Category Archives: HYPCOP

Unraveling copepod secrets one leg at a time

A blog by HYPCOP

Hyperbenthic copepods (HYPCOP) are a very difficult and diverse group to work with, and identification goes painstakingly slow, because some species can only be distinguished from one another based on small details in some of their tiny legs. As of now, we have no specialists in marine benthic copepods in Norway and our greatest resource is our collaborator Anders Hobæk and the detailed drawings of G.O. Sars from the early 1900s .

Working together under guidance of G.O. Sars and Anders Hobæk

Anders is a senior researcher scientist at the Norwegian Institute for Water Research (NIVA) here in Bergen. He is specialized in copepod taxonomy, but his focus was mostly on freshwater copepods, or marine pelagic copepods. Which makes the marine benthic copepods just a little bit more challenging to work with, however, his skills are transferable and so we get together multiple times a year to work on our collection of benthic copepods to dissect them and identify them.

Beginning of June, we had again one of those get togethers in Flødevigen at the Institute of Marine Research (IMR), where Tone Falkenhaug, the project leader of HYPCOP, is situated. For a week we went through the main clades and groups of species that we had DNA barcodes of but not yet a confirmed species name. A lot of the identification was done with help of the rich and detailed illustrations of G.O. Sars1 published work in 1901 – 03 and 1919 – 21, “An account of Crustacea of Norway”

Detailed copepod drawings from G.O. Sars

Sars dedicated a lifetime of identifying and describing a variety of species and he did not neglect the rich and wonderful group of bottom dwelling copepods. Every species he encountered in those early days he described and drew in detail; he did not leave out the smallest details, that as of now, turn out to be of uttermost importance in determining the species. With small copepods you need a good microscope and fine tools. The first thing to look at is the general shape, is it very dorsally flat, like Peltidium purpureum, or more dimensional like Harpacticus flexus?

Sex is also an important feature; females are often characterized by carrying eggs; one egg sack or two egg sacks can already lead you in the right group. Males have often larger antennule made for holding on to females when mating, and other specialized tools that can be species specific. The little claws, called maxilliped, are they large, small, almost invisible? What about the first pair of legs? The second, third and fourth? The fifth pair of legs is often very characteristic for the species and in certain females, like Thalestris longimana, can be a huge in comparison of the rest of its body.

Thalestris longimana, females of this species has relatively large fifth pair of legs

Our work has a continues workflow consisting of, collecting the copepods, extracting their tissue for DNA barcoding, and keeping the exoskeleton. Once the DNA is successfully sequenced, we can take the exoskeleton and dissect the animal leg by leg to finalize the identification. That way the copepod is identified based on its DNA and morphological features, as this is not always mutually exclusive. DNA can be tricky as you need a good reference library to find the correct species, which is as of now, not complete, or even lacking for many species. Besides, there is such things as DNA contamination, cross contamination between species, therefore you always must look at the morphology to exclude that the DNA gives you the wrong species. Together with images of the animals we are building up a valuable reference library of DNA sequences and a museum collection of dissected animals on fixed slides. This way copepod diversity will continue to be valuable for future generations top study.

Working under the eyes of G.O. Sars

-Cessa


1Sars, G. O. 1901-03. An Account of the Crustacea of Norway. Vol. IV. Copepoda Calanoida.- Bergen Museum, Bergen & Christiana. 171 pp. + 109 plates Sars, G. O. 1919-21. An Account of the Crustacea of Norway. Vol. VII. Copepoda. Supplement. – Bergen Museum, Bergen & Christiana. 121 pp. + 74 plates

Fieldwork for two projects

The projects HypCop (bottom-associated copepods) and Hardbunnsfauna (Invertebrate fauna of marine rocky shallow-water habitats) went on a day-trip to three localities last week.

We made the most of the sunny and calm weather to visit a very exposed site on Sotra, where we collected in the tide pools and on the barnacle-encrusted intertidal.

Afterwards, we went to two marinas, Glesvær and Hjellestad, on a quest for some specific species the projects were in need of.

