I did a little ‘recon’ last Sunday in beautiful St. Agnes on the north coast but my timing was a bit off (the tide came in, with sediment getting suspended and the water becoming super-oxygenated, resulting in lots of bubbles on the wetlens). Luckily, this Thursday with no wind, the sun out and low tide, I had the opportunity to nip out again: awesome! Trevaunance Cove has a small beach, with rock pools on either side, I chose the Trevellas Cove side. Coincidentally, Shoresearch Cornwall (facebook here and here) had a survey and so caught up with Matt and Adele as well as Thomas from HydroMotion Media who I had not seen in a while. The north coast is quite different from the south coast I am used too: more exposed and this site for instance had none of the long Thong weed and Wireweed which dominate Castle Beach. The pools are also wider and in parts have a rocky, gravelly or sandy bottom. One spot had a considerable rock overhang, and I probably spent a full hour alone just at these six meters or so as there was so much to see. With the tide out, it was only about half a meter deep, with rocks encrusted in purple corraline algae, pink and orange sponges, bryozoans, tunicates and red seaweeds. The over-under shot is not particularly great but gives a rough impression, as do the two underwater shots (note the mysis shrimp in the last photo): There is a great diversity in red seaweeds, but I find these species quite hard to ID. The red rags Dilsea carnosa look pretty ‘ragged’ in Falmouth at the moment, but in this shaded, high wave energy spot they looked very fresh (first photo). I made a lot more photos but I was really struggling, as the bright sun reflected on the sand, with the seaweeds sticking out from the shaded overhang, such as Sea beach Delesseria sanguinea. The third photo give a good impression of the beauty of this habitat. Black scour weed and Discoid fork weed manage to scrape around in the shifting sands. Serrated wrack hangs and drips from the rocks into the pools below.Apart from the mysis shrimp in the water column, very large prawns patrol the rock surfaces and Edible crabs, Velvet crabs and Spiny squat lobsters hide in crevices. The prawns are curious and really beautiful. Most spectacularly, I found a large lobster in a cavity and at one point had a small lobster walking over to me: Many fish could be spotted as well: Topknots are common (you can just about see one glued to the rocks behind the lobster in the photo above) and there were a couple of big fat Tompot blennies around as well. Dragonets patrol the sand and are very well camouflaged (and hard to approach). A juvenile fish was hiding on and in a sponge; I first thought it was a juvenile Black-faced blenny Tripterygion delaisi, but in subsequent facebook correspondence thought of a Montagu’s blenny Coryphoblennius galerita (very common here) but then settled on a little Tompot blenny Parablennius gattorugine. This would have been a very good subject for a proper macro-shot if only I could get to grips with my strobe! In general this was a great place and time for fish. Apart from the topknots, tompots and Montagu’s blennies (juveniles were abundant, present even in the tiniest pools), I saw sand eels, corkwing wrasse, a pollack and horse mackerel (both a bit lost in these shallow pools), corkwing wrasse, shannies, sand gobies and rock gobies. I thought I spotted a Giant goby, but this turned out to be a very large rock goby Gobius paganellus (thanks Matt Slater). After the large goby photo, a tiny Rock goby (I think), a Shanny, a Cushion star and Snakelocks anemones. I cannot wait to get back to this beautiful site, but will need to wait a bit for the next good tide…
It had been over two months since I last went snorkeling at my spot in Castle Beach. Although I did go on two boatdives (with no photos to show for), let’s say the work-life balance was tipped in the wrong direction. However I had time for a low-tide snorkel this Saturday and it was great to be back in the water, with a Curlew as my only companion. It was the plan to practise strobe photography but unfortunately I did not manage to get my settings right and I was going nowhere. As this is an activity that is supposed to be fun, I decided to ditch the strobe and stick with natural light. Fish I spotted were Ballan- and Corkwing wrasse, two-spot gobies, tompot blennies, a fifteenspined stickleback, a dragonet and sand eels: It is pretty much the worst time in the year for seaweeds but the pools are still quite pretty. The first three photos give a general impression of the seaweeds, including Thong weed, Harpoon weed and Irish moss. After that: Codium spp, Juicy whorl weed Chylocladia verticillata, a big plant of healthy-looking Hairy sand weed Cladostephus spongiosus, withered Red rags Dilsea carnosa and Dulse Palmaria palmata growing on a kelp stipe. I called it quits after two hours. On my way back I noticed an abundant green algae species I had not seen before. David Fenwick identified it as actually being a cyanobacterium rather than a seaweed: Rivularia bullata, interesting! Hope to do a lot more snorkeling before it gets too cold…
A quick post to keep the blog going. Seaweed season has passed me by a bit, first because of the bad weather and second, when the weather was better, because I did not have much time to go out. I went snorkelling only twice in May in my usual (shallow) spot at Castle Beach in Falmouth. On the 13th of May the plankton bloom was in full swing: a (wannabe) photographers nightmare! Generally, the seaweeds at this point were already a bit ‘over the hill’. I managed to get a nice shot of Berry wart Cress Sphaerococcus coronopifolius though (above). I also glimpsed what I believe is Iridescent Drachiella Drachiella spectabilis under a rock overhang. The bright blue Bushy rainbow wrack Cystoseira tamariscifolia contrasted very nciely with the deep red of the Red rags Dilsea carnosa, I hope to get a much better picture of that (probably next year…).By the next snorkel session the 19th, the visibility was much better. Some photos of the green seaweed Codium sp., A Gelidium sp. (pulchellum?) and a patch of Slender-beaded coral weed Jania rubens growing epiphytically on Hairy sponge weed Cladostephus spongiosus with the very common species Ulva and Oyster thief Colpomenia peregrina (and others). Next, Beautiful Fan weed Callophyllis laciniata and another Berry wart Cress Sphaerococcus coronopifolius. Finally, three shots giving a general impression of the seaweed growth and what I think is Chipolata weed Scytosiphon lomentaria as well as a snakelocks anemone inbetween yellowed False eyelash weed Calliblepharis jubata. About the animals: there are some juvenile pollack around, as well as two-spot gobies. I saw a brown, flabby shape drifting through the water at one point and my first thought was that it was a seahare but it actually turned out to be a small clingfish (I could not get a photo unfortunately). There were quite some polychaete worms erratically swimming around in their reproductive ‘epitoke’ stage. The final photo shows one (with a Nassarius reticulatus in the background) which could be Perinereis cultifera.
