Author: Mari Heggernes Eilertsen

It has been 10 days since we left Tromsø. Being so far out at sea is truly an experience that will stay with us for a long time. The feeling of having several kilometers of water between the ship and the seabed is quite strange and takes some time to get used to. Since we left, we’ve not seen any other signs of humans – just the waves, the seabirds and the samples we get up from vents. 

The days have been well spent, we’ve mostly been working in the lab or watching the streaming from the ROV. It’s been interesting to see how Mari, Tone and Nadia have been working in the lab – and we believe we’ve picked up a trick or two. Seeing how much work and knowledge that is required to understand the vent ecosystems and to find new species, has been inspiring. It has been good to get a hands-on experience out at sea. Because of the need to treat the samples quite quick to preserve them, some days of working in the lab have been longer than others. But by prioritizing which samples to treat first and plan shifts according to this, we managed to get it done – and the good working spirit has definitely helped us along the way. 

The deep-sea is among the parts of the planet we know the least about, mostly due to the difficulty of getting there. Today, we can overcome that by using an ROV, but still – there is 3 kilometers between us and the vents. There is always many factors we’ve needed to take into consideration, also factors that are outside of our control. The weather has been somewhat challenging and sampling with an ROV requires that several systems works perfectly together.  

Let’s not forget to mention the joy of getting to know the fellow scientist onboard. It’s been fun exchanging knowledge and learning about the interaction between chemistry, geology and biology. In conversations, there has always been a person with deeper knowledge within certain topics and there have been many discussions to engage in. 

Now we both embark on the journey of writing our master thesis both regarding the vent and seep-ecosystems – and we are excited! There is so much to learn about, especially in order to understand how these ecosystems might be affected by disturbances. 

Thank you for letting us join – it’s truly been a memorable experience. 

Marte & Haakon

Over the last two weeks, the Vent & Seep project has participated in the annual cruise of the Centre for Deep Sea Research, along with other projects like Eco-Safe Ridge Mining and DeepSeaQuence. This year, the cruise visited 4 vent fields – Ægirs Kilde, Fåvne, Mohns Treasure and Loki’s Castle – and the main aim for the Vent & Seep project was to collect samples from the various vent fields to get material for faunal inventories and DNA barcoding.

We were very fortunate to of have Dr Nadia Rimskaya-Korsakova with us in the fauna lab, who specializes in the morphology of siboglinid tubeworms. We kept her very busy with the various siboglinids we collected, and we are looking forward to seeing her future work on the material from the cruise! She was also a great help with the general sample processing, always making sure that all the samples were happy and sufficiently cooled while waiting to be processed.

We also had the pleasure of having two master students with us – Marte and Haakon – who are both writing their master thesis as part of the Vent & Seep project. Marte is going to study the fauna of arctic cold seeps in collaboration with the AKMA project, and she will investigate the degree of overlap between vent and seep fauna in the arctic region. Haakon is going to study fish from the Arctic Mid Ocean Ridge, using both sampled specimens and image analysis, to try to answer if certain fish species are more associated with the vent fields. 

Having Marte and Haakon in the lab was a great resource, and it was fun to see how fast they learned the skills of sieving samples with a careful hand, spotting small animals, and writing precise labels and sample protocols. But the best thing about having them in the lab was their endless good mood, sense of humor and impeccable taste in music.

It has been a truly enjoyable cruise with a great team of scientists working together to make the best of the time we have at sea. We are very grateful to have been part of it and look forward to next time!

A song of Ice and Mud

Currently, the Vent & Seep Fauna project (represented by Mari Eilertsen, and collaborators from UiT and University of Aveiro, Portugal) are participating in an Arctic cruise organized by CAGE/UiT and the AKMA and OceanSenses projects. Our main goal for the Vent & Seep Fauna project is to get good samples from cold seeps to generate species inventories and DNA barcodes. But as a part of the team of the cruise, we get to take part in many other fun activities on board!

One of our first stations was actually not for seafloor samples at all – but for samples of sea ice. And this meant showing off the icebreaking capabilities of the RV Kronprins Haakon by moving in to the sea ice until we found a spot with thick enough ice to walk on. And after the ice-team had taken their samples, those who wanted got to take a quick walk on the ice just for the experience.

And what an experience! Watching the ice move and crack while the vessel plowed forward, the sounds, the colors, was really powerful! And of course, standing on the ice, knowing you have several hundred meters of water under your feet, was just amazing.

After finishing the ice station, we moved south-west to the Vestnesa Ridge, where there is a cold seep known at around 1400 m depth. But before we start sampling the cold seep, we used the multicorer to sample a reference station – which is very important to understand the background communities outside the seep areas. And this was a very muddy experience – the multicorer came up with tubes of mud that was split between the different scientists to perform geochemical, meiofauna and macrofauna analyses.

Playing with mud is a messy business, but also a lot of fun, and there are always some cool animals hiding in the mud! Here are some of the critters we found at the reference station: two polychaetes in the families Maldanidae and Ampharetidae. These families also have some species specialized on hydrothermal vent and cold seep habitats, so fingers crossed that we see more of these in the active seep sites!