Category Archives: Field work

Some hydroids, four naturalists, and a small island in the North Sea

NorHydro partner (and hydrozoan expert) Joan J. Soto Àngel from the Sars International Centre for Marine Molecular Biology went in a sampling trip to Kinn to collect benthic hydroids. Here is an account of his experience in this trip:

Kinn is a small grassy island on the western Norwegian coast. Today it is a quiet, peaceful place with only a few inhabitants, but in the past it was an important fishing town and the center of the cultural and religious life of the area, as evidenced by its imposing medieval stone church (Kinnakyrkja). The island is also a place of historical relevance for biologists, since it is intimately tied to the life and discoveries of one of the most prominent naturalists of the XIX century, Michael Sars, who worked as a priest in Kinnakyrkja for many years.

Here I am, ready to sample! The island behind is Kinn, easy to recognize thanks to its characteristic cleft silhouette. Picture: Cessa Rauch

The islands in the area face the ocean and are rather exposed, so the vegetation is not particularly tall, but the waters are teeming with life. Picture: Joan J. Soto

The XIX century Norwegian naturalist Michael Sars. Picture from Wikicommons (public domain)

Sars described many species inhabiting the waters around Kinn and also made key observations about their distribution and life cycle. Indeed, he was the first to discover that jellyfish and polyps are in fact different stages of the same animals!

This finding led him to be recognized as an outstanding zoologist of his time. Even now, ca 200 years after, his extensive work is regularly consulted by researchers of many fields. Like me and the other participants of the Artsdatabanken project NorHydro, Sars was fascinated by the group we call Hydrozoa, which is why it was very interesting for our project to join a sampling trip of the University Museum of Bergen in the same waters where he sampled and described many hydroids, hydromedusae and siphonophores.

Because Sars was also interested in other critters of the sea besides hydrozoans, it was only natural to make this sampling trip a joint, collaborative effort. In our case, three marine scientists were involved, each representing a different project: I was in charge of the hydrozoans for NorHydro, while Anne Helene Solberg Tandberg focused on amphipods (NorAmph2) and Cessa Rauch concentrated on sea slugs (Sea Slugs of Southern Norway). But we did not limit ourselves to our favorite animal groups; we also sampled some poychaetes, bryozoans, ascidians and echinoderms for two other projects based at UMB, Hardbunnsfauna and AnDeepNor. In addition, while we sampled extensively the waters around Kinn, we also stopped in the way to the island and back and collected some animals in two other localities in the coast of Sogn og Fjordane. Our efforts paid off and, despite some windy weather, we came home with many specimens to analyze and samples to sort.

Three more contemporary naturalists working for different projects: Joan (left, NorHydro), Cessa (middle, Sea Slugs of Southern Norway), and Anne Helene (right, NorAmph2). Picture: Joan J. Soto

For the hydrozoans, the majority of samples consisted in colonies of hydroids belonging to the families Sertulariidae, Haleciidae and Campanulariidae. This was not surprising as Sertulariidae (sensu lato) is the largest and most diverse family in all Hydrozoa, and their conspicuous colonies are relatively easy to recognize and collect. The haleciids are represented in Norway mainly by species of Halecium, whose colonies are among the largest benthic hydrozoans of the country. As for the campanulariids, particularly those belonging to genera Obelia, Laomedea and Clytia, they are common inhabitants of rocky and mixed bottoms all around the world, and are especially conspicuous when growing on macroalgae such as kelp. To correctly identify some of these specimens, we will look closely at their morphological characteristics and will also employ molecular techniques of DNA analysis. Hopefully this approach will help us understand the diversity of benthic hydroids living around Kinn, and will allow us to determine whether the species that we encountered are the same that Sars studied.

Dynamena pumila was one of the most conspicuous species of hydroid that we collected in this trip. It belongs to the speciose family Sertulariidae.

We were very lucky to have the help of the crew of RV Hans Brattström. This is how the command center of the boat looks like!

You’ll find the results of these and other NorHydro’s analyses here in the blog as we progress, and more updates on the project can be found on the Hydrozoan Science facebook page and in Twitter with the hashtag #NorHydro.

