Category Archives: Sea slugs of Southern Norway (SSoSN)

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 #17: Sea bunnies of Norway?

Some years ago, in 2015, the internet was taken a storm by the sudden rise of the so-called sea bunnies. It all started with a video taken the year before by a SCUBA diver in Japan who filmed the little creatures crawling around the seabed:

The species seen in the video is called Jorunna parva, and are since then worldwide unofficially known by the adorable pet name ‘sea bunny’ as it has a ‘fur’ like exterior with tiny upright ‘ears’ and a fluffy tail like bunnies do. The ‘fur’ is actually created by bunches of tiny rods, called the caryophyllidia. The caryophyllidia are arranged around little knots that are often dark coloured, which create the illusion of black dots on the animals. The seemingly ears are the animals rhinophores, that function as chemical receptors that make the animal able to detect its environment in search of food and other sea bunnies. Its tail on the back are actually its gills to extract oxygen molecules from the surrounding water, the ‘fluffier’ it is, the bigger the surface area, the easier it is to diffuse oxygen from the water. This sea bunny is small, often less than 2.5 cm, and can be found throughout the Indo-Pacific; from South Africa to Central Pacific. They have, like many sea slugs do, a high degree of colour polymorphism in the species, with colours varying from white with black dots, to yellow and even bright orange:

Different colours of Jorunna parva, aka the sea bunny (photo credits on image)

Unfortunately, our sea bunny J. parva is only short-lived and just lives from a few months up to a year, but at least during its short life it doesn’t need to worry about predators. They are very toxic, because of the food they eat, which are sponges. All dorid nudibranchs (the group of slugs J. parva belongs to) are toxic because of their diet, and these toxins are often used in cancer treatments for people. Who would have thought that sea bunnies would be lifesavers, besides  being cute? But is the word sea bunny only referring to this particular species called J. parva? A quick search on the internet definitely tells us otherwise, it seems people refer to sea bunnies when they talk about any other dorid nudibranch with a fluffy and round appearance.

So, the question remains, do we have any sea bunnies in Norway? And the answer is yes, we do!

Sea bunnies of Norway (click to enlarge!)

And they are absolutely great and adorable to encounter underwater. Let us make a list of the sea bunnies of Norway, so we know what species we are talking about. Sea bunnies of Norway are; Doris pseudoargusGeitodoris planataJorunna tomentosaRostanga rubraCadlina laevis, Aldisa zetlandicaAdalaria loveniAdalaria proximaOnchidoris muricataOnchidoris bilamata,
Onchidoris pussilaOnchidoris depressaAcanthodoris pilosaDiaphorodoris luteocincta and I personally would draw the line at Goniodoris nodosa, as the other Goniodoridae don’t resemble that much the typical sea bunny characteristics. What do you think? Which species do you think are missing in this list, or which species should be left out?

I think it is time to take over the internet with our sea bunnies of Norway!

 

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

Door #16: Basic anatomy of the sea slug

Haminoea sp, photo by M. Malaquias

“Sea slugs” include both the by far most famous nudibranchs, and groups such as the Sacoglossa (sap-sucking slugs, more about these later in the calendar!) and Cephalaspidea (the bubble snails), amongst others. These latter ones often do have shells – but reduced ones, too small for the animals to completely retreat into, like this Haminoea:

Nudibranchs, however, are the “naked” snails: Their name “nudibranch” comes from the Latin nudus, naked, and the Greek βρανχια, brankhia, gills. They don’t have a shell, but this wasn’t always the case. In their early larval life stage, they actually have a shell, but when settling down and transforming from zooplankton into adults, they lose the shell. The loss of the shell in adults might be responsible for the amazing diversity we see in body forms present in sea slugs.

So, in this basic anatomy of sea slugs we will focus mostly on the body forms of nudibranchs, but all other sea slug orders are not far off from this anatomy, if you know the basics of nudibranchs, you can extrapolate to the other orders as well. So here we go!

Nudibranchs are roughly divided in two type of body forms; the dorid nudibranchs and the aeolid nudibranchs.

Two basic body types found within the Nudibranchia; the dorids and the aeolids. (Illustration: C. Rauch)

The dorid nudibranchs have a thick mantle that extends over their foot. In some species the surface of the mantle is covered with tubercles than can vary in different sizes, numbers and shapes. This gives them often a rigid body that offers some protection.  In most of the dorids it is the mantle that contains toxins to defend themselves, the toxins are extracted from their food sources.

