After half a year of strobe troubles (probably a mix of different faults, making it difficult to troubleshoot), I seem to finally have a working set-up again. Although the stalked jellyfish season passed me by, I am now raring to go. I went in today and yesterday and although I did not manage to spot any nudibranchs, there is always something to see. For instance, the White Tortoiseshell Limpet Tectura virginea above, which is very common on coralline algae. Below, the chiton Callochiton septemvalvis (stuck to the same rock as a week earlier), a tiny gastropod, probably Rissoa parva, a Cushion Star Asterina gibbosa, the Sea Ghurkin (a sea cucumber) Pawsonia saxicola and a baby squat lobster (<1 cm). There is currently a large influx of Crystal Jellies, which are not jellyfish but the medusa stage of hydrozoa. It probably is Aequorea vitrina. I have seen several being eaten by Snakelock anemones (slightly too large to take a good photo of with a macrolens). Below a detail. Finally, another, very different-looking, hydrozoan (I have to have a look at the biology of these things some time). It is Candelabrum cocksii, a species which was originally described based on specimens collected from this very beach. (I have posted a photo of this species before, but they look very blobby abovewater). The second pic is for scale. Hopefully a dive sometime soon!
I have not been in the water recently but went good oldfashioned rockpooling instead a week ago. No ‘lifers’ but there is always something interesting to see. For instance, my first albino cushion star (Asterina gibbosa). This small species (these individuals are only a little over a centimetre) is incredibly common here. Btw, I must confess this shot was staged, I placed these seastars together. Below, a Candy-striped flatworm (Prostheceraeus vittatus), also about a centimetre. Next, the Yellow-plumed or Side-gilled seaslug (Berthella plumula). Another common species but it is difficult to get a decent photo of this blob! This mollusc has an internal shell and, interestingly, glands that secrete sulphuric acid when it is attacked. You can see a little slug right beside it, maybe a juvenile Sea Lemon. Finally a photo that I had wanted to take for a while: can you spot the crabs? One of the most common invertebrates here is the Furrowed Crab or Montagu’s Crab Xantho incisus. Xantho species are known as Pebble Crabs which is the name I prefer; although highly variable in colouration they are very good at blending in amongst the pebbles! How many can you spot? There might be a stray Risso’s Crab Xantho pilipes in there as well, as they are quite similar (except for a fringe of hairs on the legs and carapace) and also common here. High time to have a look again underwater as well.
l have not made much progress sorting through recent seaweed pics but it is easy to post two recent photos that came out well. Above the Spiny starfish Marthasterias glacialis. This seastar can grow up to 70 cm across, but on the shore you generally do not find them much larger than 20 cm. It occurs from Northern Norway down to West Africa. Below a patch of Snakelocks anemones Anemonia viridis, probably originating via binary fission. The most common anemone in the rockpools here, around half are this tan colour, the other half is green with purple tips. No one knows why. (And interestingly, it is not the only anemone species that shows two colour variants, beadlets are red or green, plumose anemones white or orange). Although the water was 9C, with the sun on the white sand it looks pretty tropical to me, a clownfish would not have been out of place! (I took a photo of this same patch in March but that one was not nearly as good.)
Some photos from Last Sunday at Castle Beach in Falmouth. Above, the periwinkle Littorina littorea, which aggregrates in great numbers on the upper shore. Below, three echinoderm cousins: a Cushion star Asterina gibbosa and a little Sea cucumber Pawsonia saxicola with a Brittle star in the background. It was the first time I saw this beautiful colour variant of the Risso’s or Furrowed crab Risso pilipes. More common is the very similar Montagu’s crab Risso hydrophilus, there are usually 5-10 individuals under a single rock. The small ones especially come in a range of colours that make them excellently camouflaged against the pebbles. Next a juvenile Shanny Lipophrys pholis, a detail of a Corkwing wrasse (I could pick it up, that is how low the tide was) and a shot of the beach, showing the versatility of the mzuiko 60mm lens.
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.
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!
These photos are from a couple of weeks back; since the weather has been hideous most of the time I have not been out much since. More practice with the m.zuiko 60mm macro lens abovewater. Above a small Strawberry anemone. Below a small Cushion star Asterina gibbosa and my finger tip for size. Below that the hydroid Candelabrum cocksii and an Idotoea isopod species (there are several common Idotoea species but I have not paid much attention to them yet I must admit). Finally, the adorable Worm pipefish Nerophis lumbriciformis which is common and usually found in small groups under rocks (I have never seen them underwater as they are small, slow, well-camouflaged and probably hidden most of the time). Definitely will try to get some more portraits of these lovely fish!