– Joan


References and related literature about Michael Sars

Tandberg AHS, L Martell (2018) En uimodstaaelig lyst til naturens studium. Yearbook of the University Museum of Bergen: 17 – 26.

Sars M (1835) Beskrivelser og Iagttagelser over nogle mærkelige eller nye i Havet ved den Bergenske Kyst levende Dyr af polypernes, acalephernes, radiaternes, annelidernes, og molluskernes classer. Thorstein Hallagers forlag, Bergen.

Windsor MP (1976) Starfish, jellyfish and the order of life. Issues in Nineteenth-Century Science. Yale University Press, New Haven. 228 pp

NorHydro goes back to school

To the Research School in Biosystematics (ForBio), that is!

Last April, NorHydro participated in two events organized by ForBio (who is actually one of the partners of our project): the 2019 Annual ForBio Meeting and the ForBio and MEDUSA course “Zooplankton Communities – Taxonomy and Methods”. Both events were very productive and fun, here is the story:

The 2019 Annual ForBio Meeting was held in Trondheim. Many high-quality talks were delivered during this meeting and NorHydro received useful feedback from students and consolidated scientists from all the Nordic countries. It was particularly important for NorHydro to be present at the annual meeting, because together with ForBio we are planning a course on hydrozoan diversity and phylogeny in 2020, so the meeting in Trondheim was the perfect vehicle to advertise both the course and the activities and expected outcomes of the project.

I did not see any hydroid in Trondheim during the meeting, but the trees in the city center looked suspiciously like colonies of Obelia dichotoma. Pictures: Luis Martell

In addition to NorHydro, the University Museum of Bergen attended the meeting with interesting talks from some of our PhD students and guests, presenting diverse subjects as the phylogeny of the plant genus Potentilla (by Nannie Persson), morphological data of the polychaete family Lumbrineridae (by Polina Borisova), and the diversity of the marine snail genus Scaphander (by Justine Siegwald).

Snapshots of two of the UMB talks during the annual meeting: Luis presenting NorHydro (left) and Justine explaining the mysteries of Scaphander (right). Pictures: Nannie Persson

Later in the month, Aino, Joan and I participated as teachers in the course “Zooplankton Communities – Taxonomy and Methods”, an event organized by ForBio in collaboration with the DIKU-funded project MEDUSA. The course was packed with motivated students and beautiful specimens of gelatinous zooplankton, and we managed to collect some hydromedusae for NorHydro as well. The bloom of hydrozoans is more evident in the water column than anywhere else, since the reproductive season is in close relation with the increasing abundance of food items in the plankton (which in turn follows the spring bloom of microalgae), and our samples confirmed that spring is the perfect hydrozoan hunting season. Beautiful sunsets, friendly chats, and exciting lectures complemented the activities of the zooplankton course, making for a great month in the partnership of ForBio and NorHydro!

We caught some interesting jellies during the course, like these Leuckartiara octona (left), Tima bairdii (middle), and Halopsis ocellata (right). Pictures: Elena Degtyareva

Happy participants of the zooplankton course. From left to right: Raphaelle Descoteaux, Christina Jönander, Ksenia Kosobokova, Elena Temereva, Kyle Mayers, Luis Martell, Elena Degtyareva, Aino Hosia, Sanna Majaneva, Ksenia Smirnova, Ekaterina Nikitenko, Anna Shapkina. Joan Soto (right picture) explained how to keep ctenophores alive during the visit to the Ctenophore Facility of the Sars Centre. Pictures: Nataliya Budaeva, Luis Martell

– Luis

Travelouge from the Hardbunnsfauna-project: On a quest for samples

Tide pools and kelp forests in Lofoten (Photo: K. Kongshavn)

In late April Endre, Jon, Katrine and Tom set out from Bergen for what would turn out  to be a rather epic road trip (we ended at 4380 km..!) aiming to collect material for our project on Invertebrate fauna of marine rocky shallow-water habitats: species mapping and DNA barcoding (Hardbunnfauna), the other ongoing Artsprojects, and for the museum collections in general. We had little to no shallow water material in the collections from the region we targeted:

Dark dots are where we have museum material from (though it may be treated in such a a way that it is (no longer) suited for genetic work), and the pink stars are where we collected now (map by K. Kongshavn)

Details of our sampling – we used a variety of gear to collect material, and set up lab where we were staying to process the samples. (Graphic: K. Kongshavn)

Sampling in various habitats using different kinds of gear

The samples were processed (sorted and photographed) at our homes away from home; we managed to rig up quite serviceable lab spaces for ourselves in each spot.