Back in the lab we set to work documenting the colours of the animals by photographing them alive, as the colours tend to face in fixatives.

It was nice day in the field, and it looks like we found the species we were after!

Follow us on Twitter and Instagram as @PlanetCopepod and @Hardbunnsfauna

– Jon, Cessa & Katrine

 

HYPCOP workshop in Flødevigen

From the 7th to the 11th of March the HYPCOP team once more sat together to work on the identification of the species we have in the collection. The strategy was similar as we had in Bergen last year, but this time we looked focus into specific clades. Besides, we met in Flødevigen this time, instead of Bergen, and visited Tone Falkenhaug at her jobsite with the Norwegian Institute of Marine Research (IMR, Havforskningsinstituttet).

The HYPCOP team in Flødevigen, from ltr; Cessa Rauch (UiB), Jon Kongsrud (UiB), Anders Hobæk (NIWA) & project leader Tone Falkenhaug (IMR).

One way for identifying species of hyperbenthic copepods is by looking at their colors. Unfortunately, these get lost as soon as you fixate the samples in technical ethanol. Therefore, we started the workshop with a short sampling trip just out of the bay in front of the research station. We took a small boat from the research station that had a manual operated hinge on the back of the boat, so we could use that for pulling up the grab.

Preparing the small IMR boat with use of the manual hinge and the grab.

Anders Hobæk operating the grab

One of the advantages of working with tiny animals is that you sometimes only need small gear to collect them. The grab we used is hand size grab, not much bigger than a 10L basket.

However, as it is made entirely out of metal it is still heavy, which ensures it will be able to “grab” the mud from the bottom when it hits the sea floor.

Once we arrived at a nice location with the boat, we placed the grab over the edge of the boat and let it sink to the bottom which was about 40m deep.

Once the grab would touchdown it would close and engulf softbottom material including the animals that are associated with it. The closed grab would be town back with the manual hinge from the boat. Once onboard, we would empty the grabs content in a bucket and sieve some of the material. This material would go back to the lab for examination.

We carefully examined the sediment, and it was not yet very rich with benthos. We caught a few interesting copepods species, that we documented and fixated for identification.

One of the species we caught with the grab

March is not the best season for benthic copepod sampling, the water is still very cold from the winter and most of the small algae needs to grow back. Benthic copepods are much more abundant with rising temperatures and lots of algae growth. Back in the laboratory we started working on our museum collection copepods and assigned clades in our family tree that we would examine first.

Tone Folkenhaug (left) and Anders Hobæk (right) concentrated with dissecting copepods.

Bigger clades had more priority, and so we took those samples and checked the individual specimens. All the specimens we had in our collection are exoskeleton remnants from the DNA extraction (hence we could have a phylogenetic tree). The exoskeletons are still good for morphology identification but hard to see (due to there translucent nature). Therefore, to help with the identification we would often stain the exoskeletons either with lactophyl blue or lignin pink, which resulted in a visually pleasing collection of prepared slides of different colors.

Slides of Lactophyl and lignin pink stained copepods

Thanks to the workshop we now have manage to identify 145 out the 580 specimens; our efforts for identifying will continue and a new workshop is already planned, we meet again in June and in September, with also this time, help of international researchers!

Stay tuned with @planetcopepod!

-Cessa

Legendary colleagues meet once again; in search of Idzi Drzycimskis harpacticoids with help of R/V Hans Brattström

R/V Hans Brattström. Photo: Anne Helene Tandberg

Professor Dr. Idzi Drzycimski was one of the few who studied copepods here in Bergen, and in particularly the order of Harpacticoida. Drzycimski was foremost an occupied oceanologist and ichthyologist (the study of fish), but during his career he also described several new species from the order Harpacticoida. A few of those records are from Norway and are currently an important resource for our study of hyberbenthic copepods (HYPCOP). Drzycimski stayed in Bergen for a few years during the sixties and build up an extensive collection of copepods.  

