This Sunday we went on a lovely walk from Helford Village to St. Anthony in Meneage on the south coast of the Helford river. The tide was very low, so we decided to follow the mud flats for a bit before heading to the woodlands. The mud flats are a brown-grey and strewn with shells, pebbels and, unfortunately, litter. Not as pretty as the rock pools, but still interesting. There were small banks with mussels, cockels, slipper limpets and oysters, both the native oyster Ostrea edulis (quite some juveniles) as well as the invasive Pacific (or Portuguese) oyster Magallana gigas. Of course also the abundant, barnacle-covered periwinkles Littorina litorea. I saw my first Auger shell Turritella communis (which does not reflect rarity at all, just the fact that I usually stick to rocky shores); the small shells around it are Needle whelks Bittium reticulatum. Finally a Chinaman’s hat (probably no longer the prefered nomenclature!?) Calyptraea chinensis.We met up with David Fenwick and partner-in-crime Carol who were busy sampling around Treath. David’s interest was caught by a mooring rope covered in seasquirts, and a boxful was collected for careful examination under the microscope later. The clump I am holding below shows the Compass seasquirt Asterocarpa humilis (red, middle) (invasive), Morchellium argus (orange, top) (native), the Dirty seasquirt Ascidiella aspersa (three grey ones) (native) and the Creeping seasquirt Perophora japonica (tiny yellow zoids connected by stolons growing over the Ascidiella) (invasive). Astonishingly, by the next day, in a single tupperware box filled with muddy seasquirts, David had found 70 species! (With 142 species recorded in total on the day.) To finish this post full of grey blobs and brownish molluscs, I am adding photos David made of four out of nine species of Heterobranchs (Nudibranchs ‘proper’ as well as Ophistobranchs) present in the sample. Stunning images and proof that there is tremendous biodiversity to be found on a muddy bank if you know how to look for it. More of David’s nudibranch work is featured in this old post. See for his continously expanding collection of images, from seaweeds to fish and from tiny marine fungi to stranded seaturtles, aphotomarine.com.
Last week I was on holiday in Bretagne (Brittany), France. There was not a lot of opportunity for snorkelling or rock pooling activities, but the last day I checked out the pontoons of the large marina in Trinité-sur-Mer. I was not disappointed; the pontoons in Cornwall are full of life, but these ones 200 or so kilometers further south were exceptionally diverse. The most striking find was that of orange, red and purple Rosy feather stars Antedon bifida. These also occur in the UK but I had not seen these yet here so I was quite excited. I did not go into the water myself and the photos I took holding my camera under ended up being not great so I took some shots from above water as well, too bad I did not have more time!The first photo below gives a good impression of how abundant and diverse life attached to these pontoons is. Many species are the same as the ones I see in Mylor marina, including invasive species such as the Bryozoan Bugula neritina and the tunicate Styela clavata. In addition to the many sponges, anemones, mussels, oysters and colonial tunicates I even saw things such as scallops (not sure which species) and urchins (Psammechinus). The peacock worms were absolutely huge. The plumose anemones Metridium senile looked different to the ones I am used to here to with orange individuals having brown collars which sometimes were really big and wavy. It seems no one that moors their boat in a marina ever takes notice of what is attached to the pontoons, but they should, as the diversity and beauty can almost rival coral reefs. I hope I can go back one time to properly investigate but for now I will check out the local marina’s and keep an eye out for feather stars…
Finally, time for a (solo)dive last Saturday, at probably the most accessible local site: Silver Steps in Falmouth (you can just make out the steps in the photo above). The sun and high tide had attracted quite a lot of other divers too, including University of Exeter and Falmouth University students learning the ropes. I was very keen to get in the water and take photos but my approach is probably not the best: I just shoot whatever happens to be in front of me. Better results could be obtained to specifically look for macro subjects, to stay in the water column and search for jellies, befriend the Ballan wrasse or stay put in front of a Leopard-spotted goby hide-out (or check out seaweeds of course). I’ll do one of these things next time, for now, some random shots. I spotted several Spider crabs; these are always shy and try to quickly retreat, except for one. This big crab came after me as soon as we spotted each other. I should have tried more shots, as unfortunately he did not fit the frame. You can see in the short movie why I didn’t!