One of the things we were after was kelp stems – or rather, the animals living associated with them

A part of our catch!

A closer look at some of what we found: Hydrozoa and Bryozoa, various crustaceans (pictured are two Mysida, an Isopod and an Amphipod), Nudibranchs and other Gastropods, Polyplacophorana, Ascidians, a Platyheminth and various Cnidaria. 

It was a highly successful – and very lovely! – field trip, and the samples collected will benefit a multitude of ongoing and future research.

Follow us on social media for frequent updates, we are at Instagram and Twitter,  as @hardbunnsfauna

-Endre, Jon, Tom & Katrine

 

Spring time is hydrozoan time

Spring means warmer temperatures, increasing daylight, flowers blooming everywhere… and a lot of outdoor and outreach activities for our projects at the Invertebrate Collections of the museum! In particular, project NorHydro started last month with a kick-off workshop (read more about it here) and we have not stopped collecting specimens, attending conferences, teaching courses and joining sampling trips since then. But why is it that spring is such an important time for hydrozoans and NorHydro?

Well, for starters, spring is the reproductive season for many species of hydrozoans in Norwegian waters. Most Norwegian hydrozoans are seasonal animals and for many of them the increasing temperatures and daylight of March and April trigger a shift in the life cycle towards the production of reproductive stages.

Tiny hydromedusae were already being produced in many of the hydroids we collected, like these colonies of Sarsia tubulosa (left) and Obelia dichotoma (right). Pictures: Luis Martell

Colonies of Eudendrium vaginatum (left), Kirchenpaueria pinnata (middle), and Halecium halecinum (right). Photos: Luis Martell and Joan J. Soto Àngel

The reproductive stages are often necessary to correctly identify a hydroid colony to species level, so we took advantage of the season to collect the very first samples of the project during the kick-off workshop. More than 50 samples of hydrozoans were collected thanks to the efforts of all the participants, and special thanks are due to NorHydro’s team of hydrozoan experts for identifying the specimens and making for a great start of the project.

The hydrozoan team: Aino (left), Peter (in both pictures), and Joan (right), hanging around in the lab of the Marine Biological Station during the kick-off workshop. Pictures: Luis Martell

Peter Schuchert from the Natural History Museum of Geneva was a very special participant in this meeting, where he kindly shared his extensive expertise with us. Peter’s knowledge of hydrozoans is impressive, and it was a real pleasure to learn from him on everything from collecting methods to preservation techniques and species identities. Completing our team of experts were our very own Aino Hosia from the University Museum, who stopped by to share some of her experiences on hydrozoan diversity in the region, and Joan J. Soto Àngel from the Sars International Centre for Marine Molecular Biology, who collected many specimens and participated in several interesting discussions about the expected outcomes and potential subprojects of NorHydro.

Our samples were full of hydroids, most of which were documented and preserved for future DNA work. Pictures: Luis Martell and Joan J. Soto Àngel

Of course one of the great advantages for NorHydro during the workshop was the possibility to learn from the activities and results of our sister projects Sea Slugs of Southern Norway and Hardbunnfauna, and to share experiences with them and with the members of the university’s student dive club (SUB-BSI). With such amazing partners and professional collaborators, it was impossible for the kick-off workshop not to be a big success, so thank you all for giving NorHydro the best possible start!

We had all types of weather during the workshop, going from almost-summer to snowy-winter in the same day! Pictures: Luis Martell

Keep up with NorHydro here on the blog, as well as in the Facebook page of Hydrozoan Science  and in Twitter with the hashtag #NorHydro.

Luis

Workshop week at Espegrend field station

The final week of March was teeming with activity, as no less than three Norwegian Taxonomy Projects (Artsprosjekt) from the Invertebrate Collections arranged a workshop and fieldwork in the University of Bergen’s Marine biological field station in Espegrend.