Aeolid nudibranchs have mantles that are covered with finger-like extensions called cerata. The cerata are very special as they contain branches of the digestive tract, and in some species, this is also visible! The tips of the cerata contain special organs called the cnidosacs. Cnidosacs store stinging cells (called nematocysts). These are obtained from their food source which are often cnidarians like hydroids, sea-anemones and soft corals. The cnidosacs are activated when the nudibranchs feel threatened and the stinging cells will be discharged!

All sea slugs have rhinophores. On the head of all sea slugs you can find a pair of sensory tentacles called the rhinophores. They detect smell and taste and in most of the dorid nudibranchs the rhinophores can be retracted into a basal sheath. Sea slugs know all kind of shapes of rhinophores which are a very important tool for identification of the species.

Diversity of sea slug rhinophore shapes

Besides a pair of rhinophores many nudibranchs also have a pair of oral tentacles, one on each side of the mouth. They are most likely involved in identifying food by taste and touch.

Sea slugs also need to breathe oxygen. They do this via the surface of their entire bodies, but their main reparatory organ are their gills. Dorid nudibranchs have often a feather like structure encircling their anus on the back of their body (the branchial plume). Some dorid species can also retract their gills into a pocket. Within the aeolid nudibranchs the cerata act like gills by diffusing oxygen from the surrounding water. The cerata are sometimes branched in order to increase the surface area, also here, like the rhinophores, different species can have different forms of cerata.

Diversity of aeolid cerata shapes

-Cessa

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 #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

Door #3: Mollusc hunting around the world

The study of molluscs (malacology) has a long tradition in Norway. Despite the nearly 50,000 species dwelling in the world oceans and seas, a number only barely supersede by the arthropods, new species continue to be discovered and our understanding of the relationships and systematics of molluscs to change.

At the Natural History Museum of Bergen, the study of molluscs is focal, and research is carried out on various aspects of their diversity, morphology, ecology, systematics, evolution, and biogeography, using state of the art methods like DNA barcoding, molecular phylogenetics, and electron microscopy. Understanding the patterns and processes that drive present diversity in the oceans is one of our main goals and our research foci are framed within several “big questions”: How many and how can we differentiate between species? How do species originate in the oceans? Why some regions in the oceans are more diverse than others? Are mechanisms responsible for the patterns of diversity in the deep-sea the same as in shallow ecosystems?

Our quest for answers necessitate the continuous collection of new specimens and the exploration of remote geographies. We conduct regular fieldwork around the world including Norway, through numerous projects and partnerships.

Here are some snapshots from recent fieldwork from Manuel & team:

Working during October 2017 together with Professor João Macuio from the University Lurio (Pemba, Mozambique) in Nangata Bay (Nuarro, Mozambique) on a survey of the sea slug diversity inhabiting this pristine coral reef area and on an assessment of the structure and conservation status of the population of the threatened giant clam species (Tridacna maxima). Left image: Manuel Malaquias and João Macuio photographing sea slugs at the Nuarro Research Center.

João Macuio measuring underwater the total length of a specimen of the giant clam Tridacna maxima

Working in remote places requires often some capacity to improvise and during a fieldtrip to Taiwan while in the Penghu islands we had to convince the manager of our hostel to let us set up a field-lab in the garage among his gear and pet-cage!

Manuel and Trond Oskars, PhD candidate at the Museum, searching for molluscs during May 2017 at mangrove systems near the city of Kaohsiung, Taiwan

In the Penghu islands we had the opportunity to work in the field together with students from the National Penghu University of Science and Technology, here depicted in the right image helping collecting sea slugs along a water stream lined by few mangrove bushes.

After a three weeks fieldtrip to Vamizi island in the Quirimbas archipelago, north of Mozambique during May 2015, we were finally brought to shore at Palma village near the border with Tanzania where we had to do some final sorting and organization of samples under the curious eyes of the local villagers (Manuel Malaquias and Yara Tibiriça from the Zavora Marine Lab in Mozambique).

Fieldwork during May 2018 in the Oslo fjord as part of the project “Sea slugs of southern Norway” funded by Artsdatabanken. Left image: part of the team working through the catch of the day at the Tolboden Course Center in Drøbak, University of Oslo (left to right: Cessa Rauch, Manuel Malaquias, Torkild Bakken, Anders Schouw)

You can read more about some of these expeditions by exploring the posts found here (workshops) and here (fieldwork).

