David Fenwick (Aphotomarine), Matt Slater (Shoresearch Cornwall) and Thomas Daguerre (HydroMotion Media) had all tipped me off about the elusive ‘Cave of Dreams’ at Pentire/Fistral Beach in Newquay. Recent posts by Cornish Rock Pools and The Marine Enthusiast reminded me of the stunning Scarlet and gold star coral Balanophyllia regia that live there and made me decide to drive all the way (well, it is a good 45 minutes) to the North Coast. I did not find the cave on two earlier visits (see this post from almost exactly one year ago), but today Thomas showed me exactly where it was. Cave is a big word, it is more of an overhang, and I don’t think I would have ever managed to discover it myself (you can find a photo of it behind the aphotomarine link). The corals are tiny, 5-10 mm in diameter, but there are many of them, in the low hundreds. Unlike most corals, this species relies solely on catching food with its tentacles, and it does not have algal symbionts (zooxanthellae) to provide energy from photosynthesis. Dark ‘caves’ with lots of waterflow are thus a good habitat for them. They look a bit like the tropical sun corals, who I was lucky to see in Hong Kong last year, and which are quite popular in the reef aquarium hobby. I had to carefully position myself on the rocks, dipping my camera in the water. It was too shallow to stick my head in, and I did not want to enter the water anyway, to prevent disturbing this widespread, but uncommon species. There were some interesting sponges (one of them Polymastia boletiformis) and red seaweeds, but I decided to only focus (no pun intended) on the corals. I was quite excited, this is definitely one of the most interesting species I have seen so far in Cornwall and I am sure that many people would be amazed to learn that corals live on our shores. I played around with my wide-angle lens, my new macro lens and took shots without the wet lenses. The light was low and I had to contort myself a bit but some of the shots turned out nice. The macro is still difficult, but maybe I might be expecting too much from the setup I have (without strobes). I hope to go back soon and try to get more photos, I would love to try an underwater panorama shot!
I now am the proud owner of a nauticam CMC wetlens. It arrived too late for my first encounter with a nudibranch this year, however, it came just in time for a proliferation of stalked jellyfish. These tiny (around one centimeter), sessile relatives of jellyfish are not very well-known, but seem to be getting more popular, see for some other recent finds the other local blogs Cornish Rock Pools and The Marine Enthusiast. To find them, you need to carefully scan seaweeds in rock pools (they are not very picky when it comes to which species they attach themselves to). The key resource for UK (European even) rock poolers is David Fenwick’s Stauromedusae website. Above, the most common species, the Spotted kaleidoscope jellyfish Haliclystus octoradiatus, recognizable by the primary tentacles or anchors (the white ‘balls’ inbetween the tentacles). Below, St. John’s stalked jellyfish Calvadosia cruxmelitensis, with a zoomed out photo and finger nail to give an idea of scale. Finally, two not so good photos of a third species Calvadosia campanulata taken above-water as these were located just below the surface. One more species can be found on mainland Cornwall (the Goblet stalked jellyfish Craterolophus convolvulus) and one on the Scillies (the Horned stalked jellyfish Lucernaria quadricornis, but who knows this species is also present on the mainland). So some more searching to do!
When going out rock pooling, I always take my iPhone and Canon Powershot (for underwater use) and take at least a couple of photos. Because of a lack of time, or because a single good photo is not enough for a new post, not everything ends up on the blog. Now I have some free time, I picked a couple of unused photos made this year that seem blog-worthy. First up, In realized only what I had found on the beach at St. Ives when leafing through the The Essential Guide to Beachcombing and the Strandline: a Seabeard! This hydroid, Nemertesia antennina, grows as stiff colonies protruding from a matted base and occasionally washes up on shore. It looks a bit plant-like; at the time I did not have the opportunity to have a closer look and just snapped a quick photo. Next a Lesser sandeel Ammodytes tobianus found at Gylly beach. I always see them when snorkeling or diving (see here) but this was a good opportunity to see one up close (I get excited when I spot a dead fish on the beach (see also here) and I am not afraid to admit it!). Following are two colour varieties of the Spiny starfish Marthasterias glacialis, a Common brittlestar Ophiothrix fragilis and a shot of an Aequorea forskalea (or maybe A. vitrina) jellyfish. Next the gastropod mollusc Chinaman’s hat Calyptraea chinensis. I went back to Mylor marina for some pontooning recently but not much was growing; the only thing that stood out was the luxuriant sponge growth (I am not sure of the species, perhaps Halichondria).And of course some seaweed pictures. By iPhone: Under tongue weed Hypoglossum hypoglossoides in Flushing, Black scour weed Ahnfeltia plicata in St. Agnes and a photo showing a variety of wracks all colonizing the same patch (Flushing): Serrated wrack Fucus serratus, Spiraled wrack Fucus spiralis, Bladderwrack Fucus vesiculosis and Egg wrack Ascophylum nodosum. Next some Canon Powershot underwater pics (see also this post and this one): a random rock pool picture of mostly decaying seaweed, a closeup of my favourite the Bushy rainbow wrack Cystoseira tamariscifolia and a shot of Wireweed Sargassum muticum that has completely taken over a pool. Finally an SLR photo of a rock pool at Gylly beach with large Cystoseira baccata plants (middle, Wireweed on the left).