 

Idzi Drzycimski 

Idzi Drzycimski was born December 5th, 1933 in Klonowo; a very small village North of Bydgoszcz, Poland. He studied Biology with a specialization in Hydrobiology at the Odessa University of I.I. Miecznikow. In 1957 he graduated and started working at the Sea fisheries Institute in Gdynia at the Oceanography Department, led by Professor Kazimierz Demel. Later followed by a career at the Department of Oceanography and Marine Biology at the University of Agriculture in Olsztyn, Faculty of Fisheries. In 1963 he obtained the degree of Doctor in natural sciences and in 1969 he habilitated. In 1985 he received the academic title of associate professor and eventually became full professor in the same year.

Drzycimski publication in Sarsia about new species of copepods.

Throughout his career he completed several internships in Germany, Norway, Italy and participated in several research cruises in the South Baltic Sea, North Sea and the Norwegian Fjords. During these cruises he collected and described 11 species new to science and 3 new types of marine crustaceans that have entered into the international zoological systematics. He promoted 8 doctors and continued to be the head of the department of oceanography at the faculty of sea fisheries. All while he published hundreds of articles and finally in 2001 he was awarded the Medal of Professor Kazimierz Demel.

 

 

Sampling for copepods 

As noted earlier, HYPCOP uses Drzycimski works for the project; his database, collection and publications from his years in Bergen are good source of information. Drzycimski published two publications with Harpacticoida findings from 1967 and 1968. He described 5 new species of Harpactcoida from West Norway, with sampling locations close to Bergen. Now, half a century later, we wanted to revisit these sampling sites to see if we could find the same or different species. Some off the sampling locations were from the middle of the fjords near Bergen and would therefore be excellent to revisit.  Drzycimski had sampled different spots from around the Krossfjorden, Bjørnefjorden and Raunefjorden. Most of these were deep sandy and muddy bottoms, from around 300-700m. Species that he had found there he described as Marsteinia typica, Pseudotachidius vikingus, Marsteinia similis, Leptopsyllus elongatus and Dorsiceratus octocornis. These all have the typical small body sizes of around 400-800 μm and are very inconspicuous and hard to find with the naked eye.  

 

Brattström & Drzycimski 

 

Beautiful day for sampling benthos. Photo: Cessa Rauch

With help of research vessel Hand Brattström and researcher Anne Helene Tandberg, we managed to sample two locations in the Krossfjorden between 400-700m depth that were sampled before in the 60s by Drzycimski. Prior to the sampling day we made a hit list of 4 locations that we wanted to revisit, but two of those locations got inaccessible. In the span of 60 years a lot of things have changed, places that once where easy accessible for sampling are nowadays littered with e.g. fishing gear waste. Which would destroy our plankton nets when they get stuck in this. On top off that Drzycimski also did not describe in his papers how he managed to collect his copepod samples, but most likely this was done with a sled, and in this case we would be using the R.P. sled. The R.P. sled is an epibenthic sampler. That means that it samples the

Anne Helene Tandberg and crew working on retrieving samples from the RP-sled. Photo: Ellen Viste

animals that live just at the top of the (soft) seafloor with a fine plankton net, if you want to read more details about the R.P. sled you can read that here. Once again our sled expert Anne Helene would join us on this trip to help HYPCOP with sampling and also to be on the lookout for sampling for amphipods. After the sled collected the benthic animals, we needed to filter the sled sample by a process which is called decanting (See the YouTube movie in this blog).  With decanting you separate the mixture of the animal soup from the liquid by washing them in a big bucket, throw the liquid through a filter and collect the animals carefully to avoid damaging them.  

 

 

 

 

Drzycimskis visit at the museum was during the years of Hans Brattströms Professorship at the University of Bergen in marine biology (1962-1978). During those years Brattström started the scientific journal Sarsia, where Drzycimski published his copepod species description’s. There is not much about whether the two professors knew each other well, but it is very likely. And so it was special that few generations later, Hans Brattström once again facilitates research for Drzycimski, although this time as a research vessel and a new generation of scientists working on marine benthos.  

