This is a weird little hydroid and so only has a Latin name to go by: Candelabrum cocksii. It was first described by Cocks in his ‘Contributions to the fauna of Falmouth’ in the 1850s and it is quite common locally. I find them mostly as pictured here, but sometimes I see them with their foot extended, going from a centimetre to 8 centimetres or so in length. This allows them to rove over the rock surface in search of tiny (crustacean) prey. Their mouth is located at the end of the trunk which is covered in ‘capitate’ tentacles (see the pic below for anatomical labels). The white spheres are gonophores used for reproduction. It should be possible in summer when these hermaphrodites reproduce to see dedicated clasper tentacles holding the embryos, that would be cool (to me at least!). Btw, I remembered I posted about this species not even that long ago! See here and also see this link and this link from fellow enthusiasts across the pond who likewise have been fascinated by Candelabrum.
This seems like a familiar way to start a blog post but here I go again: ‘the weather has been terrible lately and I have not been in the water!’. March used to be my favourite time for snorkeling because the seaweeds look at their best, but the last three years it has been windy and wet, surely because of climate change…
To keep the blog going (a bit), I have dug out some images from a few dives last year featuring Inachus spider crabs. There are three species, I. phalangium, I. dorsettensis and I. leptochirus, which can be told apart by the arrangement of tubercules on their carapace, but these are often obscured by epiphyte growth, and so I am keeping it to Inachus sp. All species are associated with Snakelocks Anemone (Anemonia viridis) hosts. The photo above is taken using a weird ‘wide angle macro’ wetlens (INON UFL-M150 ZM80). This perspective always fascinated me but it is difficult to achieve. This lens does the job, although it is incredibly ‘soft’, especially around the edges. The close focusing also makes it difficult to direct the strobe light on the subject. So there is a tradeoff between getting the surroundings in view and sharpness. Below first some sharper shots using my 60mm macrolens, followed by some macro wide angle shots (they happen to be each of the different Anemonia colour morph):
I will leave you with the following interesting bit on the biology of these crabs by Diesel (Ethology, 1986):
I. phalangium females are site-constant, and live in the protection of one anemone or group. Males travel frequently between anemones harbouring females due to spawn; they copulate and guard the females until spawning, after which the male leaves again. A male operates in a patrol area containing 3-8 anemone groups and up to 8 females, visiting each female in turn repeatedly just before it is due to spawn. Patrol areas of different males may overlap, with resulting competition to fertilize a female’s next brood. Large males have higher reproductive success than small ones. Females live up to 8 months after the moult of puberty and hatch up to six broods, and males live up to 7 months as adults. A male could fertilize a calculated 26,000 eggs, whilst a female’s reproductive potential is ca. 4,200 eggs. Mortality risks are higher for males than for females, probably because of increased predation while leaving the protection of anemones in order to visit females. Males learn the positions of anemones harbouring females in their patrol areas, and when these are due to spawn. This allows a male to travel with a target and arrive punctually to fertilize the next brood due in his circuit. I. phalangium is the first marine invertebrate reported to use a “schedule” of localities and times for visiting prespawning females. In this way males minimize searching time and mortality risk, and maximize the number of broods fertilized.
When the viz is bad, I take my macrolens (sometimes with the Nauticam CMC-1 wetlens for a bit of extra magnification) out to the pools. Sometimes I stick to the surface of rocks and seaweeds (to look for stalked jellyfish for instance), but other times I turn over rocks under water to see what hides beneath. Quite a lot! There are larger animals, such as Topknots and different types of crabs (and Worm pipefish as pictured here) but mainly they are quite small (around a centimetre or even less). See the selection below (Tricolia, Bittium and Limacia were not from under rocks but I had to make the grid fit!).
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!
The sun is shining (most days) and the water has warmed up, so ideal conditions for a bit of snorkeling. I have been out at my usual spot in Falmouth (rockpools and kelp forest) and my local beach in Flushing (seagrass) (and yes, I really count myself lucky every time that l live here!). The last couple of times I have brought my son along, as he is now old enough (nine). He is a nature freak just like his dad, actually probably more so! I need to get him fins and a weight belt soon, but he has been doing fine in the water already.
The photos above and below illustrate the state of the rock pools at the moment: quite brownish with the Sargassum and Himanthalia growing everywhere. The red, pink and purple species have largely disappeared (apart from Harpoon weed) and there is quite a bit of green Ulva growing. The water teems with juvenile pollack in the rock pools and schools of sand eels a bit further out. Diving over sandy patches, you can see the latter species shooting out of the sand en masse. It is crazy how such a silvery pelagic fish can also burrow in the sand. I guess it does take its toll, as there are quite some dead ones to be seen too.
The Flushing snorkel site is very different, no (deep) rockpools, only a little bit of kelp but with a very healthy patch of seagrass. No catsharks or thornback rays when we went in, just the odd small sea bass. There are many small Snakelocks anemones on the seagrass. I used to think that it was mostly the purple form that did this but I now noticed that most were the green variety, so the morphs do not seem to differ in this respect after all. One anemone had ‘caught’ a crystal jellyfish (an Aequorea medusa). Not sure if it was in the process of being digested or just ‘stuck’.
