Sunday 23 December 2007 à 09:04

First trawl!

Par Sophie Mouge. Correspondent aboard the Aurora Australis

We all wake up at dawn this morning. Well, it’s just a figure of speech since, as you realize, the sun has decided not to set now! Fortunately the curtains over the portholes are thick enough to provide a semblance of darkness.

Setting sun that does not really set.

Catherine was careful to waken her colleagues (more and less easily!) so she wouldn’t find herself alone sorting the contents of the first trawl, which being hauled up three hours earlier than planned!
We don’t even take time for breakfast. Everyone gets to the trawl deck, ready to sort the contents of what will soon be brought up.

Waiting for first trawl catch.

The first operations are always impatiently and nervously awaited, for veterans of oceanographic missions as well as neophytes. The wet lab is full of people for the occasion, which limits how much we can move around.

Thomas Silberfeld, Samuel Iglesias and Marc Eleaume still in a clean uniform!

Maneuvering the trawl, or any other fishing gear, is potentially dangerous. That’s why access to the trawl deck of the ship is forbidden to anyone not qualified. So we watch the trawl being hauled in from the wet lab that’s located just a few steps away.

The trawl laid on the rear deack just after being hauled up.

Trawls are historic fishing gear. They include a sledge with a metal brace 1.5 meters wide that glides over the ocean floor and collects the top few centimeters of sediment. The Aurora Australis tows the gear over 420 meters of bottom for about three minutes, at a speed of one knot. That corresponds to a surface trawl about 100 meters long.

The trawl brings up a pile of mud to sift through.

The net that has been dragged behind the frame is full of compacted mud that now must be sifted to find out what’s inside it. Using shovels or hands, the researchers get hold of pieces of mud and rinse them in sieves to separate the living organisms from the loose substrate in which they live. This exercise is very physical because the volume of mud that must be sifted can be substantial. After sifting, jars full of marine organisms are carried inside the wet lab to be sorted, sometimes photographed, conditioned and carefully arranged for their upcoming journey back to the National Museum of Natural History in Paris.

The mud is sorted in the wetlaboratory.

There is no lack of helping hands for this first trawl. The sorting goes pretty quickly so we can all get together for dinner. The other members of the mission are amazed and stupefied to see such a diversity of organisms brought up in the nets. They ask us a lot of questions: “What is it? Is it a new species? Was it already found in this sector? etc.”
Indeed, with this very first trawl we have already caught a species of teleost fish never before found in the region.

Lycodichthys dearborni.

It’s obvious that Sunday on board a ship is not a day of rest. We have to profit from every moment available for work. Every day is thus fully packed but the working conditions are so extraordinary that we overlook the fatigue that sometimes spreads through us!

Penguins on pieces of ice floe.



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Water temperature: - 0,6 °C
Air temperature: - 2,5 °C



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