New generation of scientists working on marine benthos. from the left: Anne Helene Tandberg, Francisca Carvalho, Cessa Rauch, Ellen Viste and Justine Siegwald

Cessa & Anne Helene 


Literature:

Drzycimski, I. “Zvvei neue Harpacticoida (Copepoda) aus dem Westnorwegischen Kdstengebiet.” Sarsia 30.1 (1967): 75-82. 

Drzycimski, I. “Drei neue Harpacticoida aus westnorwegen.” Sarsia 36.1 (1968): 55-64. 

Throwback Thursday; HYPCOP workshop at the museum

The project of studying hyperbenthic copepods (HYPCOP) is unique in multiple ways; we study a very unknown group of marine copepod species with very little taxonomic knowledge available here, in Norway. It is challenging as there are more than 700 species described, and possibly more. With pandemic lockdowns, it was hard to have international specialists come and help us, so we had to rely on resources available locally. With so many institutes involved from different corners of Norway, it was not always easy to meet up physically to work on our collection. Hence, when it happens, it is a memorable event, and valuable progress for the project is made.

One of the many species of copepod we have here in the collection at the UiB museum

We have Tone Falkenhaug as the project leader, situated at the Institute of Marine Research in Flødevigen (IMR), than we have our collaborator from Norwegian Institute for Water Research (NIVA), Anders Hobæk and the three technicians at the department of natural history from the University of Bergen. The year before we all got together in Flødevigen, so for 2021 we decided that it would be Bergen to have another workshop.

From ltr; Anders Hobæk, Cessa Rauch, Tone Falkenhaug and Francisca Carvalho making the picture

A year into our project we managed to build up a substantial collection of benthic copepods; currently we have around 460 registered specimens, and 195 off those are barcoded with two different DNA markers, mitochondrial (COI) and ribosomal (16S). What keeps ahead of us is the monster task of working through our specimens to label the DNA barcodes with morphological identifications. It means many hours of very precise work with the finest needles, while sitting at the microscope.

During our workshop in Bergen we got together to work through one of the copepod family trees we generated from their DNA:

Preliminary tree of the COI mitochondrial marker

Anders Hobæk is a taxonomist with many years of experience dissecting copepods, and together we went through the samples one by one. It is very satisfying to be able to identify a specimen and get the to the same species level as the DNA barcode. There are multiple reasons as why we choose to identify species based on morphology.

Not all species are easy to barcode, as copepods, especially the benthic ones, are often so extremely tiny; it is difficult to get good quality DNA extracted from them.

Copepods are tiny; this one with scalebar

The small quantities of copepod DNA goes hand in hand with greater risk of contamination of other surrounding DNA, especially if you work with more general markers. Besides, even if we have the DNA barcode, not all copepod DNA is identified as such, which means that even with the right DNA, when running it through the database, it tells us that we have fly DNA, to give an example. Last but not least, in a lot of cases, we were not able to get good DNA sequences from the copepod extracts, so the only option is identifying them morphologically, by dissecting the animals and with help of literature identify the right genus, or even better, the species.

Species identification with help of literature, here a page from G.O. Sars

Our next workshop shall take place again in Flødevigen, in the meantime we keep you updated about our planet of the copepods.

Follow us for more copepod content @planetcopepod, see you there!

 

-Cessa

Sampling together in the Sognefjord

From 09 to 13th of May different artsdatabanken projects within the Natural history museum joined efforts during a fieldwork trip to Hjartholm located at the Sognefjord.

The Sognefjord is an interesting fjord for sampling as it is the largest and deepest fjord in Norway and the second largest in the world! This often results in some unique fauna, especially at greater depths. Therefore HYPCOP (Hyper benthic copepods), NORHYDRO (Norwegian Hydrozoa), AnDeepNor (Annelids from the Deep Norwegian Waters) and Hardbunnsfauna (rocky shore invertebrates) travelled toward the small town Hjartholm were we set up laboratory and living space for sampling and processing fresh material.

Hjartholm is located towards the exit of the Sognefjord. From here we would do shallow and deep sampling with help of Research Vessel Hans Brattstrøm

Team members from different projects, Norhydro, HYPCOP, hardbunnsfauna and AndeepNor in front of the boathouse that was transformed into a lab for the occasion

Boathouse communal area turned into a temporary lab

AnDeepNor was on the quest of collecting marine bristle worms (annelida) from the deepest part of the Sognefjord, about 1000m deep.