Manuel

NorBOL and BOLDsystems course Trondheim 17th-19th of October

Travelogue from Cessa Rauch

Today the weekly event of MolluscMonday and the annual SeaSlugDay (29th of October) coincide!Bunch of sea slugs to celebrate sea slug day, collected in Askøy

What better way to celebrate it with another blog! Much has happened again since the last blog in August, in which we went on fieldwork in Askøy by joining the ladies of the jentedykketreff to find sea slug species in the Bergen area. We officially started to barcode our first specimens, got two new master students that will also work on the project by looking into a variety of topics (diversity of sea slugs in Hordaland, population genetics of Polycera quadrilineata and taxonomy of the genus Eubranchus).

In this blog I will share with you how we are uploading our slugs to the World Wide Web with help of the Barcode of Life data system and how the Norwegian Barcode of Life is helping us getting this done by organizing an informative course in Trondheim.

First step in trying to decode our precious species
The sea slugs of Southern Norway project is a two-year project funded by Artsdatabanken (The Norwegian Taxonomy Initiative) with the aim of mapping the biodiversity of sea slugs along the Southern part of the Norwegian coast

Sea slugs of Southern Norway being eaten by Doris pseudoargus

The focal area stretches from Bergen, Hordaland, all the way down to the Swedish border. In May, July and August of this year the project successfully completed its first fieldwork trips with an additional of 500 new registered museum specimens that cover roughly 90 sea slug species. The species names are attributed based on morphological characteristics, but several species exhibit amazing colour polymorphism, possibly hiding cryptic diversity.

Moreover, we cannot discard the possible occurrence of alien species with similar morphotypes to the native fauna. Therefore, we will need to DNA barcode our specimens to either confirm or change the species names credited to our collected specimens. Besides it will give us an overview for the relatedness of the sea slugs to one another and unravel maybe new species!

In order to successfully sequence 500+ specimen the project collaborates with the Norwegian Barcode of Life project (NorBOL). NorBOL is a network of Norwegian biodiversity institutions and individual scientists that coordinates the establishment of a library of DNA sequences (barcodes) of the fauna and flora of Norway. These barcodes)will be submitted to the open access database BOLD (Barcode of Life Data System), as part of the global Barcode of Life initiative and the International Barcode of Life project (iBOL).

Barcode of Life Data System course
Barcode of Life Data System (BOLD) is a globally orientated online workbench and database that supports the assembly and use of DNA barcode data, and is open access to the scientific community and public. At the moment it holds a record of 6235000 barcodes; 194000 of those are animal species, 67000 plant species and 21000 fungi and other species. The BOLD system is an amazing tool to work with for those interested in biodiversity research. Initially it can be a little overwhelming to fill in all available data into Excel file after Excel file, as this is mandatory and needs to be uploaded first to the system before any sequencing can be done. Especially for those who have many specimens to work with. But afterwards the reward is very fulfilling as you, in an instant, can see distribution maps, trees and images of all the specimens uploaded.

Distribution map from Google earth with collected sea slugs from the Oslo area

Image library of all the collected sea slugs

It is the perfect tool for digitizing, analysing, storing and accessing your genetic and image library data from everywhere anytime. BOLD system standards for uploading actual specimen data are pretty high, the quality of what you can find on the platform is good, but in order to keep these standards great, NorBOL organizes special multi day courses for users in order to guide them through all the steps and features of the BOLD system. This year the course was organized by the NorBOL National coordinator NTNU in Trondheim.

It would take three full days of getting together with fellow participants and going through all the steps necessary in order to start a successful project in the BOLD platform. This year it took place from 17th till 19th of October and as such, me, Anna and Per travelled that Wednesday the 17th very early in the morning to Trondheim. The course was well attended with participants traveling from all over Norway and even from its neighbouring country Sweden. The first day consisted mainly of introduction talks and familiarizing ourselves with the many new abbreviations; NorBOL, BOLD, iBOL (et cetera).

It was a nice experience to meet and talk to other biologists working on such interesting topics, varying from flies, mites, sponges, jellyfish, worms, variety of plants, etc. Everything was taken care off, we could check in to our hotels and in the evening, we had a dinner together with the organizers and participants. The next two course days we were asked to work with our own brought specimens. The days consisted of registering the specimens, filling in as much data per specimens as possible. After finishing and uploading the first datasets, it was time to make pictures of every species, before sampling them for DNA barcoding tissue. Almost all participants brought a 96 wells plate worth of specimens so you can imagine the work that was put into getting everything finished in such a short amount of time.

