Investigating the bottom

During five days of the cruise in Kongsfjorden we want to investigate the benthic environment. We will scrape the bottom, collect tons of mud with grabs and corers. Everything will be dirty. We will probably sleep for three or four hours a day. There will be a lot of fun.

Just a little part of bags, prepared before the  sampling station (Photo by Mikołaj Mazurkiewicz)

Just a little part of the bags, prepared before the sampling station (Photo by Mikołaj Mazurkiewicz)

But from the beginning. As it is good to be prepared, two days ahead our first sampling station we decided to start preparations of our equipment and all the containers for our samples. It seems trivial and boring, but it is very important to have everything prepared, especially since we had to label hundreds of string bags and tens of jars and buckets. Those last one needs to be labelled three times – on itself, on the cover and on the piece of paper that we put inside. A lot of writing. There would be no time to do this on the station during the sampling procedure.

Now we can start working. We begin with scraping the bottom with a triangle dredge. We are especially interested in rocks

Picking out the rocks collected in the dredge. (Photo by Joanna Legezyńska)

Picking out the rocks collected in the dredge. (Photo by Joanna Legezyńska)

and boulders on which encrusting and calcifying organism like barnacles or bryozoans (moss animals) grow. Three stations with three dredgings at different depths on each. Sometimes the work goes clean and smoothly but sometimes we get a material full of mud and we have to dig in it to find what we are looking for. But this is just a little part of our tasks.

Before I started my oceanographic studies I had supposed that sleds can be used just for fun. Here on Helmer Hanssen we have sleds as well, and they don’t remind regular ones, they are called epibenthic sleds and we use them to collect animals living on and above the bottom. But honestly… it also provides a lot of fun, animals we collect are so numerous and alive. And it is also very clean work – something rare in benthic ecologist job.

Struggles with the box-corer (Photo by Maria Włodarska-Kowalczuk)

Struggles with the box-corer (Photo by Maria Włodarska-Kowalczuk)

Ok, but what about animals that live in the sediments – the infauna? To collect them we need to collect hundreds of kilograms of mud. We can use a grab and then sieve everything. It’s the easiest ant quite fast procedure but it provides only big animals. Collecting smaller animals or investigating some properties of sediments like content of carbon or chlorophyll concentration in different layers is much more tricky. We need to use a box-corer, a huge and a little scary device that brings on the deck an undisturbed, rectangular piece of sediment. Then let’s put some tubes into it, cover ourselves with mud during digging to pull them out, and finally put them on the extruder. Than we can slice those cores however we like. From each slice we can take subsamples for different analysis. A lot of fun, at least five hours at each station. And then there is no time to rest! All those samples needs to be preserved, string bags with sediments must be closed, packed and stored in the freezer.

Besides collecting samples on the deck, there was also a lot of work under it. Some of the animals that we got with the epibenthic sleds had to be identified alive, and then frozen. Little unpleasant work, but on the other hand it is not so drastic as fixing them with a formalin. These animals will bed analysed for lipid and isotopic content. The result will tell us a lot about the diet of this organisms. Is it different comparing to summer? Do they change their eating preferences? We will see.

Five days passed and we survived. Even after such short time, a persons priorities can change a lot. Usual and ordinary concerns becomes much less important, you don’t think about groceries, paying bills or buying new trendy gadgets that everybody is crazy about. All you worry about is: “Will I find any time to sleep?” and “Will I finish working on the deck before breakfast?”. You do not worry if you are wearing dirty clothes. You don’t care if your t-shirt fits to your trousers, they just must be worm and comfortable. You forget about television, newspapers and even internet goes wayside, especially because the connection is so poor. You realise that earth keeps spinning around though you don’t know what did your friends post on Facebook recently and you didn’t see last news on TV.

Sorted animals ready for the identification (Photo by Mikołaj Mazurkiewicz)

Sorted animals ready for the identification (Photo by Mikołaj Mazurkiewicz)

We got MUD

We had an entire week to get ready, but today is the day. We finally got mud!

