[fusion_text]A journey to the end of the world… | Dr. Stefan Thiele

Dr. Stefan Thiele is a Postdoctoral Fellow in the Polz Lab. This winter, he was invited to join an expedition to Antarctica for a month to conduct research. Below is his account of the adventure.

A journey to the end of the world…well to be scientifically correct: There is no end to a sphere, hence, there is no end of the world. But this is Antarctica, and this is probably as far away as a person could go away from civilization. And for what? Science of course.

Let’s start from the very beginning. On January 30^th, I boarded a plane to Santiago de Chile. One day later, another plane to Punta Arenas. For a long time, this small port town at the Magellan Straight was actually the end of the world. And yet another day later, I’m sitting in yet another plane. But this is not any plane: it is a Korean charter with destination King George Island. So this is it, I’m seriously going to visit the last continent on my list. I’m going to Antarctica!

My first view of King George Island

On King George Island, in addition to an airport, there are also several Antarctic stations: one from Uruguay, one from Argentina, one from South Korea, the Russian Bellinghausen Station (including the only real church here), and the Chilean Station Escudero. This station, part of the only permanent Antarctic settlement called the Villa Las Estrellas, will be our home for the next two days. Unfortunately, transportation is slow and weather dependent, so we have to stay and wait. I use the time to get in touch with the locals for the first time: the penguins and the skuas. Luckily, I find a team of German ornithologists that allow me to stick around while they monitor and tag the birds.

View over Base Escudero (front), Villa Las Estrellas (left), and Base Bellinghausen (back).

Finally, it is time to leave for the final destination: Base Antarctica Naval Arturo Prat on Greenwich Island. After a few hours at sea, we arrive in Discovery Bay. In the morning, we are shipped out to the Base. And it is our lucky day! It is the 70^th birthday celebration of the base! So after storing our boxes in the room that will be our laboratory, and unpacking our backpacks, we have a party.

Birthday cake for Base Prat showing the whole base as a miniature version.

But we are not here to celebrate, so we set up the lab and start the experiments. The main focus of the project is on nitrogen cycling in Discovery Bay, and how climate change affects the uptake of nitrate, nitrite, and ammonia by the bacterial and archaeal community. We collect general data, perform a chlorophyll grid over the bay, and I do some labelling experiments using a thymidine derivate that’s incorporated into the DNA of active cells (bacteria and eukaryotes). So our two main jobs here are basically going out in zodiacs and collect water and data, and filter the water to get the microbial community.

Sampling out in Discovery Bay.

Preparing a Niskin bottle for water sampling.

Part of the sampling team. From left: Me, Choriqueso, Armada (both marines), and Giovanni (Master student at the University of Conception).

The first week basically goes by with initial explorations; first larger samplings to get some DNA and RNA for general metagenomes and metatranscriptomes from our main 2 sampling points. One of the points is in the open bay, but the other is close to a glacier, and thus influenced much more by the fresh water runoff and the ice which is discharged into the bay by the melting glacier. This is not an effect of the ongoing austral summer; the temperature are apparently higher this year than in the past. So we expect a large difference in the microbial community of the bay vs. the one close to the ice.

In addition, we set up the first experiments, including Nitrate and Ammonium uptake experiments using stable isotope probing, and my experiment, in which I labelled a natural community of bacteria and small eukaryotes with Bromdesoxyuridine (a thymidine derivate).

My experimental set up. In the water to provide environmental conditions.

My own experiment aims to investigate the food web structure of the so-called “microbial loop.” This is a very tightly connected food web of microbes that channel carbon in marine systems, before the carbon eventually enters the food web towards the larger organisms. The idea is to feed a labelled community and, in a similar set up, one specific labelled strain into a natural system and see how the label distributes, revealing the active predator community.

In addition, I sampled the viral community to see if the label also distributes into bacteriophages. My research aims to answer an environmental question; the question of how the run off of fresh water and the correlated desalination of the water due to climate change will affect the food web of the microbial loop. For the desalination experiments, ice from a nearby glacier needed to be sampled, which was a welcoming physical activity as compared to hours of filtration.

Sampling the ice on a nearby glacier and showing off my CEE pride!

But of course we have some other past time activities in addition to our research. On the first Sunday, we cross the bay to visit the people in the Ecuadorian Base Maldonado with the soldiers of the brigade that is stationed over the summer at Base Prat. Here, the “First Antarctic Olympics” take place. First, there was a soccer game; the Chilean team won 3:2. While soccer was fun, egg runs and sack races are other more strange sides of what you would expect in Antarctica. Particularly, if you keep in mind that soldiers of two different countries are representing their nation in the races. Well, maybe Antarctica is actually the continent of peace. It seems at least during the party afterwards, where both sides eat, drink, and laugh uniformly.

Sack race won by Chile with a fantastic picture finish by cook Gregory.

The next two weeks are very similar to the first two. The experiments continue and the sampling trips go on. Most hours are spent in the lab with tedious filtrations in more or less functioning systems. Only visits at the icebergs that thrive in the bay and the occasional appearance of a whale, seal, or penguin during sampling make the days a bit more interesting, but this gets especially hard when the weather changes and the wind freshens up.

Between the icebergs.

Some fun in the lab. Giovanni, Choriqueso, and Estrella.

The commander of the base decided a few days before the weather got really bad, that his guys and we should get out and visit the local penguin colony. So we all ship in to a small island at the beginning of the bay and walk to a nearby beach full of penguins. During the briefing before we left Punta Arenas, we were told that you should not disturb the animals and always stay at least 5 meters away. Well, nobody told the penguins! We are quickly encircled by these curious creatures.

Curious Gentoo penguins plan to apply to MIT CEE in the future.

Before we, and also the summer brigade, leave the station, one last thing has to be done. “Antarctic baptism.” This is not a traditional Christian ceremony where somebody blesses you and sprinkles holy water on your forehead. In this ceremony, you go a few meters out into the bay with a zodiac, and one by one you climb the tube of the boat, somebody paddles you on your backside and off you go. Swim back to the shore in 2°C water.

Of course, an interesting experience requires a huge party with BBQ and piscola. A nice ending for an intense, amazing, and very interesting stay at a Chilean naval and research base. Two days later we board a ship and leave the island, back towards King George Island. Unfortunately, we get stuck here for 4 days, since the coordination of weather, Antarctic survey and military is too difficult to get us on a plane to Punta Arenas. However, this is a good time to reflect about the adventure and enjoy a last few nice days on the continent so far away in the South.

This trip was sponsored by Beatriz Diez Moreno from the Ponteficia Universidad Catolica De Chile in Santiago, Chile. The official title of the research Stefan worked on is “Shifts in marine Antarctic microbial community in response to deglaciation and ice melting” and is funded by the Programa de Cooperación Internacional DPI20140044; CONICYT, Chile.[/fusion_text]