Last week when I was chasing whitebait off Castle Beach, I also took some photos of seaweeds. I have been taking photos of seaweeds at this same same spot every month this year (I have made a new tag 2017 Falmouth seaweeds, if you click that, you can easily track the changes back in time). Many species are dying off, so it is definitely not looking as pretty as in March or in April. Below some evidence of the decay: first Furbellows Saccorhiza polyschides covered in grazing Grey topshells Gibbula cineraria and second, discoloured Berry wart cress Sphaerococcus coronopifolius and Red rags Dilsea carnosa. Below some species that still look healthy: Bushy rainbow wrack Cystoseira tamariscifolia, Hairy sand weed Cladostephus spongiosus, Chipolataweed Scytosiphon lomentaria (not 100% sure!), Polysiphonia and Codium.
Less than 12 hours back in Cornwall and I managed to slide into the rock pools at Castle Beach in Falmouth this Saturday to see what the seaweeds looked like. There was a noticeable difference with only a week ago. The speed at which seaweeds grow, and decline, still amazes me. I managed to take my best photo yet, of Red rags Dilsea carnosa (surrounded by a whole bunch of other species), above. I made so many photos that I will split them over two posts, with some general ‘seaweeds scapes’ here and with individual species in the next post. The Sea lettuce Ulva has been taking over parts of the pools, turning it a bright green. The reds of the Juicy whorl weed and Berry wart cress and pink of Harpoon weed are less bright, and the Red grape weed and Fern weeds are turning ‘fuzzy’. Still, the seaweeds are much bigger and cover most of the seabed and it looks very exuberant. The Wire weed and the Thong weed (or ‘spaghetti weed’) Himanthalia elongata have been rapidly growing; the latter consisted of ‘buttons’ in January and are now a meter long, so must grow around a centimetre a day. The fronds are covered in flakes (which must be reproductive structures) that come off when you swim through them, clouding the water and so ruining the shot if you do not take it straight away. The sun came out more in the last photos, hence the different light (I have edited most (not all) photos slightly using standard Windows Photos, mainly by decreasing the highlights). More photos very soon!
A couple of weeks ago I went for a bit of a spur of the moment after-work dive with colleague Andrew (like me a quite unexperienced diver) and his friend Charlotte Sams. Charlie is an experienced diver and natural history photographer, who has her own blog: Charlottesamsphotography, which you should check out. We dove in Falmouth off Pendennis point. The water was not very clear (maybe 5-6 meters visibility) but the temperature was quite nice. We saw (amongst others) Sand eels (do not know which of the two species), Pollack Pollachius pollachius, Dragonets Callionymus lyra, Two-spotted gobies Gobiusculus flavescens, a Tompot blenny Parablennius pararugine, very large Ballan wrasse Labrus bergylta and a beautiful little John dory Zeus faber:
We also saw some very large Common starfish Asteria rubens and also a nice Spiny starfish Marthasteria glacialis. We dove only to about 5-7 meters, which meant we could stay in quite long, over an hour. At seven meters, the bottom was a sandy expanse, interspersed with mounts of Laminaria Kelp covered in hydroids. In-between the kelp were other seaweeds, such as Red rags Dilsea carnosa but I was more focused on the animals during the dive. In shallower water were enormous bundles of Wireweed Sargassum muticum (also known as japweed but that is not very pc…) and the very long slimy Mermaid’s tresses or Bootlace weed Chorda filum. Snakelocks anemones were very common, and we managed to also see Leach’s spider crab Inachus phalangium, which lives associated with these anemones. All in all a fantastic experience, and I hope to find the time to go diving very soon again!