The viz was not great (I find it hard to estimate it in meters though). In the water I noticed a small hydrozoan Leuckartia octona. The underside of some wreckage harboured Light bulb sea squirts (see previous post) and some were predated on by Candy striped flatworm Prostheceraeus vittatus. (I brought my new LED light with me to help bring some colour out but I just ended up with combinations of glare and shadows so stuck to my normal natural light pics.) Next, a curious Ballan wrasse Labrus bergylta. Finally, some not so clear shots that nevertheless give a good impression of how tall the invasive Wireweed Sargassum muticum are growing. Hopefully more dive posts soon!
Blogging slowed down a bit recently due to (variously or simultaniously) bad weather, work, bugs or unavailability of dive buddies. I entered one of the better photos I made this year (from this post) in the BBC Wildlife Magazine competition for fun and managed to get it published in the May issue, which was nice. I think I only went out once, which was a pontoon excursion in Mylor marina, the first time with the Canon G16. I tried some shots from above lying on the pontoon; I need to actually get in the water to get a better view of all the sponges, tunicates, peacock worms, mussels, oysters, anemones and seaweeds encrusting it. This shot of the Light bulb sea squirt Clavelina lepadiformis turned out best, but I believe there is a lot of room for improvement. I have bought a light which I will bring next time. I also ordered a strobe, so hopefully some proper dive photos very soon!
I recently posted my first photos taken with the nauticam CMC macro wetlens using stalked jellyfish as a subject. I since lost my lens, which I in large part blame on the bad fit of the adapter with which it is attached to the housing. The best thing in these cases is not to agonize over it too much, order a new one straight away and keep going, so that is what I did (also I am now a bit more careful of course). Here some more photos of macro subjects. Above a very easy subject as it is very common this time of year and also it does not move….Paddle worm egg capsules (probably Eulalia viridis). The individual eggs can be just made out in the gelatinous blob. Below, one of the more common nudibranch species Polycera quadrilineata. Nudibranchs come in all kinds of stunning colour variations and are very species rich and so are a favourite of macro photographers (see this old post hunting for them with David Fenwick in Newlyn, and check out the NE Atlantic Nudibranch facebook page for lots of eye candy). Tricky with the narrow depth of field to get the whole animal in focus. Mysid shrimp are quite common and beautiful little animals hovering about in small groups. They need dissection to determine which species it is, but this might be Leptomysis lingvura (around 10 mm). Finally, the colonial star Ascidian Botryllus schlosseri; these form colonies (‘systems’) where zooids have individual inhalant openings and a shared exhalant opening. They are common, sessile, flat, and come in a range of colours so they make ideal subjects for a beginning macro photographer. Not only that, apart from fish they are our closest relatives in rock pools, which is most obvious in the tadpole-like larvae which have a dorsal notochord (a cartilage rod functioning as a backbone). I hope to devote a post to them later in the year.
More photography practice lately. I have started to use Photoshop to post-process images, which is hard. I have sat with Thomas Daguerre for a session which was very helpful. For some images, the twiddling is of not much use; the image above of a Bull huss egg case for instance I am pretty happy with as is. Below I have pasted some before and after-Photoshop photo’s. Mostly adjusting highlights and contrast, cropping and playing around with sharpness (in the RAW files), most images tend to be a bit reddish. I have not bothered to tackle the ‘marine snow’ with the Spot Healing brush tool. First, Snakelocks anemones, next, Cocks’ comb Plocamium, then Harpoonweed Asparagopsis armata and an old kelp holdfast covered in feeding Grey topshells Gibbula cineraria. On and under the seaweeds I encounter many interesting tiny animals, but it is hard to take good photo’s without a macrolens. I have pasted a couple photo’s below (none have been edited in any way): the Stalked jellyfish Haliclystus octoradiatus (these can also be reddish or brownish, and can be found on a wide variety of seaweeds), a sponge, a juvenile Snakelocks anemone Anemonia viridis (next to a Flat top shell Gibbula umbilicalis) and the Star ascidian Botryllus schlosseri where I later noticed the fecal pellets underneath. Pooping tunicates, that is what we need more pictures of!Finally, some more before- and after- Photoshop images. The first is the nudibranch Rostanga rubra (‘Red doris’) which was only 5mm or so (see also the tiny Daisy anemone in the background). I shot it today, very cold: 4 degrees, and the water might have been only 8 degrees, brrrr! Next, a closeup of the seaweed Osmundea (see the first photo of this post) which shows its interesting pigmentation. The photo’s are nothing special yet, but I notice I am making progress. Excitingly, I just have ordered a macro wetlens and so hope to get some proper macro photography going soon!