The projects – Sea Slugs of Southern Norway(SSoSN), Norwegian Hydrozoa (NorHydro) and Invertebrate fauna of marine rocky shallow-water habitats: species mapping and DNA barcoding (Hardbunnfauna) fortunately overlap quite a bit in where and how we find our animals (as in, Cessa’s seaslugs are eating the organisms the rest of us are studying..!), and so it made sense that we collaborated closely during this event.

That meant more hands available to do the work, more knowledge to be shared – and definitely more fun! All projects had invited guests, mostly specialists in certain groups, but also citizen scientists, and our students participating. We stayed at the field station, which has excellent facilities for both lodging and lab work.

Participants on our Artsprojects workshop in March. Left from back: Peter Schuchert, Manuel Malaquias, Bjørn Gulliksen, Jon Kongsrud, Tom Alvestad, Gonzalo Giribet. Middle row from left: Heine Jensen, Luis Martell, Endre Willassen, Eivind Oug, Front row from left: Katrine Kongshavn, Cessa Rauch and Jenny Neuhaus (Photo: Heine Jensen)

The fieldwork was carried out in the Bergen region, and was done in various ways. We had the R/V “Hans Brattstrøm” available for two days, where we were able to use triangular dredges, plankton net, and grab to sample.

Other days we used a small boat from the station to go to the islands close to Espegrend to examine the tide pools and tidal belt. We also went to local marinas and scraped off what was living on the piers, and a brave soul donned her wet suit and went snorkeling, which enabled us to sample very specific points of interest (“take that green thing over there!”).

We are fortunate here in Bergen in that we have a very active local student dive club, SUB-BSI, whose divers kindly kept an eye out for – and even collected – some of our target animals, as well as sharing their photos of the animals in their natural habitat, all of which is amazing for our projects!
We gave short presentations of each of the projects at SUB in the beginning of the week, and invited the divers out to the lab to on the following Thursday to show some of the things we are working on. It was a very nice evening, with a lot of interested people coming out to look at our critters in the lab. We also decimated no less than 14 homemade pizzas during that evening – learning new stuff is hard work!

Guests in the lab (photos K. Kongshavn)

All together, this made it possible for us to get material from an impressive number of sites; 20 stations were sampled, and we are now working on processing the samples.

The locations where we samples during the week (map: K. Kongshavn)

We are  very grateful to all our participants and helpers for making this a productive and fun week, and we’ll make more blog posts detailing what each project found – keep an eye out for those!

You can also keep up with us on the following media:

 NorHydro: Hydrozoan Science on Facebook, and Twitter #NorHydro

@Hardbunnsfauna on Instagram and Twitter

SeaSlugs: on Instagram and in the Facebookgroup

 Cessa, Luis & Katrine

Sea slug hunt in Egersund!

I’m always scared to look at the current date, time flies! It was already two months ago that we went on a blitz fieldwork trip to Egersund with a very special group of people. But nevertheless, good times become good memories (and especially good museum specimens) and it definitely does not get too old for a small blog about it.

From January 17 to January 21 a small group of sea slug enthusiasts consisting of a student, citizen scientists, a collaborator and museum members rented a van and drove 7 hours down to our Southern neighbor town Egersund.

Egersund was not randomly picked as it is the home town to one of Norway’s most productive and dedicated ‘citizen scientist’; Erling Svensen. Author of a number of books and the most well-known and worldwide used ‘Dyreliv I havet – nordeuropeisk marin fauna’ (English Marine fish and invertebrates of Northern Europe), which amateurs and professionals alike use as an extensive research source.

Erling Svensen’s famous book Dyreliv I Havet

With his almost 5000 dives and counting, Erling knows the critters of the North Sea, big and small, on the back of his hand. Already since the beginning of the sea slug project, Erling was helping providing valuable sea slug species, so it was about time to pay him a visit and bring our team over to make Egersund “biologically unsafe” – enough so to end up in the local news!