Sea slug tissue in a 96 well plate ready to be shipped for barcoding

The course was an excellent way to get used to the different steps necessary in order to make the submission process a success. And it was very helpful that at any given moment we could ask the course organizers for advice during the preparations of the datasets and the submission.

All the participants were very excited about the course and happy they attended, it was nice meeting new people and as for someone that moved to Norway, a good opportunity to finally also see Trondheim, with its amazing large Cathedral, a real eyecatcher

 

 

Sea slug goals
The goal for the sea slugs of Southern Norway project is to barcode all, or at least as much as possible, collected specimen, in order to attribute species names to them, expose cryptic species, maybe find new species and look out for invasive and or alien species. Thanks to this course the first 95 species will be barcoded soon and be added to the image library that we already managed to set up (Image 8. Screenshot of the project page of sea slugs of Southern Norway in the BOLD system workbench).

Screenshot of the project page of sea slugs of Southern Norway in the BOLD system workbench

We are very much looking forward for the first results to be accessible and to analyse the data; keep an eye on the invertebrate blogs because for sure the follow up of this story is going to be pretty exciting.

Acknowledgements
I would like to thank Aina Mærk Aspaas for the coordination of the course, Katrine Kongshavn to help out with my first introduction to NorBOL and the BOLD system workbench and Anna Beata Seniczak and Per Djursvoll for being great colleagues during the course and lovely companions in discovering Trondheim together as real Bergen tourists!

 

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 or just want to look at pretty pictures; click here, and don’t forget to follow us.

Curious about what we have been doing so far,  read about it in our blogs on the invertebrate website;
First fieldwork blog Drøbak may 2018;
Second fieldwork blog Haugesund July 2018;
Third fieldwork trip august 2018

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

Why is it SeaSlugDay today? Read more about that here!  (link goes to Echinoblog)

Explore the world, read the invertebrate blogs!

-Cessa

Fieldwork during the “Jentedykketreff”

Askøy Seilforening 24th till 26th of August 2018
by Cessa Rauch

Jentedykketreff
Every year a group of female divers from all over Norway organize a meetup at one of the many beautiful dive sites along the Norwegian coast. This year they decided to meet up in Askøy at the local seilforening. As this is close to Bergen, me and my colleague Justine Siegwald decided to check it out and see what the ladies would encounter underwater. The meetup was short, and so was our fieldwork, but nevertheless the participants were able to collect a bunch of sea slugs and we added 6 more species to our database, hurray for our citizen scientists!

Sea slugs of Southern Norway – so far
The sea slugs of Southern Norway project is a two-year project funded by Artsdatabanken with the aim of mapping the biodiversity of sea slugs along the Southern part of the Norwegian coast. The focal area stretches from Bergen, Hordaland, all the way down to the Swedish border. From the beginning we have made an effort to engage divers and underwater photographers passionate about sea slugs and establish a network of Citizen Scientists, and the response was extremely positive. Citizen scientists are volunteers that help out scientists by providing them with data as a hobby in their spare time. In May the project had its first official launch with a successful expedition to Drøbak, a little village well known for its marine biology institute, near Oslo in the Oslofjords. In just two weeks we were able to collect around 43 species.

Overview of almost all collected species during the Drøbak expedition in May 2018

Two months later we headed to Haugesund to attend the Slettaa Dykkerklubb dive camp. This camp covered two weeks and attracted many participants. During the dive camp I lectured about sea slugs and especially how to find, recognize and collect them. It was a huge hit and Sea slugs of Southern Norway suddenly counted many new citizen scientists. They were able to add another 22 sea slug species to our database.

Overview of all the collected species during the Haugesund dive camp in July 2018

What did you do this weekend?
Friday afternoon Justine and I were picked up from the institute by the organizer of this years’ yentedykketreff; Gry Henriksen.

Grys’ car turned into a game of Tetris

We actually didn’t really communicate well enough about the car size and very soon we realized that with our personal belongings and portable laboratory gear the car changed into a game of Tetris 

Luckily everything fitted and off we went for our short car ride to Askøy Seilforening. Just a little over an hour drive later we arrived at our destination and we were amazed to see what a luxurious weekend was waiting of us. The seilforening lets us use basically all the space they had, which consisted of a big warehouse were the participants could store their gear, a big ‘club’ house with a kitchen and enough space for all participants to have dinner together. Not to mention the eight tiny houses right at the shore, provided with everything you needed and more.

