1st GROC's opistobranch course in english

On Sunday 7th of August, the GROC organised a course on the basics of biology and ecology of opisthobranchs, particularly focused on the species commonly found in the Catalan coast, for the staff and volunteers at Kenna Ecodiving (http://www.kennaecodiving.net/), which like GROC is a nonprofit organisation that helps in the marine conservation research programme that studies the populations of posidonia seagrass in the Costa Brava of Catalonia. Since both associations focus their activities on some of the same geographical locations over the coast, it was a good idea from the part of Gaynor at Kenna to ask the guys at GROC to share their knowledge and expertise on the matter, wich materialised in the nice initiative that made this course possible.

We arrived early in the morning at the diving centre near the port of l'Escala, and were warmly welcomed by Gaynor and her crew, who were very helpful at all times and very eager to learn about our slimy underwater friends. We set up the video beam with the computer and everything and before we knew it, the fun had started already. Guillem started our presentation with a brief introduction about the GROC, its activities and scope, and after this Miguel talked a little bit about the opisthobranchs, their position within the animal kingdom, and the distinctive features that make them beautiful and rare.

After we finished in the classroom we were finally able to see some action and went to Punta del Romani dive site where we suited up. Some of us, like normal people wearing wetsuits, and others as if were about to dive under a glacier wearing drysuits, hoods, and gloves. A little too much guys, don't you think? :).

In the first dive we split into two groups, the first one formed by Irene, Gaynor, Martin, Stewart, Guillem and Miguel; and the other group with Issy, Adam, Marc and Toni. The first group was guided by Irene, who has a keen sense for locating nudibranchs. Every time she found something interesting gave the alarm call and Guillem came quickly to take some pics and show the discovery to the group. We lost track of Marc and Toni, and assumed that Issy and Adam were in good hands. But when we came back to the surface we heard stuff like: "you should gave them a compass for their birthday" and that is when we found out that the once experimented divers needed to take the advanced course again… Don't forget to do it guys, we are gonna get you that compass anyway :).

Overall the dive was quite good, we saw a lot of slugs (106 of 22 different species). As a remark, it was particularly interesting to find a hydroid bush with a Dondice banyulensis and lots of Flabellina affinis hanging from the branches, it was a authentic underwater christmas tree.

We went back to the shore and decided to grab a bite to eat. We went to the fisherman's tavern (or whatever it is called) and had some squid, Marc and Toni didn't need their compasses to find the food but they still took those with them and joke around, so we had some laughs. During lunch we could go over the pictures and everybody got a chance to look at all the species we saw during our first dive and talk a little bit about how hard it was to find them, how colourful they were, and the fact that sometimes there is so much to see down there that is just there but we never look hard enough to find it.

After lunch we set off for our second dive, we were thinking about changing location but at the end we threw ourselves again at Punta del Romaní, this time all together though. We started the dive on a nice wall and then went on to the bottom. In this one, a Chromodoris luteorosea honoured us with its presence, and since it was the jewel of the dive we spent some time admiring it. Two other nice additions to our list during this dive were a Facelina annulicornis and a small Limacia clavigera, this last one cleverly spotted during picture post-processing by Toni.

This is the full list of the opisthobranchs species found during the course:

Species                          morning afternoon

1 Aplysia parvula                         3      0
2 Bosellia mimetica                 1      0
3 Calmella cavolini                 3      1

4 Caloria elegans                         3      0

5 Chromodoris luteorosea         0      1

6 Cratena peregrina               15      5

7 Cuthona caerulea                 5      2

8 Diaphorodoris papillata         2      0

9 Dondice banyulensis                 1      0

10 Doto floridicola                         0      3

11 Elysia timida                         6      2

12 Elysia viridis                         8      7

13 Facelina annulicornis                 0      1

14 Facelina rubrovittata                 3      1

15 Favorinus branchialis                 5      1

16 Flabellina affinis                       30          20

17 Flabellina babai                  1      0

18 Flabellina ischitana                 0      2

19 Flabellina pedata                 1      2

20 Hypselodoris tricolor                 5      1

21 Hypselodoris villafranca         3      1

22 Limacia clavigera                 0      1

23 Onchidoris pusilla                 0      1

24 Peltodoris atromaculata         4      3

25 Placida dendritica                 1      3

26 Thuridilla hopei                         2      0

27 Tritonia nilsodhneri                 1      1

28 Tylodina perversa                 3      0

        Total specimen      106         59

        Total species                22         21

In summary we had a good time with the people at Kenna ecodiving and hope they enjoyed the course and the dives as much as we did. Hopefully this is only the beginning of a long lasting relationship between the groups and the first of many more joint dives to come. It was a pleasure guys.

Happy bubbles,

Cheers, Miguel.