Amgueddfa Blog: Research in Norway and the Barents Sea

You have not heard from me for a while because there has been little to report in the way of spectacular finds. The Barents Sea, at least the sector we are in, is a plain of muddy sediments at depths of 210 to 350 metres. That is not say that there is no life down there most of it is hidden in the mud and most are rather small and beyond the ability of my camera.

I thought that I should review where and what has been going on. Two images to remind you of where we are [1, 2]; in the second the oval area is the study area. The coloured images show the water depths from brown-yellow-green-blue from shallow to deep. Geologists also survey the area using a type of penetrating sonar that gives a picture of the structures in the seabed. This data is combined with the bathymetry and using this the geologists and biologists decide where to make their investigations [3] .

Two interesting features on the these images [4] : - first the long groove (top and middle left) is the trough made by a massive iceberg grinding into the seafloor probably not long after the end of the last ice age; secondly (middle and bottom rows) all the dots represent pock-marks made by methane gas flowing out through the mud and leaving a depression. It is thought the gas was trapped by the pressure of the ice during the ice age and when the ice retreated this gas was released all over the Barents Sea.

The animals that I am interested in often live around pockmarks but unfortunately most are now inactive. We did visit an area where active gas seepage has been found but we found no specialised fauna from our sampling. This area consists of two mounds [5] created by the slow upward movement of salt layers deep in the underlying rocks, called salt diapirs [6] these sites are often associated with gas seepage and unusual faunas.

Many thanks to Valerié Bellec for the multibeam images.

Having set the sampling grid the geologists using the multicorer [7, 8] take sediment samples and these are also used by a geochemist that looks for contaminants such as heavy metals. Here [9] Stepan (geochemist) washes down the tubes while in the background Sigrid and Valerie discuss what to do next.

You have already seen the video (CAMPOD) and beam trawl in action but the bulk of the quantitative data is gathered by the grab [10] . Andrey washes out the sediment through a 1 mm mesh in the auto-siever [11]; all animals are kept to be counted and identified later back at base.

All this data is combined in a GIS (geographical information system) system and maps of the seabed produced. These maps can show bathymetry, sediments, and geochemistry but here is one for the area off Tromsø showing a combination of sediments and faunas [12] . The faunas are recognised by the dominant species seen by the video combined with data from the trawl and grab. These maps are interactive and can be viewed on the MAREANO web site.

The MAREANO project is very ambitious but it will provide both scientists and decision makers with the information needed to manage the Norwegian Seas. The Barents Sea data will help decide how to manage the cod fishery and the coming oil exploration.

Finally its midnight through my porthole [13]

#1, the black pudding [1 & 2]

This 10cm long, purple black sausage shaped creature was in a number of the beam trawls. It’s not at all obvious what it is at first but there are 15 tentacles around the mouth and you can just make out five bands running along the body. These numbers suggest an animal with symmetry of five and therefore a relative of starfish. It is indeed a sea-cucumber (holothurian) of some kind and it will live by ingesting mud and feeding on the detritus in it.

#2 starfish and sea urchins [3 & 4]

These represent some of the more colourful and larger animals taken by the beam trawl and the starfish are easily seen on the videos. The muddy urchins you will not see, as they are burrowing creatures that we know as sea potatoes. Close up some of starfish show good protection from being eaten by foraging fish.

#3, too close for comfort? [5 & 6]

In this expanse of mud there are few place for attached epifauna to settle so even the smallest hard surfaces are colonised. The clams Astarte and Bathyarca both live close to the surface of the mud and their hind portions are often colonised by minute foraminifera and tiny hydroids and polyps. Here both have been colonised by a sponge that has taken over a large part of the shell but despite this the clams are alive and well.

#4 who’s in my house? [7, 8 & 9]

These exquisite tusk like tubes are built out of sand grains by the polychaete worm Pectinaria and are very common in many of our samples. But when you look at the opening many tubes are filled with mud and have a central burrow. Opening these you will find the peanut-worm Phascolion has taken over, it will also do this in empty snail shells and worm tubes. The peanut-worm does not eject the polychaete but settles and grows in empty tubes. In image 9 the grey sausage shape is the peanut–worm and the pink worm is the Pectinaria. What happens when the peanut-worm outgrows the tube I do not know!

#5 is it a coral? [10]

Without a scale these little calcareous parasols could be mistaken for a coral colony but the largest does not exceed a centimetre in diameter and are attached to small pebbles. Without the microscope it is difficult to see what they are but underneath the arms of the parasol there are rows of little cavities each containing an individual animal. This is a bryozoan and is more familiar to us in a mat or frond form.

After waiting for 36 hours we finally left port and headed north to the Barents Sea. The sea is incredibly calm [1] and now we are here it is also a strange shade of pale blue, not at all what I expected. All the time we are accompanied by fulmars, sitting in the water on our lee side [2] .