Askøy Seilforening (from www.askoy-seilforening.no)

 

Right after the arrival Justine and I converted the living room of our rental holiday home to a popup sea slug laboratory as that same evening the ladies already went for their first dive and of course collected some sea slugs for us.

Justine sorting sea slugs in the living room

It is not real sea slug season anymore (best times are more towards winter and early spring) so the collections were dominated mostly by two species; Limacia clavigera and Adalaria loveni.

Limacia clavigera up and down Adalaria loveni on brown kelp

But as the weekend progressed we could add some variety to this list with species as Elysia viridis,  Aplysia punctata, Edmundsella pedata and Cadlina laevis 

Elysia viridis

 On Saturday, after dinner, I gave a short talk about the project and showed the participants pictures of the slugs and brought sampling kits for whoever wanted to contribute to the project. That same day some divers had already collected species which we put in a plastic tray so everyone could have another good and detailed look at

Bucket full of sea slugs (and flatworms)

A memorable success of the weekend was that Gry Henriksen found her first Elysia viridis in the wild during her dive after Justine and I carefully described the way to spot them. Elysia viridis is often overlooked by divers because it lives relatively shallow, between 1 maximum 5 meters. It mostly sits in the green algae (or red as we see it in the picture above) . It is actually easier to see them while snorkeling than diving, but it is still possible! On the last day of the event Gry found hers and collected them for the project! Sunday most off our activities consisted of packing our gear and await one more last catch of slugs from the morning dive. Even though the amount of new species to the list was low, I was happy that we were welcome during this get together weekend as both me and Justine met a lot of old and new faces and were able to engage them into the project. The participants inspired us for setting up a ‘sea slug course’ that we hope to be able to realize the end of this year together with Gry Henriksen and the Askøy Seilforening! So, keep your eyes out for the next blog post as a lot off activities within the project are still to come!

Acknowledgements
I would like to thank Justine Siegwald for being an excellent helping hand during the weekend. And I would like to thank all the participants of the jentedykketreff; Runa Lutnæs, Brit Garvik Dalva, Sofie Knudsen, Laila Løkkebergøen, Silje Skotnes Wollberg, Sissel Grimen, Hege Nyborg Drange and last but not least, the organizer of this event; Gry Henriksen!

 

Furthermore
Interested in where we stayed during this weekend? Check out the website of Askøy Seilforening, they have excellent facilities also for (marine biology) courses; http://www.askoy-seilforening.no

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.

Curious to the other expeditions we did so far? Read about it in our blogs on the invertebrate website; first fieldwork blog Drøbak may 2018 https://invertebrate.w.uib.no/2018/06/04/fieldwork-and-friendship/ and second fieldwork blog Haugesund July 2018 https://invertebrate.w.uib.no/2018/07/20/seaslug-fieldwork-during-the-haugesund-dive-camp/

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!

SeaSlug Fieldwork during the Haugesund Dive Camp

Haugesund 3rd till 10th of July 2018. 
by Cessa Rauch

The Sea slugs of Southern Norway project is going strong with already the second fieldwork trip checked off from our to-do list. Sea slugs of Southern Norway is a two-year project funded by Artsdatabanken aiming to map the diversity of sea slugs along the Southern part of the Norwegian coast. From around Bergen, Hordaland to the Swedish border, as this particular area of Norway has a huge gap of about 80 years without any dedicated work on sea slugs diversity being carried out. In May the project had its official kick off with a successful expedition to Drøbak, a little village near Oslo in the Oslofjord, where we were able to collect around 43 species, and met up with our dedicated collaborators from that area.

A selection of the species collected during the Drøbak expedition in May 2018. From left to right; top: Jorunna tomentosa, Doto dunnei, Facelina bostoniensis, middle: Doto coronata, Fjordia lineata, Limacia clavigera, bottom: Caronella pellucida, Microchlamylla gracilis, Rostanga rubra, photo credits: Anders Schouw

From the beginning we have made an effort to engage divers and underwater photographers passionate about sea slugs and establish a network of Citizen Scientists, and the response was extremely positive. Citizen scientists are volunteers that help out scientists by providing them with data as a hobby in their spare time. Their many years of experience result often in the accumulation of an immensely valuable knowledge about the taxonomy and ecology of these animals, which they eagerly share with us. We shall say, that the success of our project heavily rely on their input and willingness to help collecting samples, particularly because of the restrictions with scientific diving in Norway that we researchers face, that basically hamper any possibility to use this method for collecting slugs during our working time.