A nice low tide at Falmouth’s Castle Beach today. The weather was not great but at least it was not raining (I still managed to get quite soaked, including my wallet…). Quite a lot of brittlestars, urchins, worm pipefish and porcelain crabs around. I did some collecting for the aquarium: beadlet and strawberry anemones, snails and urchins. Otherwise I focused on the smaller stuff and took pictures with the olloclip macrolens on my iPhone. First two tiny crustaceans that I have not attempted to identify and what I think is a tiny Edible crab Cancer pagurus. The nicest find was a white colonial tunicate that at very first sight looked like an eggmass. I could not readily identify it using the usual websites, so hope that the NE Atlantic Tunicates facebook page members can help me out (Note: they did, it could be a ‘regressed’ Diplosoma spongiforme). On Sunday I had a quick look in Flushing and for the first time found some juvenile Candy-striped flatworms Prostheceraeus vittatus (see here for adults), very pretty!
Last weekend I went down to Gylly Beach in Falmouth for a bit of rock pooling. However, the tide was not very low (especially with the inshore wind) and the weather was crap. Moreover, I could not find anything that I had not seen many times before; although rock pool life is very biodiverse, there have started to be dimishing returns when looking for non-microscopic organisms. Clambering over yet another rock, I decided to stop and play around with my Canon Powershot instead. I focused on a tiny pool (around two by four feet) completely covered in corraline algae. It does not look like much but taking the time for a carefully look was really rewarding. It is tricky to take photographs without being able to see the viewfinder though. My strategy has been to just take loads of pictures and hope some of them work out. The miniature underwater landscape was really beautiful. Pink plates Mesophyllum lichenoides made up the largest proportion of corraline algae (some bearing ‘reproductive conceptacles’). Another species is Corallina officinalis or Common coral weed (third photo). I had some Corallina growing in my aquarium at some point, but it grew very slowly and has now disappeared. Being able to create the right conditions for coralline algae to thrive in a coldwater aquarium would be fantastic, but I have not seen any evidence of anyone being able to cover their aquarium in them yet. (I have tried ‘planting’ Corallina and although it looked very nice at first (fifth pic), these seaweeds quickly died off, turning orange and then white (second pic).)Some other seaweed species were present as well; Irish moss and Harpoonweed (not pictured), False eyelash weed Calliblepharis jubata occurred in multiple patches, Rhodophyllis divaricata?, an Osmundea species and Red grape weed Gastroclonium ovatum. There were also a few brown seaweeds, the characteristic Thong (or Spaghetti) weed Himanthalia elongata buttons and the invasive (and pervasive) Wireweed Sargassum muticum. I did not spot too many animals, although I am sure there is an enormous hidden diversity present among the seaweeds. I noticed a red-white Dahlia anemone Urticina felina as well as some patches of a colonial brown tunicate. I’d like to go back soon and take some more pictures, with my Canon powershot or with my GoPro. I have an SLR as well that I have not been using lately as my iPhone is such a good camera and hassle-free. SLR underwater housings are really expensive, but I recently discovered that there are quite cheap waterproof SLR bags available which might be an option to try to take higher quality photos (in rock pools, I would not go diving or snorkeling with them). It would be very cool to try to make panorama pictures of rock pools, especially when taking one each month in the same spot to capture seasonality. More seaweed photos, Canon powershot or otherwise, to follow soon!
In the series ‘pontooning‘, I returned to Mylor a week ago Friday to have a quick look around in the marina. The water was choppy, but visibility on the sheltered side of the pontoons was OK. I noticed a brown slug-like thing flapping about next to a boat. My first thought was a sea hare (I have seen plenty but have not yet seen them swimming). Upon closer inspection, I saw that it was something else, it had a shell like Haminoea or Akera, species I had never seen, especially not swimming. It turns out that it was Akera bullata, an Ophistobranch mollusc that is rarely seen in Cornwall and generally is observed crawling on the mud, not swimming. Why they swim is not well understood, but they usually swarm in numbers and so there must be some general response to the environment or mating behaviour going on. I saw four other individuals nearby so that fits. I made a couple of movies but as I could not look through the viewfinder the footage is not great (I went back Saturday and Sunday to try and find them back but was not able to). The shell can be clearly seen hanging down (Akera is related to the Sea hare but has retained its external shell). When lifted out of the water, the animal folds its mantle around its shell.
