A nice low tide at Falmouth’s Castle Beach today. The weather was not great but at least it was not raining (I still managed to get quite soaked, including my wallet…). Quite a lot of brittlestars, urchins, worm pipefish and porcelain crabs around. I did some collecting for the aquarium: beadlet and strawberry anemones, snails and urchins. Otherwise I focused on the smaller stuff and took pictures with the olloclip macrolens on my iPhone. First two tiny crustaceans that I have not attempted to identify and what I think is a tiny Edible crab Cancer pagurus. The nicest find was a white colonial tunicate that at very first sight looked like an eggmass. I could not readily identify it using the usual websites, so hope that the NE Atlantic Tunicates facebook page members can help me out (Note: they did, it could be a ‘regressed’ Diplosoma spongiforme). On Sunday I had a quick look in Flushing and for the first time found some juvenile Candy-striped flatworms Prostheceraeus vittatus (see here for adults), very pretty!
The winter season is the time for beachcombing and so I was very happy that Santa gave me The Essential Guide to Beachcombing and the Strandline; a fantastic guide to objects washed on British (and NW European) shores by Steve Trewhella and Julie Hatcher. One of the things that sets it apart from other guides is that it not only covers biological ‘objects’ (shells, fish, mermaid’s purses, sea beans etc) but also strandline debris of human origin (e.g. buoys and nurdles). After a walk at Praa Sands beach, it helped me to identify the Goose barnacle Lepas pectinata. A must-have book for anyone who likes to spend time on the beach! At Praa Sands I also found several Chama bivalves attached to a tangle of rope. David Fenwick has recently described three Chama species, all from (around) Florida (there are no native species), see here for much more detail. Unfortunately it is very difficult to tell what species it is from only the lower valve of the ‘Jewel Box’. It is interesting to see that even commonly encountered bits of rope and net can be from as far as the other side of the ocean. Hopefully there will be some westerly January storms to wash up more interesting species!
The weather has been awful lately (October in the UK, no surprise there) with lots of wind. A good time for some beach combing! I have not done much of that actually (here one old post) but hope to head out more over the winter. Last week a large piece of a space rocket washed up at the Isles off Scilly, but I am willing to settle for something less exciting… We headed for Chapel Porth Beach west of St. Agnes on the North Coast, a very rugged bit of coast. Because of the rain and the sand blasting, it was not very suitable for the kids so we stayed only for a very short while. Plastic debris high on the shore, some pieces of dead bird and a big buoy covered in Goose barnacles Lepas anatifera and potentially Lepas hilli (thanks David Fenwick); I find it difficult to distinguish between the two.A very large number of small Mauve stinger Pelagia noctiluca jellyfish had also washed up. I tried a couple of quick underwater photos but I should have taken a little more time to get them right. We then took the decision to head from the North coast to the South coast (which are only 25 miles apart), specifically Marazion at St. Michaels Mount. The weather can vary quite a bit locally and we figured it could only be better on the other side. The tide was still low and here the wind was onshore as well, however, not a single object seemed to have washed up. It kept raining and so we cut the beach combing short. Better luck next time!
The weather was not great last weekend and we were too late at the diveshop on Saturday to be back in time to get the tanks refilled for a dive on Sunday but the one dive was (as always) worth the effort! We took dive buddy Chris’s boat from Loe Beach in Feock over to the other side of the Fal Estuary (between St. Just and St. Mawes) to explore the Maerl beds. See an earlier post on a snorkel trip to see this bed of ‘Cornish coral’ for some more background information. After the usual faffing about with equipment on board we plunged in the water. I took a single photo of the boat which turned out quite dramatic:Although we were diving 1-2 hours before high water (the best time, as clear seawater is pushed in the estuary), the visibility was quite bad. After going just a couple of meters down, fields of maerl loomed into view (the dive was really shallow, 5.9 meters max I think!). There were quite a lot of Thornback ray Raya clavata egg cases (foreground first picture) but we did not see the rays themselves. There are two main Maerl genera around here, Phymatolithon and Lithothamnion but their growth forms are varied and there are other encrusting Pink paint weeds that could look similar. We saw a number of golf balls that were completely covered in coralline algae, quite cool.We saw a couple of *very well* camouflaged crabs sitting about. They were completely covered by sponges, coralline algae and seaweeds. There are a number of crab species shaped like this but most of them seem too small. Best guess is th
e Toad crab Hyas coarctatus the Europan spidercrab Maja squinado in a particular extravagant mood. There are lots of little things hiding in the Maerl; gobies (rock gobies I think), squat lobsters, swimming crabs, hooded prawns and things that hide faster than I can identify them. I noticed a dainty little prawn sitting about which is probably Thoralus cranchii, although it could also be Eualus occultus (second picture is cropped). Swimming crabs were common and probably mostly were the Harbour crab Liocarcinus depurator. The first picture was the only one with flash and shows the Maerl colours a bit better. The second photo shows a Velvet swimming crab Necora puber under a snakelocks anemone sitting on top of a bottle. This species can be very commonly seen rockpooling. Lastly an empty shell of the largest European sting winkle Ocenebra erinaceus I have seen so far and probably the largest sponge I have seen so far too (with a human head for scale).
