Category Archives: Mollusca

Door #19: Photosynthetic vs solar-powered sea slugs

I think we can all agree that sea slugs are amazing creatures. Some species contain toxins that are useful for cancer research and others are photosynthetic! There are a few species of sea slugs that have the ability to photosynthesize. But beware; the ability for them to do the thing that plants and algae are good at (photosynthesis), doesn’t always mean they are solar-powered. And I will explain you in the next few lines what I mean with that.

There are two families of sea slugs known to have a few species within them that can photosynthesize; it’s within the family of Facelinidae and the family of Sacoglossa.

Within the family of Facelinidae we have the genus Phyllodesmium; and all species in this genus are considered solar-powered, meaning that they get a part of their daily energy intake via photosynthesis. At the moment the theory goes that they are able to do so as they contain photosynthetic zooxanthella stolen from their feeding source (soft corals), and they continue to ‘farm’ these zooxanthellae in their own bodies. The species Phyllodesmium longicirrum masters this trade and is best known as the solar-powered Phyllodesmium

Solar-powered Phyllodesmium longicirrum by Jason R. Marks

The other family does things quite differently but nevertheless as impressive; those are the Sacoglossa.

A few representatives of the photosynthetic sea slugs within the Sacoglossa

Unlike Phyllodesmium, they don’t farm zooxanthella but they steal the photosynthetic cell organelles (chloroplasts or plastids) from the algae they feed on; also known as kleptoplasty (Kleptes (κλέπτης) Greek for thief). Approximately 140 years ago these sea slugs were first described by de Negri and de Negri, who discovered that these sea slugs were green colored due to foreign ‘bodies’ that were reminiscent to those known from plants. It took at least another 100 years before the ‘granule bodies’ were identified to be chloroplasts from the algae the slugs feed on. Sacoglossa are also known as sap-sucking sea slugs because of the way they eat their algae; at first, the sea slugs pinch a whole in the algae wall with their special teeth, called the radula. Then they suck out the cytosolic content of the algae (hence the name sap sucking sea slugs). Finally, the cytosol content is being digested in the digestive tract that perforates the entire body and within some species the chloroplasts are being sequestered and continue to photosynthesize in the animal’s digestive cells

Sap-sucking slug sequestering chloroplasts from the algae it feeds on (figure from Rauch et al. 2015)

Although the sea slugs are famous for their ability of stealing chloroplasts, they only represent a minority within the Sacoglossa. In fact, only 6 out of 300 described species, can keep the chloroplasts fully functional for long term, or long-term retention species; that is the chloroplasts are photosynthetic active for longer than 21 days after sequestration. The gross majority are either short term retention species (with functional chloroplasts up to 14 days or more) or cannot retain the chloroplasts at all (called non-retention species). This means that the chloroplasts are immediately being digested like the rest of the algae content.

So why are Sacoglossa photosynthetic but not solar powered like Phyllodesmium? Well this is because numerous studies observed how the sea slugs died as soon as they were being starved (meaning they couldn’t eat their algae food anymore) even though they had photosynthetic active chloroplasts in their cells. Besides, based on CO2 fixating measurements, it turned out that 99% of the sea slug has to live from normal ingested food, like all other animals do. This could very well explain why only 6 out of the 300 described species are able to sequester chloroplasts long-term, and apparently for reasons other than carbon fixation!

The take home message is that this case of photosynthetic and solar-powered sea slugs is a great example of how good science is about resisting the pull of easy conclusions. When something seems right at first, it should still be testified!

Furthermore
Interested in photosynthetic sea slugs? You can read more in the following papers that are also used as source for this blog:

  1. A sea slug’s guide to plastid symbiosis (2015) J De Vries, C Rauch, G Christa, SB Gould, Acta Societatis Botanicorum Poloniae 83 (4)
  2. Why it is time to look beyond algal genes in photosynthetic slugs (2015) C Rauch, J Vries, S Rommel, LE Rose, C Woehle, G Christa, EM Laetz (…), Genome biology and evolution 7 (9), 2602-2607
  3. On being the right size as an animal with plastids (2017) C Rauch, P Jahns, AGM Tielens, SB Gould, WF Martin, Frontiers in plant science 8, 1402
  4. Mitochondrial Genome Assemblies of Elysia timidaand Elysia cornigera and the Response of Mitochondrion-Associated Metabolism during Starvation (2017) C Rauch, G Christa, J de Vries, C Woehle, SB Gould, Genome biology and evolution 9 (7), 1873-1879
  5. The ability to incorporate functional plastids by the sea slug Elysia viridisis governed by its food source (2018) C Rauch, AGM Tielens, J Serôdio, SB Gould, G Christa, Marine Biology 165 (5), 82

Would you like to see pictures of sea slugs that you can find in 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!

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 #12: Meet the chitons!

Some molluscs, like snails, clams, mussels and octopuses are familiar to most people, but others are more unknown. Among these are the flattened, shell-bearing chitons (skallus/leddsnegler in Norwegian). They are commonly found clinging to rocks in the intertidal zone, and can be found all along the coastline. Many species can be colourful, with stripes, dots and zigzag lines ornamenting the shell plates.

