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…
This Thursday was only sunny, but also not windy, with a good low tide in the early afternoon, which meant I reserved a few hours to go to Tunnel/Castle/Gylly beach for some snorkelling. The photo above shows Gylly Beach, with the start of Swanpool lagoon behind it and the Lizard in the far distance. (I took this with my iPhone using a Hipstamatic filter; for more iPhone pics of Cornwall see cornwall_hipsta on instagram…). The water temperature was OK (9C?) but the viz was not as good as I hoped. The seaweeds are at their peak now and the pools looked very pretty. Not many fish, but I saw a small brown thing floating around which I first thought was Sea hare, but turned out to be a small (perhaps a Connemara) clingfish lazing about until it noticed me and bolted into the seaweeds. I carefully snorkelled in about half a meter of water, admiring the views and trying to take photos close-up (as the viz was not too good) with my wide angle wetlens. Below an above-water shot of some iridescent Bushy rainbow wrack Cystoseira tamariscifolia and the invasive red Bonnemaisonia hamifera (on the left). I need to go back studying photography basics. A main challenge is contrast. The pools have beautiful white sand, which result in hugely overexposed photos (or completely darkened subjects). I have come up with my own law, the Photography Frustration Index (PFI): the beauty of the subject (B) x the difficulty of capturing it (D). The PFI is very high in the case of seaweeds! Next: Bushy rainbow wrack under Thong weed, Purple claw weed Cystoclonium purpureum, Bushy berry wrack Cystoseira nodulosum covered with the epiphytes Asparagopsis (left) and Bonnemaisonia (right), Hairy sand weed Cladostephus spongiosus, Black scour weed Ahnfeltia plicata (you can see they grow in the sand and must be used to scouring) a ‘bouquet’ of different species (with a snakelocks anemone) and a last photo of a variety of species, including the common False eyelash weed Calliblepharis jubata. The tides and weather conditions are unfavourable the coming days but I hope to go snorkeling again end of the week!
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.
Coralline algae, pink and purple, feathery or encrusting, are a conspicuous part of the local rock pools. When viewed close up, even the crusts are not boring, as they reveal little stalks and holes forming reproductive structures. The above species could be Common pale paint weed Lithophyllum incrustans or Common purple paint weed Phytamoliton purpureum; it is hard to tell species apart and there are likely more species than the few described on websites or in books. In the third photo, the thinner crusts are probably Phymatolithon lenormandii. Only when looking at close-up photos it becomes apparent that juvenile limpets (Patella spp) and White tortoise shell limpets Tectura virginea are very common. Coralline algae are desirable in tropical reef aquariums, as they cover the brownish live rock in pretty colors. There are even special supplements for sale to promote their growth. They need low phosphates and sufficent calcium (as well as magnesium) to grow well, just as hard corals do. Good light helps, although there are also species that thrive under low light. I have a bit of coralline algae in my tank, but only in spots with high flow, so that seems important too. It might be a nice experiment to take a small tank, with a good light source and a decent pump (with rowaphos to keep phosphates down), and add some coralline algae-covered rocks to see what happens. Doing frequent 100% water changes will replenish calcium and magnesium, and not adding animals and food will keep nutrient levels minimal. With some interesting rock formations, it could develop into something pretty.The species Titanoderma pustulatum grows on other seaweeds, such as Irish moss Chondrus crispus on the photo above. Pink plates Mesophyllum lichenoides are coralline algae that are very common on the mid- and lower shore here in Falmouth. They look a bit like a miniature version of Montipora corals. At the moment, some individuals are covered in knobbly reproductive structures housing spores. Pink plates grows epiphytically on Common coral weed Corallina officinalis, the species that makes up the bulk of the coralline algae in the rock pools (see second photo of this post, on the right). Slender-beaded coral weed Jania rubens is also quite common at the moment. Corallina and Jania can be seen growing side by side in the second-last photo. Jania here grows epiphytically on Hairy sand weed Cladostephus spongiosus (this species is normally fuzzy but in winter the branches are bare and slender). I hope to go diving soon and take more photos of the most ‘spectacular’ coralline algae: maerl.
As I noticed that the rock pools have started to look really pretty, I have gone out snorkelling four times the last week to photograph seaweeds. Bitterly cold (around 10°C) but worth it! It is my aim to post photo’s taken at the same spot every month this year, let’s see. The first three days the tide was very low, making it more of a lying on the sand rather than actual snorkelling. The sun was out and my main challenge was to get to grips with overexposure, checking histograms and decreasing image brightness. The other main challenge is to not stir the sand up and create ‘marine snow’. It makes a world of difference to actually stick your head underwater and look through the viewfinder instead of lazily only submerging the camera. For now, I have only cropped and adjusted contrast of jpegs using Picasa, but I have also shot in raw format and hope to get more out of the shots in the near future. With help from the excellent Seasearch Guide to Seaweeds of Britain and Ireland and the Seaweeds of the NE Atlantic facebook page some of the species could be identified. Above, Osmundea osmunda (probably), which has a very nice blueish (‘glaucus’) tinge (I need to take some close-ups of that next time). In the following photo, a whole tangle of species, mainly Hairy sand weed Cladostephus spongiosus, with Osmundea, Asparagopsis, Bonnemaisonia and Leathesia. Next, another picture of a whole variety of species, I would like to find out what the red epiphyte is. Below some photos of individual species of red seaweeds (mostly not great but it gives an idea of the diversity). First, Leafy rose weed Rhodophyllis divaricata, next Falkenbergia (which is actually not a species but a distinct phase in the life cycle of Harpoonweed Asparagopsis Armata), Berry wart cress Sphaerococcus coronopifolius, Irish moss Chondrus crispus, Beautiful fan weed Callophyllis laciniata, Under tongue weed Hypoglossum hypoglossoides, Chondrus with Falkenbergia and Hypoglossum and Plocamium on top and a small unknown species. You can see that most photos suffer from overexposure (and notice my crude upped contrasts). The last time I went snorkelling, it was overcast and the tide was higher. I tried a bunch of shots a greater distance away to capture more of an overall impression, but with more water between the subject and the lens the shots become ‘milky’. The next shot of a whole variety of red, green and brown species (with Clawed fork weed Furcellaria lumbricalis in the middle) could have been really nice with clearer water, better framing and correct exposure! The next shot shows Cladostephus and Thong weed Himanthalia elongata on top of a rock covered with Red grape weed Gastroclonium ovatum (also on the last photo).
During this spring and summer I have taken my Canon Powershot 130D to the shore in addition to my iPhone. I have been trying to take underwater pictures of seaweeds with it, which is a bit of a challenge as (when you are not snorkelling) you usually have to take the photos ‘blind’. Some of ’em however turned out quite nice, here is a selection. I still find it hard to identify species. Here are some I do know. First, Hairy sand weed Cladostephus spongiosus. Second, a pool with many reds, in the foreground Discoid forkweed Polyides rotundus. Third, the invasive species Grateloupia turuturu. The big plants bleached and died off in summer but the young ones are growing already. Fourth, (probably) Sea flax weed Stypocaulon scoparium. I will post some more pics soon.