Friday a week ago I helped out colleagues to collect speciments for the rock pool exhibits of the annual Science in the Square event here in Falmouth. Leaving the house at 05:45 was ‘not ideal’ but seeing Gylly beach lie serenely in the early morning sun this was immediately forgotten. Low tide was not very low at all, and so it was a bit of a struggle to find animals. In the end a variety of crabs, fish and other critters could be collected. I managed to catch a Compass jellyfish and haul it from one end of the beach to the other in a full bucket of water thinking this would be a unique addition, only to find out that five others were already caught. The one really cool find was a little shark stuck in a rock pool. It was a Nursehound Scyliorhinus stellaris, also known as the Large-spotted dogfish, Greater spotted dogfish or Bull huss (distinguishable by the frilly nasal flaps from the smaller species the Small-spotted catshark Scyliorhinus canicula). (Its eggs can be frequently found here, see for instance these older posts.) It was quite dark and hissed a little bit. Way too big to bring back and so it was happily set free. 
Tag Archives: Bull huss
photographing seaweeds with a Canon Powershot part V
I have been a bit busy and so the photos below are some weeks old. The seaweeds are in decline already it seems. Actually, that is not true, there are plenty of seaweeds growing, but some of the prettier ones are dying off and some of the uglier ones are taking over. The window to take the nicest rock pool shots is quite short, pretty much early spring only. The ubiquitous False eyelash weed Calliblepharis jubata is yellowing, the green Sea lettuce Ulva lactuca is starting to cover everything and the Red grape weed is getting ‘fluffy’. Not the best session photo quality-wise and probably the last of the year. The Bushy rainbow wrack Cystoseira tamariscifolia is abundant and looking good (on the photo with Discoid forkweed Polyides rotundus) and I managed I nice shot of young Thong (or Spaghetti) weed Himanthalia elongata. I have done some more research into ‘proper’ underwater cameras and was tipped of about the Canon G16 (thanks Thomas from HydroMotion Media), maybe something for next year….
The past couple of times when focusing on the seaweeds I also encountered some animals (it is hard not to). Many Snakelocks anemones Anemonia viridis, with some having very short tentacles. Next, a Decorator crab Macropodia rostrata covered in Banded pincer weed Ceramium. Mermaid’s purses (egg cases) of the Bull huss/Greater-spotted Dogfish/Large-spotted Catshark/Nursehound Scyliorhinus stellaris seem to be exclusively attached to Bushy rainbow wrack. Finally, a Stalked jellyfish Haliclystus octoradiatus on Wireweed Sargassum muticum.
photographing seaweeds with a Canon Powershot part II
This friday, I tried my hand at some more underwater rock pool photography with my point-and-shoot Canon Powershot (see also here and here). This is both rewarding as the colours of seaweeds are so vivid and the textures so varied, and frustrating, as I cannot use the viewfinder and even if I could, lots of shots would be much better using a wider-angle lens. Also, I am often kicking up silt with my wellies and the nicest shots often are just out of reach. So next time, I should really photograph whilst snorkelling. (It would be great to use an SLR in an underwaterhousing. I bought a much cheaper and much more cumbersome ‘underwater-camera bag‘ without remembering that my old, not-so-frequently-used-anymore Canon EOS 400D does not have a viewfinder. I am afraid this will make the experience less, not more, fun…) Anyway, the trick for now is to take many pics and hope some turn out all right. I like the ones with a water surface reflection best. The nicest one was a snakelocks anemone among corraline algae. Next, what is may or may not be Sea flax weed Stypocaulon scoparium. After that, the brown Divided net weed Dictyota dichotoma growing inbetween Discoid fork weed Polyides rotundus, a Bull huss/Nursehound/Large-spotted dogfish Scyliorhinus stellaris mermaid’s purse and a Spiny starfish Marthasterias glacialis. Probably more photos soon as the pools look by far the best in early spring.
A superlow tide at St. Michael’s Mount
The lowest tide of the century so far, on a Saturday, with beautiful weather and on a stunning location: what could go wrong? Very little! St. Michael’s Mount, Marazion, Mount’s Bay is one of the most beautiful spots in Cornwall and an excellent site for rock pooling with a mixture of eelgrass beds, rocks and sandy expanses. I felt like a kid in a candy shop: wanting to turn every stone, photograph every seaweed and inspect every gully before the tide would come back in. I needed to collect some more Clawed fork weed Furcellaria lumbricalis for a cool student project. That was abundant so easy to sort. Chock full of Pheasant shells Tricolia pullus. One other amazing thing was that the place was littered with Bull huss Scyliorhinus stellaris (a.k.a. Nursehound, a.k.a. Large-spotted dogfish) mermaids purses. Mount’s bay is an important breeding ground for these sharks. The yolk was easy to spot, but the embryo’s still to small to be seen. There were loads of pretty seaweeds gently waving among the eelgrass in the crystal clear water. I saw a bright green Chameleon prawn swimming about, but the picture I took was a bit underwhelming. 