It has been a long time coming, but I finally managed to go on a boatdive to the Manacles this weekend. I rented my gear at Seaways in Penryn and got on board the Atlantic Scuba rib ‘Stingray’ in Mylor Marina. Nine divers were on board; I was teaming up with Thomas and his intern Andy from HydroMotionMedia (make sure to check out the revamped website), who are working on a documentary about Marine Conservation Zones (the Manacles are one). The Manacles are a group of rocks east of the Lizard peninsula about half an hour by boat from Mylor which historically have claimed many ship wrecks, and they form one of the best dive sites in the UK. The name is an anglicization from the Cornish ‘Meyn Eglos’, meaning church stones. It was a beautiful sunny morning, and when we were close we spotted several Common dolphins Delphinus delphis, who came up to the boat, an awesome start! At slack tide, we descended to about 18 meters to inspect the walls of Raglans reef, the outermost pinnacle of the Manacles group. For the first time, I saw many of the species I was familiar with only from the internet and books with my own eyes: Cuckoo wrasse, Dead men’s fingers (a soft coral), Ross coral (which is not a coral but a Bryozoan), enormous amounts of Feather stars (see this recent post when I found them first on holiday in France), Sun stars and of course the incredibly pretty Jewel anemones Corynactis viridis:The photos are OK but I could do a lot better, this was in part due to my camera malfunctioning for a bit and my dive was pretty short anyway, as I guzzled too much air (I need to do some sports and drink less beer!). Also, I need a lot more practice with video light and strobe. However, this dive was primarily about checking out the new scenery. Some shots of other species below: the Edible sea urchin Echinus esculentus, Elegant anemone Sagartia elegans (variety rosea) and Dead men’s fingers Alcyonium digitatum. I hope to go back to the Manacles on the Stingray very soon!
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…
I started this blog mainly to document keeping a temperate marine aquarium; browsing back I see that that was more than four years back already! (see this introduction). Over time, I became more passionate about rock pooling, snorkeling and diving, specifically about seaweeds and photography, and blogged less and less about my aquarium. The aquarium had its ups and downs, as coldwater aquariums tend to be a bit more trial and error (coldwater marine aquariums do not consist of relatively slow growing stony corals as in tropical marine aquariums and house much more (higher order) diversity than tropical or cold freshwater aquariums). Also, I am a lazy man. The last aquarium update was from last November and the aquarium did not look that great, but I have lately spend more time on it and it looks much better now, so here a quick new post.I bought an upgrade Red Sea Max pump (much better) a while back, and more recently a Tunze 9001 skimmer (MUCH better than the stock skimmer, removed years ago as it was so noisy). The only problem is that the pump is so powerful that the water does not get sucked fast enough in the back compartment and it starts to run dry, I need to think how to fix that. The water is very clear though. I only have Cornish suckers as fish at the moment, and it might not be safe to add other fish as there are quite a few anemones at the moment. I have collected a bunch of Daisy anemones Cereus pedunculatus whilst diving (these are very common here in Flushing). I feed all my anemones small pieces of defrosted prawn by hand, these little ones respond very well to that and I hope they will grow much larger. I also collected some more Redspeckled anemones Anthopleura balli (below). David Fenwick kindly gave me an oyster with many Jewel anemones Corynactis viridis attached (crappy pic, sorry). These did relatively well for a while when feeding fine dry foods (sold for reef aquariums) but they were bothered by the squat lobster and cushion stars and I put the oyster back in the sea (I was also worried the oyster might die and cause a huge nitrogen spike). As an experiment I removed a few jewel anemones with a scalpel and superglued them to frag plugs but they did not survive. Ah well, that might have been a first, so worth a try. With a smaller, dedicated aquarium with better filtration (to deal with many small food particles) it must be doable to keep these. At the moment there are several species of gastropods, a cute little clam, mussels, Snakelocks- Dahlia-, Beadlet- and Strawberry anemones, a small Hairy crab, Cushion stars, green urchins and a Common starfish. The echinoderms seem easiest to keep of all. I actually put the common starfish back as it was picking of all my snails which I need to keep algae in check (and are interesting in their own right of course). I added a Cushion starfish with six legs though (‘Dave’). Hopefully I can find some more anemones when diving over the summer and who knows experiment with seaweeds again.