We made Egersund unsafe enough to have a small news item about it in the ‘Dalane Tidende’, a local newspaper

The group consisted of Manuel, Cessa, citizen scientist Anders Schouw, collaborator from Havard University Juan Moles and master student Jenny Neuhaus

From left to right Erling Svensen, Anders Schouw, Jenny Neuhaus, Cessa Rauch, Juan Moles and Manuel Malaquias. Photo by Erling Svensen

Jenny just started her Masters in Marine Biology at the University of Bergen in the fall of 2018, she will be writing her thesis on the diversity of sea slugs from the Hordaland county and on the systematics of the genus Jorunna (Nudibranchia) in Europe. The results of this work will definitely become a blog entry of its own.

Jorunna tomentosa, Jennies new pet! Photo by Nils Aukan.

Two of the five days of our fieldwork were basically spendt driving up and down from Bergen to Egersund, it left us only with a good 3 days to get an overview of Erling’s backyard sea slug species. Little time as you can imagine. But time was used efficiently, as Anders and Erling are both extremely good sea slug spotters and with help of sea slug specialist Juan and the eager helping hand of Jenny, Manuel and I were able to identify and add 36 species to our museum sea slug database.

Overview of collected specimens in Egersund

In comparison, we registered 41 one species in Drøbak last year by spending almost a week at the field station! No one thought this would be the outcome (not even Erling himself, as he mentioned that he didn’t find that many sea slug species this time of year on earlier surveys). But we were all very happily surprised, and maybe it was not just luck but also the combination of people we had attending this short field trip. With so many good specialists, either professional or amateur, senior or junior, we were able to work extremely efficient and with a clear communal goal. There was little time spend in reinventing the wheel and explaining the work flow, it was a good valuable exercise that will definitely help us with future brief fieldwork trips and how to make the most from short and tight time schedules. Besides it was a very valuable experience for our student Jenny, as she got first-hand experience with what it’s like to see her study specimens alive, how to handle these fragile individuals, how to sort them from other species and how to document them, which is a good thing to know for her thesis and future career

Jenny learning a lot from the master himself. Photo by Erling Svensen

So yes, all in all our Egersund fieldtrip was short but very sweet!

Furthermore
You want to see more beautiful pictures of sea slugs of Norway! Check out the Sea slugs of Southern Norway Instagram account; and don’t forget to follow us. Become a member of the sea slugs of southern Norway Facebook group, stay updated and join the discussion.

Explore the world, read the invertebrate blogs!

-Cessa & Jenny

New year, new field work!

2019 will bring a lot of field work for us at the invertebrate collections – not only do we have our usual activity, but we will also have *FIVE* Norwegian Taxonomy Initiative projects (Artsprosjekt) running!

On a rather windy Tuesday in January, four of us – representing four of these projects – set out with R/V “Hans Brattstrøm”.

Four projects on the hunt for samples! Photo: A.H.S. Tandberg

Our main target for the day was actually not connected to any of the NTI-projects – we were hunting for the helmet jellyfish, Periphylla periphylla. We need fresh specimens that can be preserved in a nice way, so that they can be included in the upcoming new exhibits we are making for our freshly renovated museum. We were also collecting other “charismatic megafauna” that would be suitable for the new exhibits.

We have been getting Periphylla in most of our plankton samples since last summer, so when we decided this was a species we would like to show in our exhibits about the Norwegian Seas, we did not think it would be a big problem to get more.

This is a species that eats other plankton, so normally when we get it, we try to get rid of it as fast as possible; we want to keep the rest of the sample! But we should have known. Don’t ever say out loud you want a specific species – even something very common. Last November, we planned to look specifically for Periphylla, and we brought several extra people along just because of that. But not a single specimen came up in the samples – even when we tried where we “always” get them…

Lurefjorden is famous for being a hotspot for Periphylla – so the odds were in our favor! Map: K. Kongshavn

Wise from Novembers overconfident cruise, this time we planned to call to the lab IF we got anything to preserve. The Plankton-sample did not look too good for Periphylla: we only got a juvenile and some very small babies. So we cast the bottom-trawl out (the smallest and cutest trawl any of us have ever used!), and this sample brought us the jackpot! Several adult Periphylla, and a set of medium-sized ones as well! Back in out preparation-lab an entire size-range of the jelly is getting ready for our museum – be sure to look for it when you come visit us!