I had met up with David Fenwick, so could get all species identified on the spot. Very striking was a great amount of small, fuzzy pink seaweed balls: Falkenbergia, the tetrasporophyte stage of the Harpoon weed Asparagopsis armata (it looks so different from the gametophyte stage, see some old posts, that it was long considered a separate species). Also, a picture of Bushy rainbow wrack Cystoseira tamariscifolia, simply because one cannot post too many pictures of Bushy rainbow wrack….
Some invertebrates: the large scale worm Alentia gelatinosa, a Strawberry worm Eupolymnia nebulosa larger still, a tiny hermit crab Anapagurus hyndmanni and the Arctic cowrie Trivia arctica:
The find of the day (the month probably) was a Little cuttlefish Sepiola atlantica. This picture is crap, but David has made some stunning photos back in his lab and they will appear sometime soon on his aphotomarine site I am sure.
a very low tide at Falmouth part 1
Low tides over the weekend, see the previous post for the trip on Saturday in Flushing. On Sunday the wind resulted in the water being swept up quite high on the shore unfortunately (the next very good tide I will make sure to check the wind a bit better, probably would have been a good idea to have gone to the north coast). Also the rain made swiping my iPhone very difficult and I was absolutely drenched. Luckily I had already taken a long lunch break on Friday when it was sunny! As I found a good number of species I will divide them up over two short posts instead of a very long one. In this post some species that have featured before, but that I now have taken better pictures of: a Shore clingfish (or Cornish sucker) Lepadogaster lepadogaster, a particularly purple Spiny starfish Marthasterias glacialis, a particularly orange Painted topshell Calliostoma zizyphinum as well as a close-up of the ‘normal’ colour variety, Blue-rayed limpets Helcion pellucidum, Seven-armed starfish Luidia ciliaris and a Bull huss (Nursehound shark) Scyliorhinus stellaris mermaids purse. Nice colours all around:
taking my iPhone underwater
Two weeks ago I went snorkeling with colleague Chris (his hands can be seen in a picture in the previous post) as we figured making a pact would speed up the process of getting in the water. Spring has been so-so and sticking your head beneath the surface was a bit painful but in the end we stayed in for 45 minutes or so. Unfortunately the visibility was very bad. The sea was almost like a soup: you could feel the algae streaming down your face. However, lots of small jellyfish could be seen and occasionally a wrasse darting off. In slightly deeper water, the seaweeds were dominated by Oarweed or Tangle Laminaria digitata. Seaweed diversity seemed much higher in the shallows and the bright light green of the Sea lettuce, the pink of the Harpoon weed and the blue of the Bushy rainbow wrack looked quite amazing. Last week I went back by myself during a lunch break with the audacious plan of taking some underwater pictures with my iPhone. There are quite a lot of (cheap) underwater housings for iPhones nowadays of which I had bought one recently (the ‘amphibian waterproof case’). I tried it out holding it under a tap with distilled water (if it would leak there would not be any damaging salts at least) and that seemed to work. I later saw a patch of moisture but this was minimal condensation that did not seem to any harm. The case:
The water seemed quite a bit less cold the second time around and the visibility was slightly better as well. However, Castle beach is exposed and the wave action results in a lot of debris (such as pieces of dead seaweed). Also, it seemed that some of the seaweeds were already ‘over the hill’; the Harpoon weed often seemed discolored for instance and not that pretty anymore. I have noticed the proliferation and die back of some seaweeds before and it makes sense that there is some seasonal succession (I will keep tabs on the growth of the different species month-by-month in an excel spreadsheet). It should have come as no surprise that my plan of taking crisp, brightly colored underwater pictures with my iPhone in a flimsy case turned out to result in blurry, out of focus and badly composed shots, but it was still a bit disappointing. Some of the least crap ones:
It was quite neat to sea mermaids purses (ray or shark egg cases): bright white and fat (i.e. alive) instead of the black and empty wrinkled ones you find on the beach. I have no idea what species they are but they seemed relatively common and I only found them attached to my favorite, the Bushy rainbow wrack Cystoseira tamariscifolia. *edit, most probably eggs of the Nursehound (or Bull huss) Scyliorhinus stellaris.* I also tried some quick shots in the rock pools as the water is more clear there, but the pictures did not turn out to be too great in there either:
Although quite cheap and -knock on wood- safe, the iPhone case is not a substitute for a real underwater camera. All pictures turned out quite hazy (although this was certainly also due to the bad water conditions). At times it is hard to operate the touch pad and there isn’t a cord to attach it to your wrist which makes the experience a bit less relaxed. I have a Panasonic Lumix that can go 10 meters deep and an old Canon Powershot with an underwater housing which seem to do better (although neither of them in turn can be compared to a SLR in an underwater housing). I will try to explicitly compare some shots with these cameras soon. Next time I go snorkeling I will also try a less exposed spot where visibility will hopefully be better.
An Bollenessor 