Dive camp Haugesund 2018

So far, we have citizen scientists helping us collecting sea slugs in the Oslofjord area, Egersund, Bergen, and Kristiansund. As you can see we miss a lot of coastline here still. Therefore, we decided to participate in the dive camp in Haugesund this year to see if we could get in touch with more enthusiastic hobby divers.

The dive camp was organized by the Slettaa Dykkerklubb Haugaland. Started in 2015, they are a relatively young club, but they grew very fast and have currently around 200 members. They are well known for the many activities they organize throughout the year that are often open to anyone who likes to participate.

Dive camp Haugesund pamphlet and picture

The timetable for the week (click to enlarge)

This year they decided to organize an actual dive camp that took a week and offered two dives a day, camping spot, breakfast, lunch, dinner, and every day an interesting talk or tour related to diving. It was from 4th of July until the 10th and every day between the dives the participants had interesting meet-ups with marine biologists (like Vivian Husa), underwater photographers (Siv Pedersen and Vidar Skålevik from WEDIVE.no), and underwater artist Jason deCaires Taylor. We also visited the company Kystdesign, and we got a safety lecture form Tor Oppegård.

One of the remote-controlled submarines that were presented during the tour

A very busy and informative week! It was a great success for the participants and organizers and there will be a similar event again next year.

There and back again

Microscope in the living room

The day before the camp started, I met with citizen scientist Anders Schouw, and we drove that evening from Bergen to Haugesund to check into our rented Airbnb flat.

Although the Dive Camp had arranged a camping ground for visitors, we decided to stick with renting a flat, in order to have our equipment properly installed. Once arrived, we had to add some adjustments to the apartment. The dining area was converted to a sea slug studio with trays and camera equipment installed. The living room was now our little laboratory with a microscope and laptops.

The dining area converted into our mobile sea slug studio and picture

I can reassure you that we left everything clean and tidy!

The review of the owner, after I left our converted laboratory for an actual apartment

The next day we met very early in the morning at the seashore to be picked up by one of the organizers of the dive camp.

Pick up by speedboat in order to cross the water

The actual event took place on a tiny island just a short boat ride away from the city center of Haugesund. From there we took the boat Risøygutt from Thomas Bergh that we used in order to commute from the island to all the beautiful diving spots surrounding Haugesund. The first day we met up with Klaus and Are Risnes (father and son) as one of the participants of the camp that day.

During the week, and especially during the weekend, the number of participants increased and at a given time we had to go out with two boats in order to bring the more than 20 divers to the dive spots. Anders would be diving with Thomas while Karl Oddvar Floen and Torbjørn Brekke were leading the dive.

Originally built as a shrimp boat, Risøygutt has converted to a diving boat years ago, and the current owner Thomas Bergh, continued to use it for diving activities

My main purpose during the dive camp was providing everyone with collecting jars, that they took with them every dive, in search of sea slugs.

Klaus Risnes after a dive within his collecting jar with the sea hare Aplysia punctata, notice the purple colored water, ink from the sea hare they produce when they are disturbed

The cool box with sea slug samples on Risøygutt, accompanied with Anders’ photography gear

Because we needed the species alive for photography and species identification, I brought a cool-box with ice with me on the boat were the jars with sea slugs were kept, in order to keep them cool.

I was running around on the boat  providing collecting jars to the divers during the whole week, but as the number of participants during the week increased, the collecting jars were running out.

Halfway, Anders and I decided to visit the local supply store and purchased a bunch of extra collecting jars for all the enthusiastic participants willing to catch some sea slugs for us

Collecting jars full with different species of sea slugs

Different sea slug species in a collecting jar (accompanied with three flatworms)

Every day after the two dives, Anders and I returned to our “Airbnb-lab” and started working on the sea slugs, that meant sometimes short nights, and as you guessed it, the more species, the less sleep

Working on collected specimen far past bedtime

The species collected were luckily all photogenic and we were very happy with the results!

Anne Mari With Ottesen helping out with sea slug sorting

 Luckily we got many enthusiasts helping out and one evening Anne Mari With Ottesen joined us on the identification of the sea slugs.