AnDeepNor researchers from ltr; Miguel Angel Mecca, Tom Alvestad, Nataliya Budaeva, Jon Kongsrud

Jon Kongsrud with the grab

This would be done with the help of research vessel Hans Brattstrøm and a so-called grab. A grab is a device that looks like a clamshell made out of heavy metal. It would be dropped in the water open, and once touching the bottom it would close and grab soft bottom sample.

Unfortunately, on the first day some important machinery for collecting deep samples broke after the third grab. And therefore, AnDeepNor was stuck with only 3 samples for the remaining of the fieldwork days. The good news however is that they did find a great diversity of worms in the only 3 grab samples they found.

 

Project leader Nataliya with in her hand a plate with clipped tissues from her worms

Once the worms were sorted, preliminary identified and catalogued small tissue was clipped of 96 specimens for barcoding at the University of Bergen DNA laboratory.

All the results of this will be publicly available at the end of the AnDeepNor project in October this year. We are looking forward to their results!

 

 

 

 

NorHydro has been working hard on collecting hydrozoan samples from different localities in Norway.

NorHydro researchers from ltr Luis Martell and Joan Soto Angel

This time they were more than happy to join the possibility of getting some seriously deep samples from the Sognefjord. With their plankton net they went sampling up to 1200m, which resulted in some beautiful specimens

Left: Margelopsis hartlaubii, right: juvenile Melicertum octocostatum

They also took the opportunity to collect some shallow-water benthic hydroids, just in front of the lab where there was a small dock for boats. In the lab they set up a photo-studio to make some beautiful macro images of their collected specimens for everyone to enjoy.

Left: Laomedea flexuosa; top right: Bougainvillia muscus; bottom right: Eudendrium sp.

HYPCOP (Picture 9. Team HYPCOP with ltr Francisca Carvahlo, Cessa Rauch and Jon Kongsrud) focus this time was mainly shallow water around the Sognefjord by snorkelling (picture 10. Sampling for Hardbunnsfauna and HYPCOP by means of snorkelling), we sampled from 4 different stations and as you can guess, there were copepods in all of them.

Team HYPCOP with ltr Francisca Carvahlo, Cessa Rauch and Jon Kongsrud

Sampling for Hardbunnsfauna and HYPCOP by means of snorkelling

However, some locations had definitively more diversity than others, this mostly had to do with the site being more exposed, or whether there was a lot of freshwater run-off from land that would influence the sites salinity. The fresh collected copepods were photographed and are now ready to be prepared for barcoding in order to determine the species. And although small, they can be very beautiful as well, just not always easy to photograph such active critters.

Even though we had to deal with some gear equipment failure, we still managed to have a very productive week of sampling, in which all the participating projects got their hands-on valuable specimens from the amazing Sognefjord!

Interested to follow up with these projects? You can find us across all social media platforms (Twitter, Instagram and Facebook @hardbunnsfauna, @planetcopepod #NorHydro #AnDeepNor), see you there!

-Cessa, Nataliya & Joan

Sun is out, scientists are out!

 

Staff engineer Lina Ljungfeldt with the Bladderwrack algae Fucus vesiculoses in Glesvær, Norway. Photo Bjarte Kileng

With few good weather windows here in the West coast we need to take the opportunity for collecting when it arises. Tuesday afternoon (27.04)  we took our chance to sample in Glesvær for some fresh copepods and Bladderwrack (Fucus vesiculoses) for researchers from the University of Trier.

The team consisted of staff engineer Lina Ljungfeldt, PhD student Justine Siegwald, Citizen scientists Bjarte Kileng and head engineer Cessa Rauch.

