terms of environmental impact. We want to lead by example, as we use a sailboat to carry marine science work in an extreme environment. RV Australis will allow us to reach particularly low levels of GHG emissions and habitat disturbance during sampling operations.

TANGO1 is about agility. Our sailboat allows us to reach shallow areas, and make fast decisions as we adapt to the conditions we will be meeting in the field.

TANGO1 is about commitment. We pledge to be in complete immersion in the environment we will be studying as we are convinced this will contribute to raise awareness about the importance of nature conservation.

We are leaving tomorrow, crossing the Drake Passage to the Western Antarctic Peninsula for a month of fieldwork.

After a full year of training, I am very excited to bring the ROV to Antarctica and finally explore the Southern Ocean seafloor.

When buying the BlueROV2 last year, we had no idea how much technical problems we would encounter. After 3 pool sessions (thanks to the David Lloyd and our dear Fabienne), multiple sessions in the “Vrouwenpolder” and the “Spuikom” (with thanks to Watersport Ostende Spuikom), a trip to Chile, another to Corsica and a final dive in the quarry of Barges, I think we pretty much discovered all possible problems and fixed them, learned about best practices and of course the importance of making check-lists (and reading them before departure…).

Let’s hope everything goes well once we’re there!

Lea

When people ask me what I do for work, I reply “I am a marine biologist”.The excitement then brings about the second question “oh wow! What do you study?” and often this initial excitement is soon killed off by my second answer : “sediment and worms” 😉 but not always though, I still manage to convince people of how awesome my job is!  Yes, I am one of those scientists to whom sand can speak and who find delight exploring a hidden world which cannot be fathom by the eye, but it needs a microscope and lots of patience to be witnessed and discovered. I work with soft sediments and a size class of organisms that live in them known as MEIOFAUNA…animals – yes, animals : they are multicellular, have organs and “limbs” a bit like us but are super tiny and they pass through a mesh sieve of 1 mm!!. Since the beginning of our cruise B121 I have explored during my dives the shallow bottoms of each location we have been visiting seeking for sand and mud. I have set out to collect sediment either by means of cores (plexiglas tubes which use vacuum to bring back on land a perfectly intact piece of the sea bottom!) or simply by scooping the surface of the sea bottom where sediment patches could be found.  What do I wish to find out by looking at these communities? I want to see what is their overall biodiversity in between the different sites we study since there are many different animals that live in the sediments in that size range, and their presence or absence from one location can tell us a lot about the health of the sea bottoms, for instance about how well is the recycling potential of the sediments doing in relation to the glacier retreat activity. It sounds very scientific right? But at the end of the day, I am just a girl having fun underwater and playing with mud on the surface! Look at this picture of me and Ryan (first mate on board) setting up my outdoor laboratory in the back of the Australis where I was dedicated  a little space to where to make it dirty for a little while!​

Among the many research projects conducted during the B121 cruise, trophic ecology has taken an important place for divers and fish specialists all along the campaign. But what is it about ? Beyond the formal and bit severe words, trophic ecology can be simply and instinctively recapped by the famous idiom “you are what you eat” ! Every single piece of snack each of us ingests or drop of liquid we are happy to sip not only contributes to maintaining our whole body in good shape but also, and insidiously leaves its indelible mark in our organs. This holds true for all living beings and for isotopes as well ! Analyzing the composition of organisms in Carbon, Nitrogen and Sulfur stable isotopes can tell us a lot about the long story of what they usually eat and where they have been living. Eventually, analyzing the isopotic composition of organisms living in close vicinity to each other in a same place can help unreveal biological interactions between them in the food chain that is, who’s eating whom and what. That’s why specimens of some common and key species of the visited sites were sampled at the sea bottom, from seaweeds to sponges, worms, starfish, sea urchins and fish, to caracterize main food web elements and compare them between sites. The complexity of food webs is also a condition of ecosystem resilience facing climate change, the more redundant and complex biotic interactions are in a food web and the more likely the ecosystem is to resist to change. Let’s wait a bit and see what isotopes will tell … !