Halfway in the dive camp week I gave a lecture about sea slugs in general and about the Sea slugs in Southern Norway project. It helped divers to spot sea slugs easier as they become better informed about what and where to look for.

This helped tremendously as we continued to get different species of sea slugs after every dive. At the end of the week, the count was on 22 species!

Catch of the week, as it is our most rare species so far in our Artsdatabanken database, Aegires punctilucens, photo credits Anders Schouw

Photogenic Edmundsella pedata, photo credits Anders Schouw

Besides the good weather, the delicious seafood and many new friendships made, with the number of new slug species added to our list and the many new citizen scientists volunteering for our project now, I could say that the dive camp was a success. We will continue to collaborate with Slettaa Dykkerklubb and hopefully in the future will host a sea slug course for its members and participate with the dive camp again next year, I can’t wait. Tusen takk!

Acknowledgments

We would like to thank Anders Schouw for all his effort in helping out during this week and I especially would like to thank him for his stamina during long days and short nights sorting the sea slugs!

We also would like to thank the organizers of the dive camp and Slettaa Dykkerklubb members; Åge Wee, Lars Einar Hollund, Thomas Bergh, Elisabeth Bergh, Torbjørn Brekke, Karl Oddvar Floen, Anne Mari With Ottesen and the numerous other enthusiastic participants that helped us out during the week! And a warm welcome to our new clan of citizen scientists!

Interested in our Sea slugs of Southern Norway project? Become a member of our Facebook group and get regular updates.

 

Further reading

Are you interested in the Slettaa Dykkerklub Haugaland? Visit their Facebook group or their website for more information.

Want to know more about underwater photography? Check the personal underwater photography blog on Facebook or visit this website for tips and tricks.

Always wanted to know more about Jason deCaires Taylors’ underwater art? Visit his website. Did you know that Jason has also underwater art installed in Oslo? Check this out;

Explore the world, read the invertebrate blogs!

Fieldwork and friendship!

Drøbak 6th till 15th of May 2018

The Norwegian Taxonomy Initiative  funded project Sea slugs of Southern Norway  had its official kick-off with its first expedition to Drøbak, a little village on the east side of the Oslofjord about 40 km south of Oslo. Main goal, start mapping the sea slug species diversity of that area which we will continue to do so along different carefully chosen locations along the Southern Norwegian coast. But besides finding sea slugs, we had another ambition; meeting up with our hard-working collaborators that would help us out during our stay.

Sea slugs of Norway, a love story

Sea slugs are often a diver’s favourite encounter underwater. They are colourful, have an overall attractive appearance, with their little rhinophores exploring their surroundings, gliding slowly through their habitat.

Caronella pellucida, photographed by Anders Schouw

They are exciting to photograph as, besides pretty, it can be technically very challenging to get a good shot of them since they are often just a few millimetres long. Despite being popular animals, relatively little is known about them. Just recently the attention from the scientific community started to grow, and manuscripts with new records and species for Norway become to be published. However, the target areas were often the Northern territories of Norway rather than the South, and this resulted in a huge gap lasting already for about 80 years within the scientific literature for this particular area. About time to do something about it!

The citizens that are scientists

Southern Norway alone has a coastline of about 8000km, which makes it a monstrous task to really get a proper picture of the sea slug biodiversity (let alone cryptic species variation, invasive species etc.). Therefore, we asked for help from the so-called citizen scientists. Citizen scientist are volunteers that help out scientists by providing them with data as a hobby in their spare time. Many of them are not to be considered amateurs though, due to their many years of experience and enthusiasm, they are professionals when it comes to their knowledge of species and their habitats. Such a tight community is also found here in Norway within the dive community, and during this project of our hunt for sea slug species, we heavily rely on their input and willingness in order to make the mission a success.

Back to Drøbak

It was not a blind pick on the map to go to Drøbak as our main starting point. Drøbak is strategically chosen as former literature describes it as a type locality for a variety of the Norwegian sea slug species. Besides, the University of Oslo has its Marine Biology field station, with sleeping facilities, located here. Near the field station, there is also the – all famous – dive centre called Gylte, were many dive enthusiasts rent their gear, fill up their pressure tanks and go diving in the centres’ backyard. Not surprisingly one of the workers of Gylte is big sea slug enthusiast; let me introduce you to Tine Kinn Kvamme

Manuel Malaquias with Tine Kinn Kvamme

There was great excitement from both parties to finally meet in person and she was able to help us get in touch with other citizen scientists and explain in detail about all the species she encountered in the last years. The list was impressive,and a valuable contribution to our project;

Tine’s sea slug species check list for the area

That week we managed to meet up with her several times, and she brought us more sea slugs. We introduced her to the laboratory facilities in the Marine field station, where she had the opportunity to look at her beloved Doto’s in detail with help of a microscope, while telling us more about other possible interesting locations and possibilities to collect different species! This is what it is all about, happy scientists and happy citizen scientists!

