The Hair Curler Seaslug (Spurilla neapolitana) is a southern species that was first discovered in Cornwall by @charlotte.cumming last year. It has quickly established itself as one of the most common species found here in Falmouth. As always I was a little bit late to the party spotting this nudibranch but lately they have become hard to miss! This species feeds on anemones using their radular teeth and can easily be found at the base of Snakelocks anemones. The stinging cells of their prey are neatly incorporated into their own curly cerata. I found baby slugs as well and this species is clearly here to stay. What will this explosion of new predators mean for the anemones? Will Snakelocks populations collapse before antipredation mutations appear? Or perhaps it is not such a problem for them, we will find out!
The weather is slowly taking a turn for the worse now, so if there is a window to get in the water I am ready for it (I am absolutely dreading the coming half year of wind, rain, darkness and no snorkelling or diving!). Last weekend I took a look underwater in my local seagrass patch in Flushing. The viz was not great at all (as anticipated), so I was looking to do some macrophotography. I clocked plenty of egg masses and indeed some Polycera quadrilineata, which is one of the more common species here in Cornwall but up there with the prettiest! Individuals of this species are often white with yellow stripes and dots, but they can have black lines as well. After taking ages reviewing shots full of backscatter and re-positioning my strobe, the photos started to work out. I noticed one blade of seagrass with two individuals side by side. I suspected they were mating but as they are quite small and my eyesight is getting worse, the anatomical action that was going one only became apparent reviewing the photos back on land. Nudibranchs are simultaneous hermaphrodites and when they mate act both in the female and male role. In the pics below you can see the sexual organs protruding from their right flank. Interesting!
I was on a roll and I pretty much stayed the entire dive on the same square meter, taking photo after photo of the slugs around me. I follow the ‘spray and pray’ routine of photography to make sure at least some of the pics are in perfect focus and without overblown highlights, although the downside of this method is that you have to wade through 200+ pics afterwards. Using the nauticam cmc-1 wetlens I managed to get ‘supermacro’ and was rewarded with some really nice head shots, showing oral flaps, foraging on bryozoans on the seagrass and the slugs generally being very pretty! I am getting more and more into nudibranchs now and hope to find some other species before the sea turns too choppy!
P.S. The previous post was all about low depth of field images; for the photos in this post I took the opposite approach and used the smallest aperture available.
Apologies for the title, but this is what this post is about: snorkelling in one meter of water taking soft focus images. Low depth of field (DoF) results from a large (or wide) aperture (somewhat confusingly, to make the aperture larger you need to select a lower f-number on your camera). A wider aperture results in more light hitting the sensor, so it is something you’d do when taking photos under low light, but it can also be used for creative effects, as it results in only a thin slice of the image being in focus. This leaves cluttered backgrounds and foregrounds blurred out which makes for a more pleasing aesthetic effect. I used this technique for the photos above and below of a European Cowrie (Trivia monacha) (M43: f4, 1/160s, ISO100). Of course there is a trade-off: most of the subject is out of focus, so it is not a setting you would use for an ID shot that needs as much detail as possible. The golden rule is to keep the eye(s) in focus – something that worked slightly better in the second pic. Strangely, this snail has two pupils in its right eye! I have indicated the slice that is in focus in the second photo with a red line; the shell is 10-15mm in length.
While I was taking photo after photo of this snail, I was approached by several small Tompot Blennies. This species (as well as Common Blennies, but not so much Montagu’s Blennies) is very curious which is great for a photographer (although sometimes they come too close and you have to keep moving back). I used the same settings as above for the smallest individual (not longer than 4 cm). I noticed for the first time the blue spots on the dorsal fin (see first pic). I did not get THE photo but it was good practice. Finally, a close-up of a baby Topknot; although the aperture was smaller this time, the mouth is still not in focus. Sorry for all the photography talk if you are not into that, but at least I hope you enjoyed the pictures!
High time for a quick update. Spring has not started in earnest yet and so the number of days in the water have been limited. As is usual, I have practiced taking pics of Flat Periwinkles (Littorina obtusata or L. fabialis) on a bank of the Penryn River. Below that another set of pics taken in Flushing and Falmouth when it was too windy and choppy to get in the water. These were all taken with my cygnustech diffuser which give the pictures a quite distinctive, slightly subdued look.
I did go in the water a few days in a row when the weather and tides allowed it, which was great. I think one time I stayed in for three hours – my core temperature took some time to recover! No special finds and only a few good pics as my strobe placement had become quite rusty but here are the best and/or the most interesting ones. (Species names in the photo captions.) Bring on proper spring weather and flat seas!
I had a couple of good snorkels at the end of summer in the seagrass beds off my local beach in Flushing. The water at the end of summer is warm enough to go without wetsuit – I just had a weightbelt to let me sink down on the sand at low tide, no fins needed. I managed to do what I normally find very difficult: spot nudibranchs! Mainly one of the more common species, Polycera quadrilineata, but that was fine by me, as they are very beautiful, especially the black colour morph pictured above. I spotted one other species, the egg-eating Favorinus branchialis (with its own eggs also visible). Not great photos, but in my defense they are very small!
Shelled molluscs are easier to find. Below 1) the ubiquitous Grey Topshell Steromphala cinerarea, 2) the Grooved Topshell Jujubinus striatus and 3) the tiny Rissoa membranacea (faecal pellets on show, even within the shell). The latter two species are strongly associated with seagrass.
Some assorted macro photos below and at the end a view at a very low tide of the Flushing seagrass site this October.
A quick post with some finds from a recent walk on the shores of Flushing, specifically above-water (‘topside’) macro shots with a diffuser. This always leads to my subjects turning out with subdued grey and brown tones, but that is OK. A velvet crab, the amphipod Cymodoce truncata (looks a bit like a trilobite!), a worm pipefish covered in a film of water with some more shots (with descriptions) at the end.
A few weeks back I drove to one of the UKs more well-known divesites, Porthkerris, about 50 minutes away, for two dives. I had only been there once before, also for two dives (not worth going all the way for just the one) when I did my PADI Advanced Open Water (I just realised that I forgot to blog about that at the time…). The pebbly shore here leads to the Drawna Rocks and it is one of the few places in Cornwall that a shoredive can get you a bit deeper than 10 meters (maybe 18 at a high tide). This allows me to see some critters that are not present at my usual haunt Silver Steps in Falmouth. One example is the North Sea Tube Anemone (Synarachnactis lloydii) above. The black pebbles are quite striking, and also a very different background then what I am used to. For the first dive I took my macro lens, as it was quite choppy, and my expectations of the viz were low (which turned out to be correct!). I practiced a bit on the Jewel Anemones (Corynactis viridis) which come in a range of beautiful colours: orange, yellow, pink, white and green. I also took a shot of a Devonshire Cupcoral (Caryophyllia smithii) which is a solitary hard coral and some detail of a boring sponge (Cliona celata), including Rissoa parva snails I later noticed (they are everywhere in the rockpools too).
For the second dive I took my weird probe lens to bother some of the Spiny Lobsters (Palinurus elegans). Finally, a Cottonspinner (Holothuria forskali), what a beaut!
A trip to one of my favourite spots on the North Coast, Booby’s Bay, two weekends back led to a fun rockpool photography sesh. The pools here are quite different than in Falmouth: deeper, more exposed and with fewer seaweeds (see here for impressions). Shannies (Common Blennies) and Montagu’s Blennies are abundant here and I chose not to seach for things ‘more special’ but take pics of these characterful fish. Shannies are greyish and common, but actually very beautiful as you can see above. Their mottled, slimy (scale-less) skin also makes them very well-camouflaged as is clear from the photo below. Below a few more pics, including of Montagu’s Blennies, which have a ‘quiff’. Some of these fish have hatched not too long ago and are tiny (<1 cm)! When I took these pics the weather was great (and I ditched the wetsuit) but as I am writing this post it is raining and blowing outside. My snorkel outings will be less frequent from now on unfortunately, but on the plus side my blogging will pick up….
There was little wind last Saturday and a superlow tide so time for some rockpool macro! Above, a Purple Topshell Calliostoma zizyphinum; common but and pretty. I liked the background which was achieved using a relatively shallow depth of field (f/8). I took my time exploring a small patch (core body temperature slowly decreasing) as this is the only way to find creatures that are smaller than topshells. I spotted a St. John’s Stalked Jellyfish Calvadosia cruxmelitensis and took the same shallow depth of field approach (f/5.6). Lastly a pretty little mollusc: the White Tortoiseshell Limpet Tectura virginea. (It is only about half a centimetre long, so I had to use my CMC-1 wetlens for extra magnification.) This species is found on calcified red seaweeds on which it grazes. Their colouration is amazing (I especially like that the growing edge of the shell looks very different). Similar-sized Blue-rayed Limpets (see this recent post) are much more often photographed than this species – what can I say, Tortoiseshell Limpets are the hipster’s choice!
I have a lot more pics from this year to put on the blog but those have to wait, as I want to post some photos from last Saturday first, when there was little wind, a low tide and some sun! The viz was not great as expected, so I brought the macrolens and went in search for some small critters. No special finds, but I was very happy with my shots of a common little mollusc the European Cowrie (Trivia monacha). Most people will be familiar with this species as beach finds of empty shells, but not know how it looks like when it is alive, when its mantle covers most of the shell, it shows its striped tail at the back and a siphon and cute little eyes at the front. I used a shallow depth of field (f/4) to get rid of the ugly cluttered background, which worked well if I may say so myself (I need to try this technique more often!).
Many other critters were found too and I took shots of a selection. First, a Sea Spider, all legs and crawling away. A tiny mat of colonial tunicate that looked like a persian rug on drugs. A quick shot of the ubiquitous (if you know where to look – on kelp fronds) blue-rayed Limpets and a stalked jellyfish. Finally, I spent a lot of time taking shallow-depth-of-field AND slow shutter-speed photos of a scorpion spider crab in a snakelocks anemone to get some sort of ‘artistic’ shot. It did not really work, but it was fun nonetheless and I will have a go at it again. After almost 2,5 hours in the water I stumbled back to the car to get changed – an afternoon well-spent!
