Cruise report from our master students

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

CDeepSea cruise 2022

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.

The team in the fauna lab. From the left: Mari H. Eilertsen, Marte L. B. Klemetsdal, Nadia Rimskaya-Korsakova, Haakon A. Pedersen and Tone Ulvatn. Photo by Pia Ve Dahlen (Lei en biolog).

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!

The whole team with cruise lead Pedro Ribeiro in the front.

AKMA-OceanSenses cruise pt 1

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.

Happy biologist on the ice!

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!

Creative outreach at OPPLEV Marineholmen in Bergen

The University of Bergen celebrated their 75th anniversary last year, and in connection with that, they organized a large science festival at Marineholmen in Bergen last weekend where they invited scientists to showcase their research to the public. We in the Vent & Seep Fauna project joined forces with other projects such as DeepSeaQuence and the Center for Deep Sea Research to present a stand focusing on life in the deep sea.

The various deep-sea content displayed on our stand. Photos: P. Hribovsek and MH. Eilertsen.

In addition to classical outreach activities, such as posters, HD video and a small exhibition of animals from the deep sea, we had an interactive activity which was hugely popular with the kids: an ROV sampling simulation. 

ROV-simulator in action. Video: P. Hribovsek.

The setup was very DIY with a webcam mounted on a simple mechanical arm (the kind that is used pick up something from the ground), connected to a computer screen. The sampling was taking place behind a curtain, and the person in charge of the sampling arm had to orient themselves based on the image on the screen only, which illustrated well the challenges of remote sampling. Behind the curtain we had bulilt a seafloor landscape with curious and colorful animals, and the task was to sample as many animals as possible within three minutes. The competitive aspect was a hit, and many kids enjoyed trying to beat the scores of their siblings or parents.

Our stand attracted a lot of audience and kids were lining up to try the simulator. Photo: MH Eilertsen.

All in all, we had a lovely day in the sun, with many good conversations with both kids and adults about the wonders of the deep sea, and we look forward to future opportunities to reuse and refine the ROV-game!

Sampling has begun!

This summer we participated on a research cruise to the Arctic Mid-Ocean Ridge (AMOR) with the KGJ Centre for Deep-Sea Research. This was the first cruise with dedicated sampling for the Vent & Seep Fauna project. Due to COVID restrictions, the cruise started a bit slow with a 10-day on-ship quarantine for all the participants. During this time the ship had to stay close to shore, but this allowed for some bonus-sampling for other projects in the beautiful Sognefjord.

Luckily no-one got sick during the quarantine, so after the 10 days we headed for the AMOR to sample some hydrothermal vents. We were only a very limited number of people on board this year, and the rest of the team tried to follow the dives from home with a live connection through Zoom. Even fieldwork has reached the digital age!

The main sampling-aims for our project this year was a comprehensive sampling of the Ægir’s Kilde vent field, and Mohns Treasure, an extinct vent field. At Ægir’s Kilde, there are multiple chimneys with white or shimmering, warm fluids streaming out. At the base of the chimneys there are amphipods and tiny snails, which are typically fund at hydrothermal vents on the AMOR. In addition we saw several fish relaxing near the vent. These fish belong to the eelpout-family, and are believed to feed on the vent-amphipods.

Fish relaxing near a hydrothermal vent chimney at Ægirs Kilde vent field

We also found some diffuse low-temperature venting with a bush of worms, possibly Sclerolinum contortum. We got some samples, and are looking forward to finding out what else might be hiding in this worm bush!

Diffuse venting and bush of worms at Ægirs Kilde vent field

The other target locality for the Vent & Seep Fauna project on this years cruise was Mohns Treasure. This is an extinct vent field, and one might wonder why we are interested in it? There are some records of species usually considered to be vent-specific that might still be found at extinct vent sites. It is possible that these sites might support some vent fauna, at least for some time after venting has ceased. So we wanted to get some samples to see if we find any overlap with our active vent sites. However, to our surprise, we found more than we hoped for! After flying around with the ROV for a while, mapping the area, we came across some diffuse venting. White bacterial mats were easy to spot, and when we zoomed in we could see amphipods and tiny snails that look suspiciously like the vent fauna we find at other sites on the AMOR. We got some samples, and morphological analyses and DNA-barcoding will tell us if they are indeed the same species.

Diffuse venting at Mohns Treasure with amphipods and gastropods

Despite the COVID-restrictions we were very happy with the outcome of this years cruise, and got a lot of good samples that will keep us busy!