Buoy Biodiversity

A while ago I played around with taking pics of the underside of a buoy, which was fun, and so i wanted to practice this some more. My mistake the first time (see here) was to use a fast shutterspeed (the buoy was bobbing about after all) which made the water look unnaturally dark. I tried again this weekend and it went a bit better, although I already know I can improve things. This time I thought it would be nice to put some names to the amazing fouling biodiversity (I did this before for some seaweed images, see here). Crustaceans (tube-dwelling Jassa), Sponges, Bryozoans, Seaweeds but especially a lot of Tunicates (seasquirts; both solitary and colonial species). David Fenwick (of AphotoMarine fame) had a quick look to help with some IDs; there is a more there but this was not meant to be exhaustive. I have underlined species that are invasive. Anyway, I am sure I will post more of these types of images: the buoys are always there and these organisms do not swim off when you try to take a photo!

a Phyllodocid Worm

Had a nice snorkel yesterday; the weather was good and with the seaweeds growing I was tempted to go for the wide angle lens but in the end I was cautious and went for macro (where the visibility is not as important). Lots of stalked jellyfish and some nice chameleon prawns but I had trouble aiming the strobe right somehow. I turned over some rocks and found a large ‘worm ball’ wriggling frantically. It was hard to estimate its size but might have been 10-20 cm. It is a Phyllodocid worm, possibly this one. I also managed a closeup which really shows off the lovely green and blue colours.

Happy Holidays Everyone!

I realized this week that I have been blogging on my marine biology adventures for a decade now! Worth a quick self-congratulatory post surely. After living in landlocked places for years (in Germany, the UK and The Netherlands), the move to Cornwall rekindled my love for the seashore. I started this ‘nerd blog’ (with a name no one ever remembers!) shortly after as a way of documenting my adventures for myself, and the occasional stranger stumbling upon it. This had led to some unexpected opportunities, such as recently contributing to the second issue of the magazine ‘Fish – A literary celebration of scale and fin’ with a little piece on snorkeling in Cornwall. I can highly recommend this once-yearly magazine to anyone who is interested in fish – a true labour of love by Nathan Hill of Practical Fish Keeping fame (ahem). The blog topics have changed somewhat over the years, with less focus on rockpooling and my coldwater marine aquarium and more photography-based posts (you can click on specific tags in the cloud at the bottom of the page). The photography has improved (I hope), from using my iPhone and point and shoot camera to a much nicer Olympus micro four thirds camera. The shot above was my favourite from this year (see here for an explanation of what you are actually looking at). Thanks go out to my sister for touching it up in lightroom since (btw, if you are looking for ocean-themed jewellery, please check out her webshop laguna treasures). I think the Links page can still be useful to fellow enthusiasts, although I need to update it (this is for instance a great resource for coldwater marine tank keepers that needs to be added). Anyway, I’ll just say I hope to do a lot more underwater photography in the new year and post it on the blog!

Buoy

A rare sunny interval on Saturday meant I grabbed my gear for one last snorkel this year before returning to The Netherlands for Christmas. The visibility seemed good the last couple of days (judged by peering down the quay) and there was no wind, but I was quickly disappointed when sticking my head underwater at Flushing beach (also had major brain freeze!). I headed to the nearest buoy to practice some close focus wide able shots with my two strobes (one just arrive back from Japan for repairs). This proved difficult but fun. Lots of adjusting positions; outward when they created back scatter and inwards when the middle of the photo was not lit up. As the buoy was bobbing about I used a fast shutterspeed which resulted in dark water but that too has its charms. Lots of diversity, including the solitary seasquirt Cione intestinalis, colonial seasquirts Botryllus schlosseri, Diplosoma listerianum, Didemnum (maculosum?), bryozoans Watersipora subatra and Bugula and/or Bugulina species, the purse sponge Sycon ciliatum as well as tufts of red seaweeds and green Ulva. There are an enormous amount of tiny critters such as worms and snails hidden between all these species as well. It will be a nice project for next year to take a better wide able pic and complement these with macro pics of individual species.

Corals at Porth Mear Cove

I met up this Friday with Tom from Hydro Motion Media to look for Scarlet and gold star corals (Balanophyllia regia) in a cove that was new to me: Porth Mear, between Newquay and Padstow. It was a beautiful day, sunny and crisp, but with frost on the ground. Tom was keen to capture timelapse videos of feeding Snakelocks Anemones using his GoPro. (Follow him on instagram @hydromotionmedia to see his videos.) I was keen to get some photos of the beautiful yellow coral polyps. We met recently on Fistral Beach in Newquay to look at this species in the ‘Cave of Dreams’ (see here for an old post) but I did not get any good shots that time. Tom knew exactly where to find the corals in a shallow gully. These corals are solitary but they occur in small clusters. I saw several dozens of polyps; a few stood out by being fluorescent yellow instead of the normal orange and yellow. They are tricky to photograph, awkwardly located under overhangs and with an ugly greyish ‘animal turf’ for a background. The cove was very pretty and had some really good rock pools; I will definitely try to come back here!

