I had the pleasure to go on two dives with Mark Milburn of Atlantic Scuba on the ‘Stingray’ RHIB this weekend and last, leaving from Mylor Harbour (see photo above). The first dive was in the Helford Pool, a deep area in the otherwise shallow Helford river. Buddied up with Sue and Al, we descended to 18 meters to swim over a gravelly area covered with tunicates and sponges. This was a drift dive but we did not get all the way to the eastern end of the pool where some small maerl beds are located. Swimming crabs and Leach’s spider crabs were very common; there were not many fish though. One exception was a cute little John Dory Zeus faber. I was struggling to take any decent photographs, in part because I have not used my strobe much yet and because I should have two, not just one! Sue Barnes kindly let me use a photo she took of the John Dory for the blog; also added is a photo of a sponge, one of the few half-decent ones I managed to take:
The dive today took us to the cannon ball site, roughly a mile from Pendennis Castle, and an area where many of the cannon balls fired for practice ended up. With buddy Alex we descended to around 16 m using a shot line. Again a flat ‘rubbly’ area with few fish. The seafloor was covered with Common brittlestars Ophiotrix fragilis. The viz was quite good, and it was much lighter than the previous dive. I also had *a bit* more luck with the strobe. Leach’s spider crabs were common, and we also saw some Sea lemons, Doris pseudoargus, a large seaslug. 
Up next three common species: a little Rock goby Gobius paganellus, the colonial Antenna hydroid Nemertesia antennina and the colonial sea squirt Aplidium elegans (thanks David Fenwick). I keep my eyes open for seaweeds too of course, there were some small red species and what I suspect is Desmarest’s prickly weed Desmarestia aculeata. I found out back on the boat that I completely missed a small octopus that Alex pointed out, argh! I was very happy though that I managed to spot an Imperial anemone Capnea sanguinea, which is an uncommon species. The photo of this all-white individual was taken without a strobe; I really should have taken more time to get a decent shot. A good reason to go back though, and maybe we can spot some cannon balls then too. The water is 13-14 degrees and so it is still doable to dive with a wetsuit. 
Category Archives: hydroids
a brief beach comb at Sandy Acres Beach
Sunday was a beautiful spring day and we headed out to a new spot: Sandy Acres Beach on St. Ives Bay, North Cornwall. Beautiful dunes and a vast beach with very few people on it! With the kids running amok, I had only very little time to scour the high tide strand line. However, even with only 50 meters or so covered, it was the best bit of beach combing so far. Many cuttlefish bones, bits of Horn wracka and quite large mussels covered in seaweed holdfasts. Below a quick snap. At the bottom, I am not 100% sure, two Thornback ray Raja clavata- a Spotted ray Raja montagui and just above that a tiny Small-spotted catshark Scyliorhinus canicula mermaid’s purses (egg cases, see here for a useful key). Next to the mussel Mytilus edulis, some Hornwrack Flustra foliacea (a Bryozoan), two sponges which might be Mermaids glove and Chocolate finger sponge (thanks Steve Trewhella at the Beachcombing facebook group) and a spiky piece of Sea beard Nemertesia antennina, a hydroid. At the right of that a piece of a whelk Buccinum undatum egg cluster (better pic here). Not a bad haul, looking forward for a proper walk along this beach very soon!
Leftover Pics
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).
Oaten Pipes Hydroid
Another small post. I went out to the marina in Mylor Harbour to check what the pontoons looked like. It turned out OK-ish but no Peacock worms and only a few little Plumose anemones. However, the trip was worth it solely by the find of a hydroid colony, which my Seasearch guide told me was the Oaten pipes hydroid Tubularia indivisa. Very pretty! By taking 30 photos with my Canon Powershot, I ensured I had a couple in focus. Also in the frame some little Sycon ciliatum sponges (these are a lot more rounded than some of the others I have seen, see here). 
More Pontooning
Went back today for some more peering from the pontoons in Mylor Bridge marina. Besides the Thicklipped mullet and Two-spotted gobies, small schools of Sand smelt Atherina presbyter were out and about. A short clip of this silvery, pretty fish made using the Canon Powershot 30D and after that a clip made with a GoPro 3+ (not in HD as it was my 2nd, free upload)):
(Annoying that wordpress makes the 2nd clip smaller!) I managed to find back the single 1 cm Elegant anemone Sagartia elegans mentioned in the last post but again was unable to remove it; seems like this species knowns how to attach itself a bit better than do Plumose anemones. I noticed that besides the tunicates, sponges, bivalves (mussels and oysters), seaweeds, anemones and peacock worms, hydroids and bryozoans are also very abundant. I still have to educate myself a bit about these groups. The peacock worms would be beautiful for the aquarium. Although they would be easy to dislodge, it would be problematic to fasten them to something again. Maybe I’ll find a small object with some attached when I’m diving that I could take back some time (frozen artemia might be too big for them to eat, so I would need to look at artifical plankton products for food).
An Bollenessor 