After the success of last weeks snorkelling session, it was high time for a proper dive! Again the Helford did not disappoint. In the end, my Sea hare stroking proved a bit inconclusive; also, my estimate of 30 cm long individuals might have been a slight exaggeration, 20-25 cm is more likely for the larger individuals. My guess is that it might be Aplysia punctata after all, and perhaps this is just a very good year where they reach their maximum size. (Note that three individuals can be seen in the first photo and two in the second photo.)This was not the only Ophistobranch activity going on, as I spotted a small nudibranch sitting on the eelgrass. Probably Eubranchus farrani, although it could well be something that is deserving of a new name, there is a lot of (cryptic) species discovery and taxonomic revision ongoing in nudibranch biology. I also spotted several largish egg masses on the eelgrass that are likely to be from a larger, shelled Ophistobranch; I am waiting for suggestions from various facebook groups *could be Haminoea navicula*. I found a beautiful Wooden canoe bubble shell Scaphander lignarius, these animals live buried in the sand so are not commonly spotted. Next time I’ll bring a small garden rake to see what is hidden below the sand (I am serious!), lots of echinoderms and molluscs to be sure. Pelican’s foot shells Aporrhais pespelecani live in sand, but I found some on top of the sand too, so full of muck that they were barely recognizable. I have found empty shells of this species washed up on holidays before, but it was cool to see them alive for the first time.No cuttlefish in sight this time, but loads of eggs so it is likely that this is an important breeding ground for this species. We encountered one Thornback ray Raya clavata, which, like cuttlefish, are not very shy. These species occur in very shallow waters (we probably did not dive deeper than 7 meter) and the influence of the surrounding woodland is clear, with decaying oak leaves and pine cones amidst the seaweeds and eelgrass.One very well-camouflaged species is the Scorpion spider crab Inachus dorsettensis. Medium-sized Common hermit crabs Pagurus bernhardus are common, running around in Turban top shells covered with hydroids. Although present in the last post, another pic of a
Mud sagartia Sagartia troglodytes anemone Red speckled anemone Anthopleuris ballii. Filterfeeding worms are abundant too, including the beautiful Fan worm Myxicola infundibulum as well as a large tube-dwelling worm and worms in white calcareous tubes with bright red bristles that I could not identify. As we got out of the water, we saw a Comb jelly Beroe cucumis, very pretty but hard to photograph. The next dive will have to wait two weeks or so, but then I hope to finally play around with my GoPro.
I have previously posted about exploring the more muddy sites in Flushing’s Penryn River and also about catching fish with a net from the quay (here and here). This weekend had a good tide and I decided to combine the two by climbing down from the quay with my net. No blue water and clear, colourful rock pools but black mud, waste from fishing boats and in general a lot of crap, not a pretty sight/site! Mussels and (native) oysters, rock gobies, fan worms and estuary sponge are common here. Lifting one piece of waste, i found a juvenile Eel Anguilla anguilla, which was impossible to grab and place into my cuvette for a proper photograph. One cool find were bundles of squid eggs (no idea about the species). I also found tangles of the sponge Sycon ciliatum, which before I had only seen as individuals hanging from seaweeds (see here). Also visible are some Leucosolenia botryoides sponges.There was a heap of discarded scallop shells; I noticed they were covered by large Balanus balanus barnacles as well as the soft coral Dead man’s fingers Alcyonium digitatum (I had never seen this before but this could only be one thing!). The lower parts of the quaysides were covered in estuary and breadcrumb sponges and especially in droopy Morchellium (or Aplidium?) sea squirts. Although generally an ‘ugly’ habitat with lots of waste to boot, still plenty of interesting finds.
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….
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.
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.
On to some of the more tricky species to identify. The rock overhangs, the home of the Painted top shells, are covered in sponges, tunicates and bryozoans. These are organisms I need to spend some more time on, as they are diverse, pretty and easy to photograph (they do not scurry away or give any macro depth-of-field problems). First two pictures of the large, nicely textured sponge Ophlispongia papilla. After that, the cream-coloured sponge Dysidea fragilis and the yellow sponge Aplysilla sulfurea. Side-by-side the bryozoan Disporella hispidata and what might be the sponge Clathrina coriacea.
There were quite a lot of other sponges and bryozoans to see as well, so I’ll definitely investigate more the next low tide. Some other species: the tiny polychaete worm Euphrosine foliosa (first two pics). Next, Chaetopterus variopedatus, a quite large polychaete worm (thanks to David Fenwick for the ID), a tiny glossy bivalve Kellia suborbicularis (thanks to David again) and what is probably a Chameleon prawn Hippolyte varians.
I made some pics last weekend when low tide wasn’t very low, but since this weekend the tides hit record lows I will first post about these finds. First up, the sheltered estuarine conditions in Penryn river in Flushing, opposite Falmouth’s port. The conditions are silty, with lots of sponges, tunicates, variegated scallops, sea lemons, European cowries and enormous amounts of Squat lobsters (see also this old post). With the tide this low, we were able to see some other stuff as well. The water went as low as the Eelgrass:Shannys, Rock gobies, Rockling, Worm pipefish and (to a lesser extent) Butterfish are easy to find in Flushing. Today we saw for the first time two Connemara clingfish Lepadogaster candollei (first pic). Next a Rock goby Gobius paganellus. We also saw many large Tompot blennies Parablennius gattorugine which live subtidally and only now could be seen: