What friends predicted happened last Sunday morning: someone scrambled down the rocks to check if this figure lying motionless in a shallow pool was dead or alive. Luckily, I was feeling very alive indeed, watching a sizable Spiny starfish Marthasterias glacialis moving over the rocks using its hydraulic tube feet. A beautiful blue-grey colour, the surface of these animals are very richly textured. I am not sure exactly what is going on at the tips of the arms: the very end shows a red organ, potentially light sensing. It is surrounded by nodules, which might be the precursors of the centres of new plates covering its body, or something else. The tube feet at the tips are smaller and orange-tinged and I am again not sure whether they are just newly developing or having special sensory functions. I noticed the madreporite at the top of the animal: this sieve plate is involved in pumping the water in the body for hydraulic locomotion. It resembles a stony coral ‘madrepore’ colony, hence its name. In general, the seastar surface resembles a coral I think. The photos are nice, but I know I could do a lot better: next time! 
Tag Archives: snorkel
The plankton bloom has arrived….
A sneaky worktime dive today: the weather was beautiful, sunny and windstill and the tide was great. However, unfortunately the water was one turbid mass of snot: the spring plankton bloom has started! It was impossible to take good photos; with a fisheye you can get very close to the subject (CFWA ‘CloseFocusWideAngle’) minimising the amount of snot between subject and lens, but this only works up to a point! I had a go anyway. The seaweeds are in decline as well, see the fuzziness of the iridescent Osmundea truncata above. Below some shots of my alltime favourite the spectacularly iridescent Bushy rainbow wrack Cystoseira tamariscifolia: 
Finally, the species Gelidium attenuatum (?), a common, thin and shiny species I would like to know the identity of, a rock with lots of buttons of Himanthalia elongata and a Snakelocks anemone amidst the Harpoonweed. Not sure when the bloom will be over, but I think I won’t bother going back over the weekend!
Some more seaweeds
Last Friday I went for another very shallow dip at Castle Beach in Falmouth. Even though the weather was pretty abysmal, it was definitely worth it! Here a small selection of photos, again the quality is not top notch but many pretty species to see. The first pic below shows the Hairy sandweed Cladostephus spongiosus remnants the Slender-beaded coral weed Jania rubens featured in the last post tend to attach to. After that, some Chylocladia verticillata, Dumontia contorta with Grateloupia turutura (past its prime) in the background, Heterosiphonia plumosa under a small overhang, a thin red (Rhodophyllis irvineorum? awaiting comments on the Seaweeds of the NE Atlantic facebook group) and finally Chondrus crispus and Dictyota dichotoma. 
first snorkel with the Olympus
Yesterday I finally took my new camera underwater! I should have gone a bit sooner, but too be fair the water has not been looking very clear (and the viz was still not ideal). The sun was shining and it was great to be back in the water (perhaps 12C, not too cold with a wetsuit). It should be a great experience to shoot with a new, better camera, but it ended up being a bit of a frustrating experience not finding the right settings (I know, first-world problems!). I was stuck in Aperture Priority mode, which was a problem with significant wave action and the need for a fast shutterspeed. Although I took close to 200 photo’s, only a handful were halfway decent. Still, I learned a lot for next time. I took the 8mm fish-eye lens which allows you to get very close to the subject (especially useful for water that is not crystal clear) and still get a wide angle view. Above, a photo of an estuary sponge and seaweeds as well as Snell’s window. Below a badly composed shot of seaweeds, a downward shot of Furcellaria lumbricalis seaweed and Bushy rainbow wrack with Spaghetti weed in the background. All not very sharp and with flat colours, and hopefully standing in stark contrast to the next batch of photo’s!
An Bollenessor 