Helicopter flights and seal-tagging attempts

Everyone who has had the opportunity to put on a helicopter survival
suit knows that “easiness-to-get-into” and “comfortable-to-wear” were
not high up on the designer’s agenda when they were created… but I’ve
managed to crawl into  one of them and I’m waiting together with Mia and
Horst to get into the helicopter for today’s seal tagging expedition.
It’s my third – the first one was not very successful. We had to fly far
to find an ice floe large enough that we would be able to land on it –
and when we finally found it there were no Weddell Seals to be found.
Plenty of seals, but the wrong ones. Karsten, the pilot, flew back and
forth across the ice floe, from one black seal dot to the next – but the
dots were repeatedly identified as “Crab-eaters” by Mia or Horst.
Crab-eaters feed in the surface water, while Weddell Seals dive down to
the bottom to find food. That’s why the latter are ideal as
oceanographic helpers  – we put a small sensor hat with an antenna on
their head; every time the seal dives down to feed it collects  a
temperature and salinity profile, and when the seal later rests on the
ice, the data is transmitted back to us via satellite. Since the Weddell
Seals stay in the pack ice all year, we can obtain salinity and
temperature data throughout the winter – when it is impossible for
research ships to reach the area.

Back to today’s expedition, which started out better than my first one –
it didn’t take long before Mia spotted a Weddell Seal and we were on the
ice. But before we had sorted our gear and changed to our
“work-on-the-ice-clothes”, the seal had slipped into the water and there
was nothing to do but to  crawl back into the survival suit and find our
seats in the helicopter. Mia soon caught a second Weddell seal in her
binoculars, and we were down on the ice again – only to realize that it
was a juvenile, too small to be tagged. Horst quickly returned to the
helicopter, clearly disappointed. Mia and I admittedly enjoyed the
encounter with the youngster and lingered with our cameras. Contrary to
the older, very lazy seals, this one was curious and clearly interested
in the strange two-legged red-dressed creatures that walked into his
lonely, white world.

Too small to get a tag – but very cute!

We were soon up in the air again – and found what seemed to be the ideal
location. Three Weddell Seals within what seemed like walking distance.
The helicopter took off – and there we were, all alone with our bags… on
an ice floe in Antarctica! We soon realized that the ideal location was
everything but ideal. The ice ridges and the glittering snow around us
was breathtakingly beautiful – but likewise breathtakingly hard to walk
across. When the closest seal turned out to be a second juvenile (just
as curious and cute as the first one), we soon had to give up. The other
two seals where too far away – if we would even be able to find them
within the maze of ice ridges.

Chilling out in the helicopter before take-off.

It was three disappointed, tired and very hungry seal taggers that
returned to Polarstern that evening – but we soon cheered up when we
learned that yesterday’s seal had started sending data, and that the
weather forecast for tomorrow promised good flight & seal tagging
conditions.

What a morning! Moorings recovered after 4 years!

Lucy, my cabin mate, has worked by the CTD half of the night so she is
fast asleep in the bunk bed below me when I sneak out and head up to the
bridge just before seven. It’s a beautiful morning. Scattered ice floes
around us, and a few ice bergs by the horizon – but the people on the
deck are more interested in the screens than in the view. Svein, a
colleague from Bergen, comes over and lets me know that they’ve seen on
the “fish-finder”. “It” is the mooring I deployed here four years ago,
and I’m utterly relieved to hear that it is still here! There are so
many things that can go wrong when you deploy moorings in Antarctica –
especially when you have to wait four years before you can pick it up!
When  the captain finally arrives, he glances out at the ice and gives
the permission to “release”. A few commands on a computer – and an
acoustic signal is sent out telling the “acoustic release” on the
mooring to drop the anchor. A few minutes later there are a couple of
orange buoys mingling with the ice floes a few hundreds of meters in
front of us.

Two orange floats that made my day!
Finally back in safety on board after four years in the water!

Two hours later, everything is on deck and the ship is streaming on to
the next station. I’m not sure what is happening there – but I know what
I’ve got to do. I’ve got four years of data to download, but first I’ve
got to wash away four years of biology that has colonized my
instruments!

Ninja inspecting four years of biological colonization.

Greetings from 70S

We are finally here – in the middle of the Weddell Sea! The eternal
quarantine is over, the long flight across the Atlantic is behind us and
all 92 of us have boarded the ice breaker Polarstern without bringing
any Corona-viruses with us! No more masks, no more tests, no need for
social distancing… it actually felt quite strange to go back to
“normal”!

We had a tough start heading out in the Drake passage from the Falkland
Islands a week ago – straight into the famous furious fifties and the
screaming sixties… I was far from the only one who did not show up for
dinner the first night at sea! but we are now steaming southeastward
across a relatively flat Weddell Sea, and the waves and the sea sickness
is easily forgotten when enjoying the view outside the window. Majestic
iceberg scattered around the horizon, sea birds flying along the side of
the ship – and if you stay outside long enough you are likely to spot a
whale or two break the surface.

Enjoying the view and the sun during a well-deserved break on deck

We are not here to enjoy the view though – and there is hectic activity
downstairs in the labs to get everything up and running before we reach
the southern Weddell Sea and the Filchner Trough where the majority of
our work is to be carried out. Equipment is being tested and installed,
labs are being built, batteries are changed and instruments are
programmed.

The CTD with its 24 bottles are going down for the first time at the test station.

Yesterday the ship stopped for a “test station”, so that everyone who
wanted to could try out their equipment. There where quite some
technical hiccups – but luckily there is still a couple of days to sort
them out before the real work begins!

The CTD-data are displayed in real-time as the CTD descends towards the bottom at the test station – and the oceanographers are watching the first profile with great interest . We quickly realized that the sensor for fluorescence and the flash from the instrument that photographs particles in the water were interfering, so they have to be moved further a part before the next cast.