I guess benthic ecologists just never grew up and stayed young at heart… We do not say we are going to sample sediment; we say that we are going to play with some mud 🙂 This is probably one of the reasons why benthic ecologists are usually feared onboard scientific vessels: we really have fun! This plus the fact that we just get everything dirty everywhere we pass, sometimes even places where we did not pass…

In “regular” ships, in temperate latitudes, benthic sampling always takes place at the worst time of day, at night when all other scientific teams are resting between 2 and 6 am. But since we are working during the polar night, time does not matter and we sampled in the middle of the day – since it was night anyway.

During this cruise, we aim to sample 3 stations along a transect from the glacier to the open water. We came at other seasons, in spring, summer, and fall, and this data will complete the seasonal set in order to better understand seasonal changes (or not!) in benthic communities’ activities. In Arctic areas with abundant ice cover, benthic activities have been found to change as a function of seasons, with lower activities in the winter. However, in Kongsfjorden, where the ice has been declining so much, will the benthic communities change their activities?

To answer this question, we deployed a boxcorer, from which we subsampled individual sediment cores. Some of the cores will be sliced and frozen for future lab analyses of the characteristics of the sediment at that time (carbon and nitrogen contents, stable isotopes, pigments). The rest of the cores will be incubated in order to measure benthic activities: respiration, remineralisation of nutrients and bioturbation.

In order to stay young, benthic ecologists have a little secret that I will reveal exclusively here. You may wonder what we do with the rest of the mud from the boxcorer, and what is the link with staying young… Well, here is our secret, we use it as facial mask and therefore look younger! We call it the Arctic beauty. You may order it (20% to the first 200 people) contacting odup29@gmail.com

Mud picture

A part of the Marine Night group testing the new mud facial. Contact email above for more info. Photo: Nathalie Morata

Text: Nathalie Morata

Chasing Polar cods

Polar cods (Boreogadus saida) are the most abundant fish in the Arctic Ocean. They are perfectly adapted to the harsh unstable environments encountered at high latitudes and are believed to be an important link in the arctic marine food web. Their role as a keystone species also makes them a relatively well studied organism. That being said, much about the species ecology remains poorly understood.

My role on this cruise is to attempt to describe what polar cods feed on during the polar nights. More specifically, I am interested in the seasonal variation in polar cod’s diet in the Svalbard region. In order to do so, I must examine polar cod’s stomach content and identify the organisms they’ve ingested. This of course, involves in a first instance… Catching the polar cods themselves! This may seem a piece of cake when having the opportunity to board a ship such as the Helmer Hanssen equipped with trawling equipment, small mesh nets, and echo-sounder, but let us not be fooled. Chasing polar cod can often be a frustrating fruitless experience. Granted polar cods will most likely occur in “Arctic regions” (eg. Sill fjords, or fjords north of Svalbard) as opposed to “Atlantic regions” (fjords on the west coast of Svalbard) but they do sometimes occur in fjords influenced by Atlantic water inflow.

On this trip we will only visit fjords that are strongly influenced by the inflow of Atlantic water. In fact, most of our sampling will occur in Kongsfjorden on the west coast of Svalbard. Our first trawl was scheduled for Thursday the 8th at 2:15AM inside Isfjorden, right out of Longyearbyen. Although we got quite a number of fish, particularly atlantic cod, the polar cod catch was rather meagre (2 juveniles). We did have however quite a diversity of organisms in this trawl (including a number of benthic organisms) and spent a few hours sorting, identifying, measuring, and weighing. Paul Renaud helped us a great deal identifying the invertebrates and as always, the small spiny Parampithae hystrix was the mascot. The atlantic cod were surprisingly small. Carl froze the few skates, flatfish, and snail fish that we caught for further analysis. Pandalus borealis were dominating the catch in abundance with 262 of them caught in this trawl.

Even if there are no polar cods for me to analyze, a trawl does not go to waste. There are a number of projects on fish that will all claim a given part of the trawl content. Ultimately, all organisms (fish and invertebrates) will be processed and the resulting data will go towards a broader fish project taking advantage of any trawl happening on this cruise.

