Leptoclinus maculatus: constant interest and increased company of fans

Hei!

Svetlana Murzina and Svetlana Pekkoeva pick up Leptoclinus from the bottom trawl

Svetlana Murzina and Svetlana Pekkoeva pick up Leptoclinus from the bottom trawl

 

Let me introduce to you our company of Leptoclinus fans: Stig Falk-Petersen (Akvaplan-niva and University of Tromsø, Norway), Svetlana Murzina and Nina Nemova (Institute of biology, Karelian research Centre RAS, Petrozavodsk, Russia), Camilla Ottesen (University of Tromsø), Jorgen Berge (University of Tromsø and UNIS). What is it about this small and tiny fish, Leptoclinus? Leptoclinus maculatus or daubed shanny is an ecologically important fish in the Arctic, with a complex and unique life cycle. Larvae are pelagic for may years and adults are bottom inhabitants. This fish has a serious program of adaptation to live in the Arctic. Larvae fed on Calanus spp. and convert (to be small and tender!!!) fats of one structure to beneficial fats of another structure, that is necessary for development and buoyancy, and concentrate the lipids (fats) in the special part of their body, the lipid sac. The lipid sac is, simply visible by eyes, situated on the belly of small fishes, and looked like a “honey comb” (according Morgan Bender, UoT) or a bunch of grapes.

Svetlana with lots of Leptoclinus

Svetlana with lots of Leptoclinus

After one year break of field activity and serious work in the lab, analysing daubed shanny ecology and biochemistry … but with inexhaustible interest to this fish we came back on the cruise to investigate the life strategy and lipid biochemistry of this tiny fish with thirst to get more fun. The break from the field sampling was successful for our international team of fans of Leptoclinus, we published three papers in scientific journals like,  Fish physiology and biochemistry, Polar biology and Journal of molecular sciences. New finding in the understanding of the fish reproduction, adaptation and ecology created new questions for further research.

Lab work on board R/V Helmer Hanssen

Lab work on board R/V Helmer Hanssen

Now we fulfill our dream to continue the research in the RCN funded SpitsEco project. Good news… our company of fans increased, we have new PhD student Svetlana Pekkoeva (Institute of Biology Karelian Research Centre RAS, Petrozavodsk, Russia) which were touched to the bottom of her mind by the story of this tiny fish living in the Arctic and she decided to join our scientific team and enjoy the research.

Written by: Svetlana Murzina.

Developmental stages of Leptoclinus maculatus

Developmental stages of Leptoclinus maculatus

Last day on RV Helmer Hanssen

The road map to Polar night studies started to develop before the International Polar Year more than 5 years ago. The ARCTOS network took part in many large IPY programmes, but none covered the darkest period of the Arctic winter. In 2006 we published a paper on Diel Vertical Migration during the Arctic Summer based on the data from an acoustic instrument (ADCP) mounted on the Observatory in Kongsfjorden. The year after, in 2007, the acoustic data from the observatory showed a clear diel vertical migration pattern of zooplankton during the Polar Night from November to March. After discussion and literature research it became clear that there was very little data, and a clear lack of knowledge and understanding, of marine life in the Arctic during the Polar Night. This triggered a large interest in Polar night biology of the Arctic Seas.

Then the self-appointed spiritual leader Jørgen Berge coupled up with gadget freak Geir Johnsen and the trip to the moon started. After they decided that the sun was not important, it was the circadian rhythms – but of course that was too boring: the moon was more interesting, and since then all was about the moon. The moon now rules the word, werewolves hunting in the dark, bioluminescence enables winter sex, and the fish with the largest balls swims in the deep, the bowheads have found the treasure at the rainbow’s end where the aurora sings during the polar night.

On this 7-day Polar night cruise we have been joined by scientist and students from Russia, Poland, Sweden, Scotland, England, Spain, Martinique, Denmark, USA, Germany and Norway. Participants represent several research projects, including MarineNight, CircA, MicroFun, Polarisation, and SpitsEco (see http://www.mare-incognitum.no/). The cruise also contributes to the University of Tromsø course BIO-8510 ARCTOS – Marine ecological research cruise to Svalbard (http://www.arctosresearch.net/) and AB-334 Underwater Robotics in the Arctic Polar Night  given by UNIS (http://www.unis.no/).

Paul Renaud and Stig Falk-Petersen

Bloggers of the world unite! Day 4 on Helmer Hanssen

18.01.2014

We’ve spent the last three days throwing a lot of equipment and gear into the water to detect whether or not marine life is active in the polar night. For the mooring team aboard Helmer Hanssen the first three days have been very busy recovering a mooring in Isfjorden and deploying two moorings in Kongsfjorden. Meanwhile the plankton team has deployed a variety of nets into the water to see if there is anything out there in the dark waters of Kongsfjorden.

We’ve been chasing zooplankton using two techniques – acoustics and nets.  Acoustics tell us where the animals are, and nets tell us what the animals are. The acoustics on the moorings allow the constant monitoring of the zooplankton through the year. It’s a bit like what the NSA is doing in the rest of the world, but we just focus on the Arctic.

There has been surprisingly good illumination over the past days with a full moon and the first hints of light appearing at noon towards the south. We still await for enough light to reveal the skyline behind Ny Ålesund. But mostly it is dark, and since we work around the clock catching up with sleep at random times we all are somewhat lost in time with only the meal times providing some sort of day rhythm.