There were some other interesting things to see. The dominant organism on the pontoons is the tunicate Cione intestinalis (I see there are some other tunicate species hiding in these pictures; I will have to take a closer look next time). Amongst it grows the purple invasive Bryozoan Bugula neritina. Next, a colonial tunicate thta could be Botrylloides violaceus, Trididemnum cereum or Didemnun maculosum (or something else again). After that, the beautiful Lightbulb sea squirt Clavelina lepadiformis.Plumose anemones Metridium senile are always common here. I for the first time noticed another species Diadumene cincta, very pretty!
The aquarium was in desperate need of a make-over (again…). I hauled a ton of rocks over from the beach and stacked them up. (I thought at first that I would need something to stick the rocks together (epoxy, superglue or waterfall foam) but that wasn’t really necessary). I also removed most of the gravel and replaced it with sand. So quite a big change but it really looks a lot better. However, my nice burrowing Red-speckled anemones suffered a bit when putting the sand in, and even after siphoning it off again I could not really find them anymore….hopefully they turn up again! The aquarium is still a bit bare and I have to go out and collect things that will live on the rocks, such as anemones and seaweeds. However, there is some progress on the seaweed front. There is a bit of Irish moss Chondrus crispus growing spontaneosly from the back wall. There are also some patches of pink corraline algae; which must be Coral weed Corralina officinalis judging from one outgrowing patch. Having this species grow would be great, but they do not seem like fast growers. Chrysymenia wrighti is still thriving on the circulation pump; I remove a bit every now and then, so it acts as an ‘algae scrubber’, removing nutrients from the water. I have placed a couple of other seaweeds in the aquarium, a bit risky as they can die off and start trouble, but I can’t help it. The red Soliera chordalis below has done well before but unfortunately has started to die off a little already (first pic). I have a big piece of a flat red species that has started to grow from nowhere as well (second pic).One day, the aquarium was full of strings of Painted topshell eggs. I noticed when feeding a day later that the water was not very cold: I had forgotten to switch the pump/chiller back on two days previously! So the trick to breed this species is to increase the temperature, although I am not expecting much to happen with the eggs. Either the Thick-lipped or Netted dogwhelks are also occasionally sticking their egg masses to the glass. I placed a chunk of orange Estuarine sponge in the aquarium; this was devoured by Painted topshells and Cushion stars, so it is a good bit of live food to add. I had planted a little washed-up eelgrass plant to see if it would survive and indeed it has grown more roots. (If you want to try this yourself, please always use washed up plants and don’t dig out any, as eelgrass beds are vulnerable habitats.) It would be great to have a second tank dedicated to eelgrass….The little scallop is still happy (see close-up). I have added another filter feeder: a Leathery sea squirt Styela clavata. Butt-ugly, but that is actually fun too. I am trying it out as they are an invasive species and so probably pretty hardy. A Sting winkle seems to like it (but not eat it). I have never seen my two Sting winkles eat anything actually. They move about very slowly, but they have grown.Now the snakelocks anemones are gone, I have added some more fish. I have caught some juvenile Pollack Pollachius pollachius with my net. At first I caught ones that were less than an inch, but they did not survive. Of the six two-inch or so ones I caught, three dissappeared after one day, but the remaining three are going strong. Very nice looking fish! I also caught a little Tompot blenny Parablennius gattorugine (by hand at low tide). It is quite shy, but is increasingly showing itself. A beautiful little fish! I have one remaining Two-spotted goby. The Common goby is doing very well and eats from my hand. I think I’ll go for another little tompot, more Pollack and Two-spotted gobies. Ideally I would catch some Leopard-spotted gobies with a trap when diving, let’s see….The other fish I would like to have again is the Goldsinny wrasse: very pretty and not as nervous as Corkwing wrasse.