We of course wanted to maximize the output of our boat time– so in addition to Periphylla-hunting, we sampled for plankton (also to be used for the upcoming ForBio-course in zooplankton), tested the traps that NorAmph2 will be using to collect amphipods from the superfamily Lysianassoidea, checked the trawl catch carefully for nudibranchs (Sea Slugs of Southern Norway, SSSN) and benthic Hydrozoa (NorHydro), and used a triangular dredge to collect samples from shallow hard-bottom substrate that can be part of either SSSN or the upcoming projects NorHydro (“Norwegian marine benthic Hydrozoa”) or “Invertebrate fauna of marine rocky shallow-water habitats; species mapping and DNA barcoding” (Hardbunnsfauna).

The Hardbunnsfauna project was especially looking for Tunicates that we didn’t already have preserved in ethanol, as we want to start barcoding these once the project begins in earnest (last week of March). We also collected bryozoans, some small calcareous sponges, and (surprise, surprise!) polychaetes.

When it comes to hydrozoans, we were lucky to find several colonies of thecate hydroids from families Campanulariidae and Bougainvilliidae that represent some of the first records for NorHydro. Hydroid colonies growing on red and brown algae were particularly common and will provide a nice baseline against which diversity in other localities will be contrasted.

Different hydroid colonies growing on algae and rocks at the bottom of Lurefjorden. Photo: L. Martell

There were not a lot of sea slugs to be found on this day, but we did get a nice little Cuthona and a Onchidoris.

But what about the Amphipod-traps? Scavengers like Lysianassoidea need some time to realize that there is food around, and then they need to get to it. Our traps have one small opening in one end, but the nice smell of decomposing fish also comes out in the other end of the trap. We therefore normally leave traps out at least 24 hours (or even 48), and at this trip we only had the time to leave them for 7 hours. The collected result was therefore minimal – we even got most of the bait back up. However, knowing that we have a design we can deploy and retrieve from the vessel is very good, and we got to test how the technical details work. It was quite dark when we came to retrieve the traps, so we were very happy to see them! All in all not so bad!

We had a good day at sea, and it will be exciting to see some of our animals displayed in the new exhibits!


If you want to know more about our projects, we are all planning on blogging here as we progress. Additionally you can find more on the

-Anne Helene, Cessa, Luis & Katrine 

Door #15: The eye of the beholder

It’s funny to see the different reactions to fresh material that comes in to the museum;  the exhibition team had  received some kelp that will be pressed and dried for the new exhibitions (opening fall 2019), and I ducked in to secure some of the fauna sitting on the kelp before it was scraped off and discarded. For the botanists, the animals were merely a distraction that needed to be removed so that they could deal with the kelp, whilst I was trying to avoid too much algae in the sample as it messes up the fixation of the animals.

I chose the right shirt for the day- it’s full of nudibranchs! (photo: L. Martell)

 

I then spirited my loot into the lab, and set up camp.

Count me in amongst the people who stare at lumps of seaweed.

 

Who’s there? The whole lump is ~12 cm.

How many animals do you see here? Which ones appeal to you?

I have made a quick annotation of some of the biota here:

Note that these are just some of the critters present…! (photo: K. Kongshavn)

Let’s go closer on a small piece of algae:

Now, what do you see? (photo: K. Kongshavn)

For Luis, the first thing to catch the eye was (of course) the Hydrozoa

Hydrozoans (the christmas light looking strings), encrusting bryozoans (the flat, encrusting growth on on the algae – you might also know them as moss animals), and some white, spiralling polychaete tubes  (photo: K. Kongshavn)

Did you spot the sea hare (Aplysia punctata?) Look a bit above the middle of the photo of the tiny aquarium with the black background. Do you see a red-pink blob?

Hello, Aplysia punctata! (photo: K. Kongshavn)

There were also several other sea slugs that I have handed over to Cessa for inclusion in the sea slugs of Southern Norway project, here are a few:

Then there were the shelled gastropods:

The brittle star from the earlier image – this is a Ophiopholis aculeata, the crevice sea star (photo: K. Kongshavn)

In fact, they both are Ophiopholis aculeata (in Norwegian we call them “chameleon brittle stars” – they live up to the name!), one of the very common species around here. (photo: K. Kongshavn)

One of the colonial ascidian tunicates (and some of the ever present bryozoa just below it) (photo: K. Kongshavn)

Most of these animals will be barcoded, and will help build our reference library for species that occur in Norway. I also hope that they may have helped open your eyes to some of the more inconspicuous creatures that live just beneath the surface?