We have started at the northerly end of our transect around 72.5°N. At each station we carry out a video survey of the area using a trifid like camera array called the CAMPOD [3] . It is seen here being brought back into the hangar after its trip just above the sea bed. Inside the control room [4] the operators log all biological and geological features visible on the video displays. Sitting on the right Gjertrude controls the camera while Geno enters data into the log, behind on the computer is Valerie, one of the geologists, who notes the sediment types and out of sight but to the left is the winch-man who makes sure the array does not crash into the sea floor! The sea bed is rather featureless here, an expanse of mud with few animals visible. Too much of this mud was about to appear on deck.

One of the sampling gears is a 3m Beam Trawl, designed to skim over the surface of the sea floor catching the larger "megafauna" including fish. As you can see from the discoloured sea, swollen net and mud on deck it acted more like a dredge than a trawl [5, 6] . The 'mud-larks' (Torjuis, Gjertrude & Anne Helene) get stuck in and are soon satisfied with their work [7] . Cruise leader Lys accounts that none is missing and Geno contemplates having to sort the animals from the mud [8] .

I quite like mud. It usually results in bivalves and I was not disappointed. The large Arctic cockle [9] is the most obvious but most common were, sorry for Latin names, Bathyarca glacialis [10] and Astarte sulcata [11] . Among the other ten, I got two of the species I had come for, over fifty specimens of Mendicula and twenty of Thyasira. You can look at my web site if you want to see more Perhaps the most appealing are these cushion stars [12] while the sponge is positively weird [13] . The cushion stars are apparently the favoured food of the king crab [14] . The giant was introduced into the region from the north Pacific by Russian fishermen who hoped to make their fortunes but it is turning into an environmental disaster as these voracious predators destroy everything in their advance down the coast of Norway.

This happens on research cruises, some vital piece of gear is not working and as usual it has something to do with electronics on the remote camera array CAMPOD. So we are still in Tromsø! [1]

Talking of small cogs [2] in big wheels there was also a problem with one of the winches yesterday, but that is sorted.

A reminder that my ship [3] the "GO Sars" was named after the very famous Norwegian marine biologist who specialised in crustacean and molluscs, his books are still used to this day and are in the Museum's zoology library.

Also in Tromsø are two other research ships the older Norwegian "Hakon Moseby" [4] named after a Norwegian oceanographer and meteorologist and the massive German "Maria S Merian" [5] . This ship was named after Maria Sibylla Merian (1647-1717) a naturalist and illustrator [6 & 7] . See for an account of this gifted lady pioneer who went to Surinam.

The sun is still shining in Tromsø and we have been informed that we sail around 01.00hrs.

Its now 07.30, breakfast time and we are leaving a cloudy Norway behind [8]. If you want to see where we are minute by minute you can see our position on the marinetraffic website

We should be at our first sampling station in 22hrs.

Tromsø University Museum [1] was established in the 1870s, it covers both regional natural history and culture. Small zoology and geology galleries explore northern Norway including an artificial aurora borealis machine (terella) [2]. Zoology is represented by a series of dioramas with a rather familiar sea-bird cliff [3]. There is content on human influences on nature including a view of what the local landscape (including flamingos and parakeets) might look like following climate change [4].

Geology has more content, not surprising with the rugged exposed landscapes up here. I thought the section on building stones was well done with a montage of polished stones [5] and a display of local slates [6]. They are very proud of their 10 metre ichthyosaur from Svalbard. No photo here as the reflection in the glass protection is impossible to resolve. Curator Elsebeth Thomsen tells me that the whole gallery will be refurbished soon with walk-over glass for the ichthyosaur.

Much more challenging was 'Metopa' in the Polarmuseet [7]. This exhibition [8] shows the research work of one of my sea-going colleagues Anne Helene Tanberg seen here on the left at the opening [9]. Metopa is the Latin name of the genus of amphipods that Anne Helene has been studying for a number of years now. The most familiar of the amphipods are the sandhoppers we find on our beaches but Metopa are small cold-water species. In this 28 panel show we are introduced to the morphology, classification and ecology of amphipods and how Anne Helene collects and studies them. For you museologists out there this is a challenging project as the content may not be seen as being for family audience. But Anne Helene has had positive feedback from visitors and school groups including kindergarten. The panels are attractive with excellent photographs of living amphipods [10] as well as reproductions [11] from the classic work of 1894 by the Norwegian Georg Ossian Sars, to whom the research ship has been dedicated. I have included some images of the texts [12, 13, 14], so you can debate among yourselves on the style and content. The panels are supported by a case filled with part of her collection and an epibenthic sledge [15] used to collect amphipods from the ocean floor. Anne Helene has also had workshop days when she has worked in the gallery [16].

Would this work in Cardiff? I don't know. Here people live much closer to nature, most children will have spent some time messing on the shore and the sea is an intimate part of most peoples' lives.