Last weekend I went down to Gylly Beach in Falmouth for a bit of rock pooling. However, the tide was not very low (especially with the inshore wind) and the weather was crap. Moreover, I could not find anything that I had not seen many times before; although rock pool life is very biodiverse, there have started to be dimishing returns when looking for non-microscopic organisms. Clambering over yet another rock, I decided to stop and play around with my Canon Powershot instead. I focused on a tiny pool (around two by four feet) completely covered in corraline algae. It does not look like much but taking the time for a carefully look was really rewarding. It is tricky to take photographs without being able to see the viewfinder though. My strategy has been to just take loads of pictures and hope some of them work out. The miniature underwater landscape was really beautiful. Pink plates Mesophyllum lichenoides made up the largest proportion of corraline algae (some bearing ‘reproductive conceptacles’). Another species is Corallina officinalis or Common coral weed (third photo). I had some Corallina growing in my aquarium at some point, but it grew very slowly and has now disappeared. Being able to create the right conditions for coralline algae to thrive in a coldwater aquarium would be fantastic, but I have not seen any evidence of anyone being able to cover their aquarium in them yet. (I have tried ‘planting’ Corallina and although it looked very nice at first (fifth pic), these seaweeds quickly died off, turning orange and then white (second pic).)Some other seaweed species were present as well; Irish moss and Harpoonweed (not pictured), False eyelash weed Calliblepharis jubata occurred in multiple patches, Rhodophyllis divaricata?, an Osmundea species and Red grape weed Gastroclonium ovatum. There were also a few brown seaweeds, the characteristic Thong (or Spaghetti) weed Himanthalia elongata buttons and the invasive (and pervasive) Wireweed Sargassum muticum. I did not spot too many animals, although I am sure there is an enormous hidden diversity present among the seaweeds. I noticed a red-white Dahlia anemone Urticina felina as well as some patches of a colonial brown tunicate. I’d like to go back soon and take some more pictures, with my Canon powershot or with my GoPro. I have an SLR as well that I have not been using lately as my iPhone is such a good camera and hassle-free. SLR underwater housings are really expensive, but I recently discovered that there are quite cheap waterproof SLR bags available which might be an option to try to take higher quality photos (in rock pools, I would not go diving or snorkeling with them). It would be very cool to try to make panorama pictures of rock pools, especially when taking one each month in the same spot to capture seasonality. More seaweed photos, Canon powershot or otherwise, to follow soon!
Back at Carne Beach on the Roseland Peninsula. No time for a good rock pooling session, but a nice walk along the beach revealed some nice surprises. Amongst the Laver and Furbellows lay Common starfish, Pod razorshells, Striped venus, Banded wedge shells and Rayed trough shells. A first: the Masked crab Corystes cassivelaunus (a female): common offshore buried in the sand, and usually only seen when washed up dead on the shore as is the case here (next to it a Sea apple). Also a beautiful piece of Sea beach (or Sea oak? the margins seem not ruffled enough though…). Finally, a Barrel jellyfish Rhizostoma pulmo, remarkably firm and heavy. This is a small one, about 20 cm across; 40 cm is normal and occasionally they grow to more than a meter in diameter, making it the largest jellyfish species in British waters.
A trip to Carne Beach on the Roseland Peninsula, east of Porthscato and west of Nare Head. The beach is facing south and the sun was so bright that my iPhone pictures were all overexposed, but I’m not complaining in February! I did not have time to go rock pooling much longer than ten minutes, but in this time, I managed to find Stalked Jellyfish, as described in the previous post. Some very nice rock pools to the east of the beach (the pools to the west where the beach is called Pendower looked even better). On pretty much every Slender wart weed Gracilaria gracilis plant I found a Spotted kaleidoscope jellyfish Haliclystis octoradiatus (see stauromedusae.co.uk for all things stalked jellyfish). I also found a smaller, red species which David Fenwick ID’d as a Lucernariopsis campanulata (last two pictures). I will now keep my eyes out for these beautiful little creatures as their biology and distribution are not well-known and record my findings.