The Tuesday afternoon sampling team from ltr Lina Ljungfeldt, Cessa Rauch and Justine Siegwald. Photo BK

Picture of the photographer himself, citizen scientist Bjarte Kileng joining the expedition team. Photo Justine Siegwald

We chose Glesvær because we needed easy access to the shore with rockpools and lots of algae. Researchers from the University of Trier (Germany) are collecting Fucus vesiculoses from different parts in the world to study the community of animals and bacteria that are associated with the algae. We were happy to help out while also collecting fresh copepods for HYPCOP (@planetcopepod).

We needed 20 individual algae pieces that needed to be cut from the substrate and any epifauna big enough to the naked eye had to be removed.

Justine Siegwald picking out individual Fucus vesiculoses algae from the rocky shore. Photo BK

After collecting the algae in the green baskets we needed to rinse the algae and put them in bags afterwards. The algae were transported back to the museum on ice and stored in the freezer waiting for their final journey to Germany.

Cessa Rauch rinsing the algae, dry suit came in good use! Photo JS

HYPCOP member Cessa Rauch went along and collected some copepods from the beautiful rockpools.

Cessa collecting copepods from the rockpools in Glesvær. Photo BK

Rockpools are great source for easy benthic copepod collecting. When low tide leaves the rockpools exposed, many small marine organisms stay ‘trapped’ in the cracks of the rocky shores. Just sampling some small algae and the water itself contains many benthic organisms like our copepods. The copepods, along with the algae, were taken back to the museum and sorted based on their morphotype. These fresh specimens will later be used for DNA extraction and barcoding.

If you wish to see how beautiful benthic copepods are than don’t forget to follow @planetcopepod on Twitter https://twitter.com/planetcopepod and Instagram https://www.instagram.com/planetcopepod/ or become a member of or Facebook group, for the latest updates! https://www.facebook.com/groups/planetcopepod

-Cessa

 

 

Copepod girls!

Copepod girls; Cessa Rauch (left) and Francisca Carvalho (right) working on copepods, photo Katrine Kongshavn).

International Woman’s Day was on 8th of March and this coincided this year with the start of a great fieldwork trip with an (almost) girl only expedition team!

Multiple research projects headed towards Espegrend Marine Biological field station in Bergen, to spend the week collecting and sorting specimens. The group consisted of representatives of Hardbunnsfauna (rocky shore invertebrates @hardbunnsfauna), Norchitons (Norwegian chitons @norchitons) and HYPCOP (copepods @planetcopepod).

From ltr; HYPCOP (Cessa Rauch), Norchitons (Nina Mikkelsen), HYPCOP (Francisca Carvalho), Hardbunnsfauna (Katrine Kongshavn). Photo: Jon Kongsrud

The plan for the week was to have access to the research vessel Hans Brattström while also working from the field station on the mainland. This would give us very good opportunities for reaching different sampling habitats. But as always with fieldwork expect the unexpected; unfortunately, after day 1, our R/V Hans Brattström got motor problems, so the planned dredge sampling did not happen. It is good to be creative in those situations because we still managed to get a lot of sampling done by collecting at the piers where the research vessel was docked and in front of the research station itself.

View from the research station in Espegrend, photo Cessa Rauch.

Sampling from the pier in front of the research station, photo Francisca Carvalho

On one of the days (when the sun was out!) we took the small research boat from the field station to explore the habitats of the nearby islands and do some shallow sampling there.

Out sampling with the small boat, photo Cessa Rauch

Once we arrived at the island of Søre Egdholmen we needed to dock the small boat without a pier; rest assure this gave interesting scenarios with being half in the water while the rest of the team and the equipment was in the boat.

Docking the small boat without a pier, photo by F. Carvalho

Once on the island we started to collect lots of material; for copepods, especially shallow benthic ones, that is quite a simple task. The best way is to use a fine meshed net, like a plankton net, and grab a lot of substrate like algae, some sand and small gravel. A lot of species basically stick to the substrate and with the plankton net have no way to escape. By keeping the plankton net with substrate in a bucket with seawater the samples stay fresh the longest.  Back to the marine biological station we kept the freshly collected samples in tanks with good saltwater circulation (which the station has access to in the laboratories).

Well let me tell you, we had such nice samples off copepods, not only just the quantity (because with copepods that is never a real issue), but very diverse too.