Violet Sea Snail

An hour of beach combing today at Praa Sands, chosen because it is a reasonably long beach facing the prevailing wind that day. A fair amount of Goose Barnacles smattered among the rocks. On the strand line, bits of seaweed and lots of plastic rope fragments from fishing boats (which were duly picked up). Not expecting anything spectacular, my eye was caught by a tiny bit of violet, which proved to be a Violet Sea Snail! We had only found a Janthina janthina once before in our ten years in Cornwall but that was an empty shell whereas this still had its bubble raft. Janthina floats at the surface on the open ocean under this raft and therefore is part of the ‘neuston’ (or ‘pleuston’). It is a predator of other such purple ocean surface dwellers such as By-The-Wind Sailors Velella velella, and the Portuguese Man o’ War, Physalia physalis. It was tiny, the shell measuring only a centimeter or so. There were many By-The-Wind Sailors too, and these were just as small or smaller (usually they are 4-8 centimeters or so). I did not use a flash (looks to artificial), keeping ISO at 200 and f/7.1 I had to go down to 1/30s for shutter speed which was doable leaning on the beach. The protoconch is nice and sharp when you zoom in.

Macro Musings

Foul weather in Cornwall at the moment (it is November, so no surprise there!). Not tempted to go in the water but still wanted to take photos, so I spent some time on the foreshore of my village Flushing looking at Flat Periwinkles (Littorina obtusata). This species is very common, and the only snail that actively crawls about above the waterline. The trouble with macro photography is that with a small aperture, the depth of field is large and everything is in focus, but this includes the usually cluttered background that takes away from the subject. With a large aperture, it is possible to get an aesthetically pleasing, soft focus bokeh background, but the depth of field is much smaller, and too much of the subject is blurry (see the pic on the right). I tried my hand at focus stacking, in which the camera takes a bunch of photos each with a different part of the subject in focus, and then merges them so the depth of field is greater (whilst still having the out-of-focus background). This proved too difficult with a handheld camera (especially on my knees in seaweed). I therefore reverted to ‘normal’ manual photography and it was fun to practice. However, I did not manage to improve on my best Flat Periwinkle photo I took when I first got my Olympus….

St. Cuthbert’s Cave

Holywell Beach on the North Coast of Cornwall is known for a small sea cave which houses a ‘holy well’. According to Mabel Quiller-Couch, in her 1894 book “Ancient Holy Wells of Cornwall” in 995 AD the bishop of Lindisfarne, Aldhun, was bringing the remains of saint Cuthbert back to Ireland. Blown off course in a gale, he was left stranded in Cornwall where he settled and built a church dedicated to St Cuthbert. After some years however, an oracle instructed Aldhun to return the relics of St Cuthbert to Durham. As he was leaving from Holywell Bay, the saint’s bones touched the side of the well, giving the spring its magical healing powers. In medieval times, many people flocked to this cave to seek out the healing powers of the spring.

I was in the area this week when the tide was low (at high tide the cave is completely flooded, so you have to check the tides!) and decided to bring out the fisheye lens and a tripod to take some long exposure pics. They came out all right. There are more colourful photos available online, but my suspicion is that these use artificial light and sometimes also some enthusiastic post-processing. By using the longest possible exposure time on my camera (Olympus OMD E-M1markII), a full minute, I was able to let enough light into the camera. This enabled me to use f/18, allowing great depth of field, and ISO200, meaning little noise.

The formations result from a rare (in Cornwall) limestone deposit in the roof of the cave. Slightly acidic rainwater percolates through this limestone, dissolving calcite and becoming enriched in calcium bicarbonate. When the water drips down the rocks, the process is reversed and calcite precipitates, especially in areas where the water moves a little, causing CO2 to gas off. This results in the dam-like rimstone (or gours) formations. The tiny ‘rice terrace’-like formations on the dams are called microgours. I’d like to go back one time to experiment more and also to take some macro photos of the microgours and colourful microbes.

Miscellaneous Macro

I have not posted a lot this year; in part just because I have not been out as much as I hoped I would, and in part because I had some technical difficulties (I had to sent back a malfunctioning strobe and am also having snoot troubles). As a result I have not gone scuba diving and did not see much of the rock pools either. I managed to take some macro shots over summer though that are worth a quick post. Above a Cushion Star Asterina gibbosa on a colony of the star ascidian Botryllus schlosseri. Below one of my favourite little molluscs, the beautifully patterned White tortoiseshell limpet Tectura virginea. Another tiny mollusc, is the Needle Whelk Bittium reticulatum. The Variegated Scallop Chlamys varia is also common (under rocks) and can be nicely patterned when they are small. Finally some other tiny critters: the Flatworm Leptoplana tremellaris (I like their beady little eyes) and the Bryozoan Disporella hispida.