Doto fragilis

Two other members of our team that joined us during the length of our stay in Drøbak were the respected divers Anders Schouw (from Bergen) and famous underwater photographer Nils Aukan (from Kristiansund).

Anders Schouw showing his photography skills in the laboratory

It was an honour to be able to work together with them, Anders proved his photography skills both underwater and above water to be of incredible valuable input and Nils great knowledge of Marine life and amazing photography skills made me and Manuel blush on our cheeks more than we would like to admit. They both dived every single day during our stay and brought sea slugs back to the laboratory where we together could identify, photograph, measure and prepare them for transport back to Bergen. Nils Aukan is a known sensation within the Norwegian diving community and ever since the project started we have received many samples from him. He is able to photograph the species in their natural habitat capturing the tiniest details, a valuable asset to later identify the species properly.

Fjordia lineata photographed by Nils Aukan

Anders is the guy every expedition need; he knows everyone, everywhere, and we’re very happy to announce his decision to join us in our next field work trip to Hagesund (in July, facilitated with a blog, obviously).

The gate to grass

At the spot we also met with the citizen scientist Roy Dahl, his son and Heine Jensen

Heine Jensen with Manuel Malaquias

A snapshot of the group, from left to right; A snapshot of the group, from left to right; Roy Dahl’s son, Roy Dahl, Anders Schouw, Cessa Rauch and Nils Aukan

Roy and Heine have been collaborating and sampling for us in the Oslofjord area. They know their favourite diving spots on the back of their hands and shared with us all the details one needs to know about the sea slugs’ habitat. They knew about species diversity, where to find but also when to find them. There is some change in sea slugs’ diversity when it comes to different times of the year, some species thrive just before spring starts, others are more regularly seen throughout the summer. All interesting and valuable information for us in order to see the bigger picture. Most diving spots were easy accessible and well facilitated, but sometimes the hunt for different habitats does not always favour you in a laidback access to the water. Manuel and I were a little obsessed with probing for sea slugs within the seagrass meadows of the Oslofjord. You never know what you can find there! Healthy seagrass meadows are the nursery, hiding, and hunting ground of many marine organisms, and we would not let the opportunity to study this habitat pass by!

Facelina bostoniensis on sea grass photographed by Anders Schouw

Anders was able to find an area of seagrass that seemed to be accessible from the Google maps point of view. But was it in real life though? After driving around, back and forwards for almost an hour we sadly realized that the only land access was through a private condo, closed by a gate and inaccessible to us. Whilst driving around a little unsure about what the next plan of action would be, Anders decided to use his communication skills to find out if there was another way. By a matter of luck, chance, sign – you name it – Anders asked the way to a person that happen to live there and to have a remote device that could open the gate giving us access to the park. All together it took us a whole afternoon to figure out how to get to the seagrass meadow and I think we can vote for Heine Jensen as our most patient citizen scientist! As we were driving in many circles to find the sea grass meadows, Heine jokingly mentioned, ‘look, there is grass just next to the road, why don’t we look for our slugs there’. We definitely own him one for his stamina!

You reap what you sow

After 10 days the sea slug teller was on approximately 39 species, and this without the species collected by the citizen scientists before our fieldtrip. All together we have so far assembled 43 species from areas in the Oslofjord. The work has just begun, and as a consequence of our successful actions in Drøbak, we now have to face the mountain of work waiting; structuring our harvest and make some sense of it all in the light of evolution.

For frequent updates, awesome images, and much more information about sea slugs in Norway than you ever imagined encountering, join the projects Facebook group 

Acknowledgments

We would like to thank our collaborators during this project; Torkild Bakken from Trondheim University who was also part of the Drøbak team for a few days, and our dedicated citizen scientists; Anders Schouw, Nils Aukan, Tine Kinn Kvamme, Roy Dahl and Heine Jensen. We hope that during the two years of this project we will have many more chances to meet and that our teamwork continues to be fruitfully!

By Cessa Rauch and Manuel Malaquias