A drop of copepods, rich diversity from Espegrend. Photo: Cessa Rauch

Every single morphotype was being documented while they were still alive to keep the colors intact.

Overview of the different morphotypes we collected

And then numbered, labeled and fixated in ethanol for the collection.

Copepod collection

The goal for HYPCOP this week was to collect and register fresh copepod samples for DNA barcoding.

Back in Bergen we brought our copepods to the laboratory for DNA barcoding.

Their DNA is, as we speak, on their way to the sequencing center in Canada to become part of the Barcode of Life Data System that eventually everyone will have access to. Curious to see what this platform is all about, check out http://www.barcodinglife.org.

Until next time! Don’t forget to follow @planetcopepod on Twitter https://twitter.com/planetcopepod and Instagram https://www.instagram.com/planetcopepod/ or become a member of or Facebook group, see you there! https://www.facebook.com/groups/planetcopepod

-Cessa & Francisca

 

 

 

Sled test for copepods

R.P. sled onboard R/V. H. Brattström

Happy new year to everyone! We managed to start 2021 with a day at sea, testing the R.P. sled for collecting benthic copepods from greater depths . January 27 we went out with research vessel Hans Brattström, crew and research scientist Anne Helene Tandberg who also turns out to be a true sled expert! She would join HYPCOP to teach how to process the samples from the R.P. sled on the boat.

 

 

 

 

Anne Helene Tandberg (left) joining HYPCOP (Cessa Rauch right) for teaching how to use the sled.

But first, what is an R.P. sled and why is it such an important key in the collection of copepods? The R.P. sled is an epibenthic sampler. That means that it samples the epibenthic animals – the animals that live just at the top of the (soft) seafloor – and a majority of these are often small crustaceans. The “R.P.” in the name stands for Rothlisherg and Pearcy who invented the sled. They needed to collect the juveniles of species of pandalid shrimp that live on the sea bottom floor. These animals are very small so a plankton net was necessary to collect them; a ‘normal’ dredge would not quite cut the job. They needed a plankton net that could be dragged over the bottom without damaging the net or the samples and also would not accidently sample the water column (pelagic); and so, the R.P. sled was born. This sled was able to go deeper than 150m, sample more than 500m3 at the time and open and close on command which was a novelty in comparison to the other sleds that where used in those days (1977). The sled consists of a steel sled like frame that contains a box that has attached to it a plankton net with an opening and closing device. The sled is heavy, ca. 150kg, and therefore limits the vessel sizes that can operate it; the trawl needs to be appropriately equipped including knowledgeable crew. It is pulled behind the vessel at slow speed to make sure the animals are not damaged and to make sure it does not become too full of sediment that is whirled up.

 

 

Sieved animals from the decanting process

So off we went with r/v Hans Brattström pulling the heavy gear at ca. 700m depth with 1 knot and a bottom time of 10 minutes sampling the Krossfjorden close to Bergen. It was a beautiful day for it with plenty of sun and calm seas. The crew handled most of the sled, leaving sorting the samples up to HYPCOP under the guidance of Anne Helene. Which is not as straight forward as it may sound! The process of filtering the samples after collecting them from the sled is done by decanting, which you can see in this movie from an this blog (in Norwegian) from earlier.

Decanting set-up for R.P. sled samples

Decanting means separating the mixture of the animal soup from the liquid by washing them in a big bucket, throw the liquid through a filter and collect the animals.

Sieved animals from the decanting process

This all needs to be done with care as the animals are often very small and fragile. After collecting, the most time-efficient and best preservation for the samples is to fixate them immediately with ethanol, so they don’t go bad while traveling back to the museum.

Fixating collected animals with technical ethanol

For collecting copepods we use a variety of methods; from snorkeling, to scoping up water and plankton nets, but for greater depths and great quality benthic samples the R.P. sled will be the most important method. We thank Anne Helene for her wisdom and enthusiasm that day for showing HYPCOP how to work with such interesting sampling method

 

We got some nice samples that will be sequenced very soon so we can label them appropriately. Although this first fieldwork trip off the year was mainly a teaching opportunity, we still managed to sample two stations with plenty of copepods and lots of other nice epibenthic crustacea, and Anne Helene is especially happy with all the amphipods she collected during the day. So for both of the scientists aboard this was a wonderful day – sunshine and lovely samples to bring back to the lab!