We are still at sea at the moment, sampling for zooplankton not far from the sea ice. The next trawls are scheduled for Kongsfjorden. Kongsfjorden, the fjord in which we destroyed the net in the past cruise when it got stuck in mud near the glacier. Hopefully, this time, mud won’t be at the rendez-vous and polar cods will be around.

Text: Marine Cusa

Marine with Cod

Successful cod-hunt

A Tourist destination

This is not what one imagines being on a ship, cruising around Svalbard, should be like. There are no dramatic vistas of sharp peaks, rocky shorelines, and glacier-covered mountainsides. Bears, seals, walrus, and sea birds have either left for more southern areas or are somewhere out of sight. It is dark. I mean really dark. Imagine crawling into your refrigerator (or more accurate, your freezer) and closing the door. If the light really does go out when the door is closed, that is pretty much what it is like here.

But then, we are not tourists either. In fact, it is this darkness that interests us since, in very recent years, it has surprised us with its high levels of biological activity. Planktonic and seafloor (benthic) communities, and even some seabirds, are very active. The interactions of sea ice, wind, and water now are , in part, determining the productivity of the ecosystem when the sun returns. We are here to study the biodiversity and ecological processes of the polar night to more fully understand how Arctic ecosystem’s operate.

So on second thought, maybe we are here for the same reason most people visit Svalbard: the mystery of a foreign environment that relatively few have experienced, and the feeling of being part of something far larger than we are. Our field of view is shortened, even in the lights of the ship or our headlamps, challenging us to look more closely at the details and letting our imaginations fit these into a bigger picture. So maybe the real sense of adventure and exploration of an unknown world that we are undertaking makes our voyage worthy of any tourist guide after all.

Text: Malin Daase, Paul Renaud

Helmer Hanssen with searchlights

Photo (Malin Daase): The research vessel Helmer Hanssen illuminates the darkness as it steams northward through sea-ice in the polar night.

 

January 6th, 2015 on board of the RV Helmer Hanssen in direction of Longyearbyen, Svalbard.

I won’t deny the soporific effect of the smooth rocking of a boat on its way to the Arctic Ocean, yet here I go, throwing myself into blog redaction and event reporting. Some of us haven’t been feeling particularly fresh ever since the boat left Tromsø yesterday after-noon and the captain sheered us up today when he announced that the seas ahead were quieter. A few minutes later, the ship pitched enthusiastically (just to prove him wrong) causing all sorts of stuff to hurtle across the “instrument” room including some of us attempting desperately to avoid the flying objects.

As casual as some scientists try and make this type of field work sound, it seems to me that describing it as an expedition would be most appropriate. A few numbers of us, professors, students, assistants, and a wonderful ship crew have embarked aboard an adventure that will last two weeks and that will take us into the depth of the Arctic everlasting winter nights. We will explore the ocean depths of west Spitsbergen fjords from the Helmer Hanssen research vessel. Darkness is a difficult world to grasp and to study, especially when it creeps in frigid isolated oceans, yet it is far from being devoid of life and wonders. Here, we will attempt to understand how organisms and ecosystems function in an environment that appears most frequently pitch black to the human eye. Each of us are appointed to one or several tasks, some of which are related to personal research projects. The research crew is quite international with scientists coming from France, Germany, the USA, the UK, Russia, Sweden, Poland, and Norway. This trip falls under the umbrella of the Marine Night project who’s ambitious goal is to provide insight on food web structure and marine biodiversity during the poorly understood Arctic polar nights. Thus, we will study a wide range of organisms, from foraminifera to polar cods, and take a number of important hydrological measurements throughout the duration of the trip. We will report on the daily activities aboard the Helmer Hanssen and will describe our projects and the organisms we study.

I am part of what we naturally called “the fish group” and will both be working on my own Master’s thesis on polar cod’s diet but also on an ongoing project indexing all fish species caught in the Svalbard region during the polar night cruises. I will describe both of these projects and the organisms they involve further down the cruise.

Text: Marine Cusa