Tonicella marmorea, a common species of chiton in Norway. Photo N. Mikkelsen

The scientific name, Polyplacophora, translates to “bearer of many plates”, and refers to the eight hard shell plates covering the animal. The shell provides protection from predators, and the organization of the shell into eight separate plates also provides flexibility— if disturbed, some species can roll up into a ball like a hedgehog. Surrounding the shell is a tough girdle, which in many species is covered in scales or spines, which also serve to deter any predators.

On the underside, the chiton has a muscular foot that is used for movement and for attaching firmly to the rocks that they live on. They rasp food, like encrusting algae and animals, from the substrate with their radula, a tongue-like structure with several rows of tiny teeth. The teeth are often reinforced with minerals to make them extra durable for scraping on rocks.

The underside of the chiton Tonicella marmorea. The muscular foot can be seen the centre. The gills are seen around the foot to the right. The head with the mouth can be seen on the left side. Photo N. Mikkelsen

Chitons are found in habitats from the intertidal down to depths of several thousand meters, usually on stones or rocky surface. Some species have adapted to other habitats. One of the species we find in Norway is even specialized to live on large sponges in the deep-sea. This chiton grazes on the sponge, and in the process gradually digs out a depression in the sponge perfectly fitted for the chiton to sit in.

Hanleya nagelfar, a chiton that lives on sponges. Photo N. Mikkelsen

Chitons are a very old animal group, with fossil dating back 500 millions years. In fact, their body plan even still bears resemblances to the animals that were among the ancestors of the variety of molluscs in existence today. The chiton’s way of life is apparently an evolutionary successful recipe!

The next time you walk along the seashore, take a close look at a rock and you might find some colourful chitons!

-Nina

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

Course on “Preparation, curation, and databasing of marine biodiversity collections” at University Lurio, Pemba, Mozambique (27th August–7th September 2018)

Manuel shares his recent experience of teaching at University Lurio in Mozambique

My collaboration with the University Lurio (UniLurio) in northern Mozambique started back in 2015 when together we organized a fieldtrip to Vamizi island in the Quirimbas archipelago off the northern coast of Mozambique.

Since then, I had the opportunity to participate in several academic activities; I lectured, have reviewed and evaluated theses for the “licenciatura” degree, and most rewarding I have supervised two master students (2015/17) that are now professors at UniLurio. In 2017 I had the pleasure to integrate a mission organized by the Norwegian Embassy in Mozambique to establish a collaborative programme between UniLurio and Norway and later in the same year I was awarded a “Visiting Scholarship” by the International Council for Science, Scientific Committee on Oceanic Research (SCOR) to teach a course about biological collections at UniLurio.

The tropical location of Mozambique in the Indian Ocean results in an impressively rich biological diversity which is nevertheless extremely vulnerable to climate change and warming of ocean waters.

Aspect of part of the UniLurio wet spider collection and dry collection of corals

Therefore, better knowledge of biodiversity and long-term preservation of biological collections are important tools to better understand shifts in faunal and flora composition and the arrival of new species supporting the definition of mitigation and conservation strategies.

The University Lurio has a “Collections Room” with specimens representing the local fauna and flora with marine invertebrates, reptiles, fish, vascular plants, etc., and has a special focus on the study of biodiversity, but simultaneously acknowledges the need to reinforce its infrastructure and build up capacities to develop and manage its collections.

 

This was the framework that led us to decide to organize the course and apply together for funding with SCOR. Later in 2017 the good news arrived, the funding was approved, and so, suddenly I had an entire new course to put together!

All my entire career from the time I undertook my “licenciatura” thesis back in 1994 all the way up to my PhD, postdocs, until the moment I got my first permanent job (the one I still hold) has been always inside natural history museums (Europe, US, Australia, etc.) and consequently working with biological collections has become part of my daily routines for quite a while! And yes, during these more than 20 years I have seen quite a bit and learn a few things, but suddenly for the first time I had to put together this knowledge in a way that it could be presented and shared with others. It turned out to be quite a challenge…, but definitely a rewarding one!

Course structure

During a lecture on curatorial procedures

Photoshoot before setting off for sampling in a local Pemba tidal flat

At UniLurio the course was attended by 15 participants (8 students and 7 professors / technical staff). It was organized in four lectures (2h each), two sampling trips (ca. 4h each) to the tidal zone to collect marine invertebrates (molluscs, echinoderms, crustaceans, etc.), and three laboratory sessions (4h each) to identify the samples and go through all the necessary curatorial steps to ensure proper preservation for long-term storage of the collection (relaxation, fixation, preservation, DNA samples, registration, labeling).

Registering and labelling the lots

All sample lots generated by the students throughout the course were registered in the UniLurio databasing system following DarwinCore standards and at the end integrated in the biological collections.

Bringing the new curated samples to the UniLurio collection room

We finished the course with a very participated open session where it was discussed how could the new acquired competences benefit the development of the local infrastructure bearing in mind the local reality and constrains. A very interesting exercise confronting ideal scenarios with sometimes the harsh and challenging reality of a country with limited infrastructure capacities and in economical strain. At last we had a simple but cozy ceremony attended by the Director of the Faculty of Natural Sciences, UniLurio where certificates of attendance of the course were handed over to the students.

Certification ceremony with awarding of course diplomas.

The course was sponsored by the International Council for Science, Scientific Committee on Oceanic Research (SCOR), the University Lurio, Mozambique and the University of Bergen, Norway

-Manuel

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!