Some fresh copepods caught with the R.P. sled

– Cessa & Anne Helene


Follow HYPCOP @planetcopepod Instagram, for pretty copepod pictures https://www.instagram.com/planetcopepod/

Twitter, for copepod science news https://twitter.com/planetcopepod

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See you there!

Brattström baby, HYPCOP goes offshore!

Last days of November HYPCOP spend two days (26th & 27th) offshore. We had the possibility to join some sampling efforts of NorHydro and others on the research vessel Hans Brattström.

Research Vessel Hans Brattström ready early in the morning, photo Cessa Rauch

This vessel is owned by the University of Bergen and operated by the institute of Marine Research (IMR, Havforskningsinstituttet).

H. Brattström is used 200 – 230 days a year along the West coast of Norway. It has the capability of operating different sampling gear, which makes it useful for multiple projects, studying a variety of marine organisms, from fish, to worms, jellyfish, and yes, also copepods!

On the first day HYPCOP joined NorHydro consisting of Luis Martell (UiB) and Joan Soto Angel (Sars):

NorHydro team and HYPCOP; from ltr Cessa Rauch, Luis Martell and Joan Soto Angel, photo Cessa Rauch

Plankton net being lowered in the ocean with some early morning sun, photo Cessa Rauch

 

 

The main sampling gear consisted of a large plankton net that was slowly dropped to 660m, 245m and 128m depth.  We sampled close to Bergen in Raunefjord, Krossfjord and Fanafjord.

Sampling for jellyfish needs to be done with caution, with the net going up to fast, the animals will just fall apart because of the pressure. So, a depth of 660m can take up to an hour and more before we could see the results.

 

 

Joan Angel Soto scanning the shore for birds, photo Cessa Rauch

During the waiting times we didn’t let our time go to waist, with binoculars we scanned the air and shore for birds.

After waiting for some time, the plankton net was brought back on board and contained, besides jellyfish and other pelagic planktonic dwellers, many million copepods. Mostly consisting of a few species. One of the species had a distinguishable blue egg sack, this is Paraeuchaeta norvegica (Boeck, 1872). This species is an active predator that feeds on other (smaller) copepods by rapidly jumping on them and catching their prey with their large maxillipeds (mouthparts).

 

 

The second day HYPCOP joined head engineer Bjørn Reidar Olsson (UiB) and PhD student Miguel Meca (UiB)

HYPCOP (Cessa Rauch left) joining Miguel Meca (middle) and Bjørn Olsson (right), photo Cessa Rauch

They were looking for shark teeth and polychaetes (marine worms) respectively and used the grab, which is perfect for benthic copepod sampling. The grab is basically a big metal clamshell that collects sediment from the seafloor. Working with grab samples gets dirty very quickly, you have to wash through the sediment to find your animals.

The grab with Cessa Rauch (HYPCOP left), Miguel Meca (middle) plus operator Bjørn Frode Grønevik (right), photo Bjørn R. Olsson

Most of the sediment was filtered out in order to find our copepod friends. Although less plentiful in comparison to the plankton net sampling the previous day, we still found some copepods hiding in the dirt. At moment of this writing, the the copepod species we collected have not be named yet, however, the last months we have been experimenting with barcoding the first batch of 60 different specimens. We had a 43% success rate. Usually, marine invertebrates have a success rate between 40 – 70%, so it was still within the margin, but not with a lot of enthusiasm. HYPCOP will spend the remainder of 2020 and the beginning of 2021 in the laboratory figuring out what the culprit of this low success rate could be.

For HYPCOP this will be the last blog before the Christmas holidays and the New Year. Therefore, we want to take the opportunity to wish you happy holidays and hope to see you around in 2021 with from us more copepod news to share!

-Cessa


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