Although St. Martins does not seem to have any rockpools, the beach that was nearest to us (called ‘Lawrences’) has a stretch of rocks lying on the sand that can be turned over at low tide, and so we did! A nice find was a small Sevenarmed Starfish Luidia ciliaris (these can grow up to half a meter across, although you will not find them that size in rockpools). We also found a Bootlace Worm Lineus longissimus, which is (probably) the longest animal on the planet. These nermertean worms secrete a powerful toxin in their mucus, but luckily for us it affects arthropods and not mammals. They are not very rare btw, I see them here in Flushing and Falmouth too. It was about 5 meters long (without stretching it), but they can grow ten times the size of this! In the second photo you can see it in its natural habitat, under a rock, with some photobombing crabs and worm pipefish. Another cool find was a juvenile Conger Eel Conger conger. Otherwise we found the usual suspects, lots of crabs and a bunch of fish, see for a small selection below.
The wind has picked up and will ruin any chances of getting good seaweed shots this week. Too bad, but what can you do? A bit of rockpooling I guess. I took my son out to our local beach in Flushing where the rocks gently slope into Penryn River. Although there are no ‘proper’ rockpools, low tide gives access to a mixture of maerl sand and rocks that can be turned over. It is silty and definitely not very pretty, but there is always something to find. It was an especially good weekend for finding fish, seeing Shannies, Tompot blennies, Rock gobies, Gunnels, Worm Pipefish, Shore Rocklings and a tiny Eel, as well as Sea Scorpion eggs. (One Shanny was quite big and proceeded to bite my son’s hand; he was very brave and we slowly put it back.)
Invertebrates were plentiful too. The main mollusc here is the Variegated Scallop Chlamys varia, which is attached underneath every single rock. We found our smallest Great Scallop Pecten maximus as well. We found some Sea lemons Archidoris pseudoargus and lots of Yellow-plumed Sea slugs Berthella plumula (which apparently can secrete sulphuric acid when disturbed…). A small selection of what we found below, all pics taken with an Iphone.
Some pics from today at Flushing Beach. Above, a pair of Green shore crabs Carcinus maenas, below two Furrowed crabs Xantho hydrophilus. (I probably should have gone for a whole crab series, as I saw several other common species…) Instead I took loads of random photos, of things that were 150 mm to things that were only 5 mm, with varying success. For instance of a Painted Topshell Calliostoma zizyphinum on the invasive Bryozoan Watersipora subatra. Also the underside of the urchin Psammechinus miliaris, showing its mouth (Aristotle’s Lantern). Photobombing top left is the commensal worm Flabelligera affinis (which I noticed as well the last time I took a version of this picture). Bit random but it was fun practicing. It actually is more difficult to take photos abovewater compared to underwater due to the glistening and the awkward position kneeling on wet gravel/rocks. Next time I might try a tripod (ideally remote flash would be used but I do not think I am going to invest in that). Btw, if you are on instagram, I also post pics as @an_bollenessor.
Another quick, brisk trip to the rocky shore in my village of Flushing today to practice my macro photography with the 60mm lens. I used the highest F-stop, varied the output of the flash and let the camera decide the shutterspeed and ISO. I did not find anything too special, but the very common organisms are just as pretty as the rarer species. Above and below juveniles of the Flat topshell Gibbula umbilicalis and the Grey topshell Gibbula cineraria on pink encrusting algae. Still not quite used to not having optical zoom as with my old Canon Powershot but quite happy with the shots, especially as all were hand-held. As I am lazy, these are JPEGs with some tweaking using Windows photoviewer.
Below a Black-footed limpet Patella depressa, a more ‘atmospheric’ shot of a periwinkle, might be the ‘normal’ Littorina littorea but not 100% sure, and a baby Edible crab Cancer pagurus. Really looking forward to go into the water again, but not only is it still cold and grey, it is very windy and choppy so bad viz. Probably another rockpooling post next weekend!
It has been three months since the last blog post so high time for an update. I have not been out much as the weather has been grim. In fact, the photos in this post are one year old! I bought a blue LED light for fluorescence photography which has been gaining popularity in recent years. Many organisms and fluoresce (i.e. absorb light and emit it at a longer wavelength), although the function of this is generally not well-understood (perhaps in some cases it might not even have a function and just be a byproduct). Coral reefs can especially be spectacularly fluorescent but the cold waters of the UK harbour a variety of fluorescent organisms too, most notably anemones and corals, see here for great marine fluorescence photos from Scotland by James Lynott. Anyway, I bought my light and a yellow barrier filter (which serves to let the emitted fluorescent light through but not the blue light) to be held in front of the camera housing, as well as a headset barrier filter from a very knowledgable German chap here; his site contains a lot useful information for those interested in the background and applications of this type of photography (see also here, here and here). The photography is very tricky: the ISO needs to be bumped up in the dark which results in a lot of noise. The dark also requires long shutterspeeds which results in shaky images. A large aperture for more light is best, but since the subjects are usually small this results in suboptimal depth of field. I have only been out twice last January, and only whilst rockpooling (I have not done a single nightdive or nightsnorkel in Cornwall and I am not overly tempted to do so!). The very shallow rockpools high up at Castle Beach in Falmouth reveal some fluorescent animals, including hermit crabs but I focused on anemones. Snakelocks are big and very fluorescent (the green ones, the grey variety is not, although it does emit red light via its symbionts) but not common high up the shore. Hardly visible normally due to their small size and inconspicous colours, red-speckled anemones, daisy anemones and gem anemones become apparent using a blue light (in fact, this method is use to study tiny coral recruits in the tropics). The top photo shows two green gem anemones Aulactinia verrucosa (with red and purple coralline algae in the background). The anemones are very small (2 cm max) and I used my CMC-1 wetlens on my Canon G16. The other two photos show Daisy anemones Cereus pedunculatus. I only later noticed the tiny anemone babies (this is a livebearing species). I hope when the rain and wind disappear and the evenings still start early to go out again and post some more photos. Also, I have bought both a new camera and a new aquarium so I have plenty more to post about!
I have not been tempted to go back snorkeling yet, but had an hour of nice rockpooling last Saturday, at beautiful Carne Beach on the Roseland Peninsula. I had been here only once before, and found my first stalked jellyfish then. The stalked jellies (Haliclystus octoradiatus) where still there, in different colours: brown, yellow and grey (I will keep to my resolution to record my findings from now on, when I find the time). My old trusted iPhone 4S finally gave up the ghost last week so I upgraded to an iPhone SE which proved a real upgrade. (I was too lazy to bring out the Canon G16 in the underwaterhousing, which would not have been much use anyway as the pools here are very shallow.) The pools were teeming with (mating) polychaete worms and there were many juvenile Sea hares about as well. I saw whole mats of pink wriggling tentacles sticking out of the sand, something I had never seen before. These (most likely) belong to the worm Cirriformia tentaculata, quickly identified by David Fenwick, see here for very good photos of the whole animal on his aphotomarine site in addition to the rather bad snap here. I found a hermit crab inhabiting the shell of a (juvenile) pelican’s foot Aporrhais pespelecani, a species that shares the sandy beach with the razor clams that were washed up all around. The highlight for me were the anemones. Snakelocks and strawberries were common, and in addition to red Beadlet anemones, there were green ones as well (I never see these in Falmouth). Some pools at the edge of the rocks and the beach were filled with Daisy-, Gem- and Dahlia anemones. I am ready for some more seaside adventures, but the weather is rarely cooperating these days. More on the blog soon I hope!