I have played around with my new INON strobe, which works a lot better than my old strobe. I have ordered a second one for Wide Angle photos too….(as you can see there is quite some backscatter in the pic of the Shore Crab above). I will need to get back to some shore diving to make optimal use of two strobes, as I am too lousy a freediver to get the lighting and exposure right in one breath!
The weather has been horrible lately, with three storms coming in straight after each other. On the upside this means that there is good potential for beachcombing, but alas, the one beach on the North Coast we checked was as clean as a whistle, just sand! So here are some photos from a few weeks back when the weather was good better. On top a Spotted Kaleidoscope Jellyfish (Haliclystus octoradiatus), about 15 mm across, on some Irish Moss seaweed. Please see this site for more information on these beauties; there are several species in our rockpools, but you have to develop a bit of an eye for them! Some other pics below: Blue-rayed Limpets (Patella pellucida) on kelp and a Thicklipped Dogwhelk (Tritia incrassata (when I was young Nassarius incrassatus…). Still need a lot of practice with the strobe, these shots I was very happy with, but most were way off the mark somehow. Looking forward to spring!
It is that time of the year again: gales, rain and darkness. The only good thing about late autumn/winter to me is that the wind blows interesting things on the beach. Portuguese Men o’ War (Physalia physalis) have been a common sight the last few years (see this post from 2017), perhaps more so than it used to be, but not sure this has been properly investigated. Yesterday we saw several dozen at Loe Bar near Helston, including the smallest specimen I have seen so far. No By-the-Wind-Sailors Vellella and no Violet Snails Janthina, and definitely no Porpita or Glaucus; maybe someday!
The jellyfish are upon us again. Slow and photogenic, I had to go out yesterday in Falmouth Bay to try out two strobes with my fisheye lens for the first time. Unfortunately, the sea is like pea soup at the moment. The wide angle allows for a close focus (getting right up to the subject) so that minimises the problem of low viz, but there still is a problem with backscatter (especially when the strobes are not positioned the right way). Anyway, I had a lot of fun practicing. Although they did not come out as crisp as I hoped, cropping, decreasing highlights and increasing contrast and clarity, made them look acceptable. I encountered a few Compass Jellyfish Chrysaora hysoscella, one with a small Gadoid fish in tow (above). A bit more common were the Crystal Jellies (in the Class Hydrozoa and so not ‘proper’ jellyfish as in the Class Scyphozoa) pictured below. They are in the Aequorea genus but I am not sure of the exact species. The Barrel- and Blue Jellyfish will soon follow, giving more opportunity to practice wide angle strobe photography.
Two days after the last post I went back to my usual spot, fisheyelens on the camera. After a little recce it was obvious that the water was too milky, so I went back to the car and changed to the macrolens. It was overcast and the water was chilly. I’d seen some stalked jellyfish (see this great resource stauromedusae UK) the last time. Of course, when you are specifically looking for something you don’t find it, but in the end I noticed a Spotted kaleidoscope jellyfish Haliclystus octoradiatus, the most common species around here. I still struggle with my strobe, so all photos were riddled with backscatter. I could remove most of that in Photoshop luckily, but it is frustrating, especially as I had a run diving last year when I had no such issues at all. I encountered a 15 cm or so Longspined scorpion fish Taurulus bubalis as well. I cropped the shot and could put some colour back in using Windows Photos. Hope to go back over the weekend.
I joined a seaweed identification get-together at the Cornwall Wildlife Trust organised by Matt Slater last week. It was fun to chat with likeminded people and also made me want to stick my head underwater again! The weather has been horrible for over half a year now and I have been in only a few times, with little chance to take decent photos, hence the blog inactivity. This has been especially frustrating as March is the best month for seaweeds (see the 2017 Falmouth Seaweeds tag) and I am missing my window. I therefore jumped in the next day. The tides were at their very lowest, actually too low for most of my usual rockpool spot! The viz was not great due to the 20+ mph winds but just about good enough for the fisheye lens. I really hope for some good weather in the next 2-3 weeks to be able to make the seaweed photos I really have in mind.The very top photo is Berry wart cress Sphaerococcus coronopifolius shot with a very shallow depth of field. The single stone above hosts a whole variety of species. The largest is Slender wart weed Graciliaria gracilis and just as the Berry wart cress it is covered in mucus threads, which must come from the tiny gastropods Rissoa parva that can be seen on it when you zoom in. To the left the wiry Black scour weed Ahnfeltia plicata. To the back the invasive Devils tongue weed Grateloupia turuturu. Green Ulva and young kelp can also be seen. Below some Harpoonweed Asparagopsis armata. The snakelocks anemones Anemonia viridis were also out in force. I hope the weather settles soon!
An Bollenessor 