Thomas

Alongside the numerous samplings done every day during the expedition, a timeframe is also dedicated to macro-photography. There, a different world can be revealed from what we cannot see with our poor human eyes…

“Wow, this little guy was a flatworm and not a leech“ or “Hey, look at this structure on the right, it is key for the identification “ are just two examples of B121 exclamations associated to someone looking at a macro-picture. 

That’s the key advantage of macro-photography: it gives you precious information to identify the organisms onboard (or after the expedition). Last but not least, this is also a good resource for future scientific publications and outreach activities.

That’s why Quentin (Jossart) is spending few hours every day to capture the most common or interesting species collected throughout the day. Photographing them alive is an asset because some structures or colors can deteriorate after preservation. A lot of patience is thus sometimes needed as some animals are constantly moving… “Please mate, stay here a seecccooonnddd” is the most polite exclamation that has been heard from the dedicated photo-area onboard.

Four men in a small rubber boat. Drifting away and fishing. Tied to a
small iceberg. Somewhere in a channel with ice-cold water, between 5 and
150 meter deep. To the north, rugged, steep mountains, interspersed with
glaciers that look as if they may topple any second. To the south, a
very shallow and flat archipelago with two penguin rookeries. Our
operating base, the Australis, is anchored there.

We haven’t caught a single fish all day. Suddenly, a pack of crabeater
seals surfaces directly next to us. They play around in the turquoise
water of the iceberg and loudly recharge their lungs with fresh air.
“Where are all the fish?” we ask. The seals snort and shoot perhaps one
or two curious glances at us, but otherwise we’re being thoroughly
ignored. We value their company nevertheless.

A few hours later – the sun has already dropped behind the horizon – 
our final effort at this locality pays off: the small net we set out in
the morning brings us ten fish. At last. A happy moment, because these
are valuable samples that will allow us to conduct detailed studies on
the diet and genetic make-up of this species. Such information is
ultimately important to understand and protect the unique Antarctic fishes.

…

When it comes to spending four weeks with 11 persons on a small vessel
such as the “Australis”, details, compromises and organisation are key
to enjoy the voyage to Antarctica.
Finding your own space in tiny cabins, sharing one shower or dealing with your cabin mate snoring are all details that become part of a daily routine that we all (have to) embrace.

Working on such an unusual platform requires good organisation to
satisfy every project and person that is part of the expedition. Sharing
“laboratory” space, zodiacs, sorting trays, etc., … can be tricky when
many operations happen at the same time and good coordination and
communication among the team is important to avoid any conflict. Our
daily routine therefore always ends with a debriefing to discuss science
as well as planning or personal feelings.

The most important assets to live on the “Australis” can be summarised
into three major points that, as we all agree, make the success of our
expedition.

First is Katie, who’s in charge of everyone’s happiness inside the boat.
She is the one we will have to blame if we put on too much weight during
these four weeks. She is the British sister of the boat, always asking
if everything is fine and offering goodies for comfort. She also proved
herself a brilliant biodiversity catcher on Antarctic shores.

Then comes Ryan, mostly dedicated to outdoor activities, he is always in
for a zodiac lift, assisting the divers, going fishing and making sure
we are all safe when conducting our science. Never short on a funny
comment or joke, this New Zealander and Katie are like cats and dogs in
the galley.

Last but not least is Ben, captain of the “Australis”. His huge
experience of the surrounding environment ensures the success of
location picking while satisfying every project on board. Entirely
dedicated to the Belgica121 expedition he always finds a way to help us
achieving our goals.

These aspects are certainly only the tip of the iceberg – the three of
them work day and night to run the “Australis” without us noticing and
all this work in the shade is probably the most important part of the
success of the Belgica121 expedition.