Before we left Longyearbyen our spiritual leader (Prof Berge) had left with the full moon running with the werewolfs. Where does he get the blood from is the big question for these investigations.

Colin Griffith, Finlo Cottier, Malin Daase, with guest comment by Stig Falk-Petersen

Saturday the 18th of January 2014, somewhere on Kongsfjorden

Sooo what happened today…

… about  50 L of seawater was filtered so far for different kind of stuff… such as DNA, RNA, POC/PON and Chla…and it will be over 100 L at the end of this day!

… Chlorophyll was measured in huuuuge low amounts (but something is there!)

… about 2000 Millions of krill (or more precisely a huge amount of krillgrøt)  was fished from the 100 Millions of zooplankton nets.

… Poo production of zooplankton was supposed to be measured…but there was no shit found in the experiment buckets.

…a lot of mud was taken out of the fjord, at a time of day where run-of-the-mill human beings are normally sleeping, but not many life forms were found in it.

… an epi-benthic sledge was deployed, and so far it didn´t break – huge success!

… one midwater trawl was taken and too much just small fish were caught…and krillgrøt! Going for the big ones later on…

… AND quote of the day by Daniel: ”For those who´re going to Ny Ålesund tomorrow and have dirty clothes…wash them on board, you can dry them on land. And for those who are dirty, shower on board before you go on land.”

Cheers from Helmer Hanssen,

Trine, Miriam, Kajetan & Mikolaj

Epibenthic sledge catch. Picture: Kajetan Deja

Epibenthic sledge catch. Picture: Kajetan Deja

Chlorophyll a measurements

Tove and Anna measuring Chlorophyll a. Picture: Miriam Marquardt

Svetlana and Sveta happy about all the small fish

Svetlana and Sveta happy about all the small fish. Picture: Miriam Marquardt

Fish group on sofa

Fish group passed out in the canteen area. Picture: Miriam Marquardt

Krillgrøt

Krillgrøt. Picture: Trine Callesen

Epibenthic sledge deployment

Epibenthic sledge deployment. Picture: Kajetan Deja

Krill

Krill. Picture: Trine Callesen

 

A fjord full of krill

Krill. Picture: Gérald Darnis

Krill. Picture: Gérald Darnis

When most people think of krill their first thoughts are of Omega-3 capsules and food for whales in Antarctica. Whereas at least 4 species of krill are abundant around Svalbard and in the Barents Sea, they have rarely been found in high abundances in west coast fjords. Thus, we were surprised to see dense concentrations of highly active krill in Kongsfjorden in the middle of the Polar night. What sustains such activity? Their primary food source from spring to autumn is thought to be phytoplankton, which are all but absent at this time of year. Their guts show no evidence of any recent food consumption, further mystifying Polar-night researchers. Are they living from lipid reserves, or perhaps consuming transparent microorganisms like protozoans? This remains to be determined.

Krill are a central player in the CircA project, which investigates circadian rhythms in zooplankton during winter, their causes, and ecological consequences. PhD stipendiate Julie Grenvald is on board Helmer Hanssen tracking their daily abundance rhythms throughout the water column, sampling for analysis of their feeding preferences, and preserving samples for later genetic analyses. Gérald Darnis, a post-doctoral associate on the CircA project, investigates their role in carbon and nitrogen cycling. Finally, these high abundances of krill are accompanied in the water column by predatory fish, such as Atlantic cod, polar cod, haddock, juvenile herring, and juvenile redfish. The presence of such an active food web with krill as a central player during the Polar night is one of the most exciting discoveries of this expedition. But like all new discoveries, it leaves us with more questions than answers.

Gérald Darnis, Julie Grenvald, Paul Renaud

First day at sea

Fig 1: Packing at UNIS (Picture: Anna Vader)

Fig 1: Packing at UNIS (Picture: Anna Vader)

We left Longyearbyen the evening of the 15th of January after a busy day of packing amazing amounts of heavy research equipment on board R/V Helmer Hanssen (Figure 1. Packing at UNIS). We even packed a ton of water and a pallet of hay needed in Ny Ålesund!

After arriving in Kongsfjorden early next morning the deck became the scene for frantic activity. Because this is a short research cruise, our sampling schedule is unusually tight. Every type of sample will be collected both around noon and around midnight each day. The major event of the day was the deployment of a mooring equipped with acoustic loggers (Figure 2. Deployment of the mooring).

Fig 2: Mooring launch (Picture: Ronald Berntsen)

Fig 2: Mooring launch (Picture: Ronald Berntsen)

These will continuously log the vertical movements of zooplankton for the duration of the campaign.

All other sampling schemes (for example water samples, plankton nets, Video Plankton Recorder) also started up during the day.

Both net samples and images from the Video Plankton Recorder showed large amounts of krill in the fjord. (Figure 3. Krill pictures from the VPR).

Svein Kristiansen, Fredrika Norrbin, Anna Vader

Fig 3: Krill captured by VPR (Picture: Frederika Norrbin)

Fig 3: Krill captured by VPR (Picture: Frederika Norrbin)

Fig 3b: More Krill captured by VPR (Picture: Frederika Norrbin)

Fig 3b: More Krill captured by VPR (Picture: Frederika Norrbin)