2019 will see the start of a new species taxonomy project where we will explore the invertebrate fauna of shallow-water rocky shores, so there will be many more posts like this to come!

-Katrine

Door # 11: Animal rocks and flower animals

The phylum Cnidaria is a diverse group of animals united by their ability to synthesize a complex type of ‘stinging’ cells called cnidocytes, which they use to hunt for their prey. The more than 13 000 species of cnidarians come in many shapes and colors, from the familiar jellyfish and corals, to the less famous myxozoans, hydroids, and siphonophores (read some more about those here). Because cnidarians live and thrive in marine and freshwater environments all around the world, humans have become familiar with them since ancient times: they have been feared for their sting, worn as jewelry, or simply admired for their beauty.

Sea nettles (genus Chrysaora) and ‘terrestrial’ nettles (genus Urtica) belong to very different groups of organisms, but share their name because of their stinging abilities. In some languages, like Norwegian and Swedish, cnidarians are called “nettle animals” (nesledyr and nässeldjur, respectively). Photo: Luis Martell (left), Nannie Persson (right).

Despite this familiarity, the true nature of cnidarians long remained unclear to naturalists and non-professionals alike. Perhaps to a greater extent than any other large phylum in the animal kingdom, people have historically failed to recognize cnidarians as animals, or even as living beings. Early civilizations had some knowledge about corals, sea-anemones and large jellyfish, all of which were encountered frequently along the coasts, but although fishermen and sailors knew about the existence of coral reefs (the massive bodies of coral represented major hazards for navigation), the animals themselves were probably seen only as pieces of rock. Some of the sessile species of cnidarians with a hard skeleton were considered minerals until the second half of the 17th century, when the use of magnifying lenses and the invention of the microscope allowed scientists to realize that the stony coral fragments washed up on the shore were actually made up of small flower-like organisms.

With their tentacles surrounding a central disc, sea anemones (in the image a specimen of Aiptasia) look somewhat like submarine flowers. Their plant namesakes (for example the wood anemone Anemone nemorosa) are strictly terrestrial. Photo: Joan J. Soto-Àngel (left), Nannie Persson (right).

Historically, the most persistent confusion regarding the cnidarians has been with plants and algae. For more than 1 500 years, the immobile sea anemones, sea fans, and hydroids were thought to be strange marine flowers and were consequently studied by botanists, not zoologists. They grow attached to the substrate and many species die if detached, which left early naturalists in doubt as to whether they were plants or animals. Thus, the category ‘zoophytes’ (from Ancient Greek ζῷον, zoon, ‘animal’ and φυτόν, phytón, ‘plant’) was created for them. It was only in the first half of the eighteenth century when this view started to change, thanks to the observations of J. A. Peyssonnel and the work of botanist Bernard de Jussieu, who together managed to convince their colleagues about the animal nature of the zoophytes.

The ‘sea tomato’ (Actinia equina) is a common cnidarian along the Atlantic coasts of Europe. It may look like a tomato when it is not covered by water, but is not related to its vegetal look-alike. Photo: Nannie Persson

The flowers of submerged marine plants (like this Cymodocea nodosa) are usually not as colorful or conspicuous as sea anemones and corals. Photo: Joan J. Soto Àngel

Today we know more about these organisms and there are no longer doubts about their affiliation to the animal kingdom, although we can still see evidence of their botanical past in the names of several cnidarian groups. The word Cnidaria comes from the Greek word κνίδη (knídē, meaning ‘nettle’, referring to the plant genus Urtica), and was inspired by the stinging power of the plants. One of the largest groups of cnidarians, the Anthozoa (which includes the flower-looking sea anemones and corals) is aptly named with a word deriving from the ancient Greek roots for flower (antho-) and animal (-zoa). Because there are still many open questions in cnidarian biology, initiatives that chart the diversity of cnidarians (like the successful project HYPNO and the upcoming project NORHYDRO) are necessary to get to know more about the particularities of these interesting animals!

-Luis Martell and Nannie Persson 


References:

Jussieu, B. de, 1742. Examen de quelques productions marines qui ont été mises au nombre des plantes, et qui sont l’ouvrage d’une sorte d’insecte de mer. Mem. Acad. Roy. Sci. Paris, 1742, 392.

Edwards, C. 1972. The history and state of the study of medusa and hydroids. Proc. R. S. E. (B). 73, 25: 247-257.

Door #10: The Molluscan Forum 2018 in London

Special 20th anniversary 22.11.18
The Malacological Society of London
Conference talk about citizen scientists

A few weeks ago, Manuel Malaquias, Justine Siegwald and me travelled to London in order to attend the 20th anniversary conference of the Malacological Society of London, UK. This society is dedicated to research and education on molluscs. Although based in London (as the name refers to), the society is internationally orientated and welcomes all members interested in the scientific study of molluscs. The society was founded in 1893 and registered as a charity. One of the many activities of the society is to organize meetings and symposia, and this year it turned out to be a 20th anniversary of the molluscan forum!

It was an incredible interesting day with a lot of inspirational posters and talks. My mission for that day was to present our ‘Sea slugs of Southern Norway’ project with the emphasis on how citizen scientist made this project a success. I wanted to share with the audience how citizen scientists with the right approach could be the future for many scientific studies.

Cessa presenting at the Molluscan Forum, 22th of November 2018

But first let us have a look into the meaning of citizen science. According to the Oxford English Dictionary, citizen science is scientific work undertaken by members of the general public, often in collaboration with or under the direction of professional scientists and scientific institutions. The term was first coined during the nineties in the United States of America. Since than it has grown in popularity, with multiple projects in the world that rely on the input of data generated by the general public. Some big and well-known examples are eBird, with roughly 411K users, Nasa Globe with 640K users, iNaturalist, with almost 1 million users and OPAL with 930K users and counting.

Increase of popularity of citizenscience projects per year, Nature 2018

Since the beginning of this year we put a lot of effort in setting up a network of volunteers and underwater photographers. We got many good people willing to contribute to our project and most them are located in the South of Norway, but we also have a few located more further up North in Norway. Currently we have around 150 members directly and indirectly involved in helping us with our project. We try to involve our citizen scientist in the project as much as possible and one way is by reaching out to them via several social media platforms. For example, in our Facebook group community members can participate in discussions about species descriptions and share their findings etc. But we also have an Instagram account that functions as a pocket field guide for followers. Besides we try to keep everyone up to date about the project by regular posting blogs.

Cessa showing the different social media platforms used in the project during the Molluscan Forum

But our key element in this project definitely goes to the assembly and design of our sampling kits. These were designed specially for our citizen scientists in order to make collecting easier, more accessible and more standardized for everyone. By trying to standardize the collecting steps with so-called instructed sampling kits we minimized the errors that could occur during sampling of the data. The sampling kits contain plastic jars for the samples, fixative, preprinted labels and a USB flash drive with enough space for high-resolution pictures and a preset excel file that only needs filling in.

Example of the content of a citizen science sampling kit designed for the Sea slugs of Southern Norway project

We noticed that this approach worked out and the data quantity and quality increased as well the recruitment became easier. When we look at all the Norwegian sea slug records from the museum collection since the 19th century, it consists of roughly 1400 records. In just over six months time we see that the contribution of the citizen scientists covers almost half of that.

A comparison of the amount of records collected by citizen scientists since this year compared to our museum collection

Eubranchus farrani species complex, one species or multiple?

The material that is sent in by the citizen scientists is at the moment being studied by us. We have two master students who will start working in January on a variety of taxonomic challenges by studying the different geographical material.

 

An example of this is Eubranchus farrani species complexes that have different color morphotypes from different geographical locations. Do we deal here with one species or multiple?

Stay tuned for a follow up!

Furthermore
Sea slugs of Southern Norway recently got its own Instagram account! Perfect for on the go if you would like to quickly check some species, click here https://www.instagram.com/seaslugsofsouthernnorway/ and don’t forget to follow us.

Become a member of the sea slugs of southern Norway facebook group, stay updated and join the discussion; https://www.facebook.com/groups/seaslugsofsouthernnorway/

Explore the world, read the invertebrate blogs!

-Cessa