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!
It has been over 20 months since I last posted about my Cornish native aquarium, so high time for a quick update with a few iPhone pics. In short, everything has ticked along nicely and nothing major has happened. Grey Top shells keep the glass pretty free of algae, I do not think I have ever had to clean the tank myself this year. I tried to keep a small piece of Dead Mans’ Fingers but it unfortunately perished. I think this mainly had to do that I was not able to attached it to the rock (using elastic bands). If I could get my hands on a piece already attached to a rock I think it would work.
My main goals is to keep some new species of anemone, and I will try to find some soon when diving. Currently, I still have the Daisy-, Dahlia-, Beadlet-, Strawberry-, Red Speckled- (see pic above) and Snakelocks Anemones. The Beadlets are producing lots of babies, some of which already have grown up to half the size of adults. I have each of the two Snakelocks colour morphs and both anemones have divided in two and grown quite a bit (see pic below). There are at least ten other species I could collect, and it would be great to have a whole collection. Anemones are generally easy to keep and very pretty! I feed them a few times a week with frozen foods such as artemia and I also handfeed them with bits of defrosted shrimp.
My Cornish Suckers (a species of clingfish) are still in there, but I only see them when feeding. I am reluctant to add more fish, as the tank has become a bit of a death trap with all the anemones! I have a common starfish, a few cushion starfish, some netted dogwhelks and a sea urchin. I will add some small prawns again as well since they are quite beautful and always on the move (and if they end up as anemone food, well, that is fine too). Occasionally, I add a random find to the tank, see below a colonial seasquirt on a shell I found on the beach and a shell with some Seabeard hydroids (Nemertesia antennina) attached that I picked up during a dive.
Hardware-wise, I am very happy with the Red Sea Reefer 170 and my AI Prime LED light. The LEDs are operating at very low capacity though, I use less than 10% of the output I think. I use a skimmer, but do not have biological filtration in the sump and rely solely on the gravel in the tank. I have a separate chiller loop going in and out of the sump. The tank currently is kept at 16C, which is not supercold for a coldwater tank, but it avoids problems with condensation (and saves some energy). My water changes involve a walk to the quay at the end of my street with two 10L jerry cans. I try to do a water change once a week but I do not always succeed. So hopefully I will be able to add some interesting species to the tank soon. Finally, watch this space for some very interesting coldwater aquarium news early next year…..
P.S. click on the ‘Aquarium Update’ tag on top to see all old posts on my aquarium
Two weeks ago we werelucky to spend a mid-week on St. Martins, one of the Scilly Islands. The Scillies are a group of tiny inhabited and uninhabited islands 28 miles off Lands’ End (before I moved to Cornwall eight years ago, I had never even heard of them…). The water over there is bluer, the sand is whiter and the viz much (much) better than in ‘mainland’ Cornwall, so a true paradise for snorkelling. I tried to get underwater as much as I could, in-between exploring the island (and going to the one pub). As we did not have much time, I mainly snorkelled in the seagrass just off Par Beach. It does not really look like England does it!? The seagrass was teeming with stalked jellyfish. However, because of the great viz I stuck with my fisheye lens, which meant it was tricky to photograph them. This species is Calvadosia campanulata, a protected and generally uncommon species, so worth recording (which I will get on when work is quieter and the weather is crappier). The ID was confirmed by expert David Fenwick, have a look at his excellent site on stalker jellies stauromedusae.co.uk (and his general site for marine species in the SW of the UK aphotomarine.com). Dave also pointed out some other organisms growing on the seagrass seen on these pics: the small red algae Rhodophysema georgei and the slime mold Labyrinthula zosterae (the black bits). As always, I learned something new talking to Dave. Snakelocks anemones were abundant on the seagrass, and the sand inbetween was full of Daisy anemones and Red-Speckled anemones Anthopleura balli (one of my favourites, they do well in my aquarium). As always, I bother crabs by sticking a lens in their face. Bigger Green Shore Crabs Carcinus maenas can get a bit feisty and attack the dome port (maybe because they see their own reflection). Finally a juvenile Straight-nosed Pipefish Nerophis ophidion (about 3 inches), a new one for me. I am always facinated by piepfish (and hope to one day see a seahorse). Unfortunately the shot is not in focus, I really needed a macrolens for this one. Still, you can marvel at the white sand and blue water! Some photos are allright, but I could do a lot better with a bit more time. Luckily we rebooked for a stay in spring already!
I started a Cornish shell collection with my children recently. So yesterday we went to our local beach on Flushing to look for new additions. Lying down I took a really close look and was rewarded with a whole bunch of tiny species. On this photo, 14 species comfortably fit on a square inch. Species names in a clockwise spiral:
Tritia incrassata (Thick-lipped Dog Whelk)
Trivia arctica (Arctic Cowrie)
Tricolia pullus (Pheasant Shell)
Bittium reticulatum (Needle Whelk)
Littorina obtusata (Flat Periwinkle)
Calliostoma zizyphinum (Painted Top Shell)
Steromphola cineraria (Grey Top Shell)
Littorina saxatilis (Rough Periwinkle)
Tectura virginea (White Tortoise Shell Limpet)
Peringia ulvae (Mudsnail)
Nucella lapillus (Dog Whelk)
Steromphola umbilicalis (Flat Top Shell)
After posting this photo on the Seaweeds of the NE Atlantic group, I received a lot of positive replies, and Jason Spencer-Hall, Professor at Plymouth Uni and president of the British Phycological Society asked me to submit this photo for the annual Hilda Canter-Lund Photo competition. This award was established in recognition of Hilda Canter-Lund, whose photomicrographs of freshwater algae combined high technical and aesthetic qualities whilst still capturing the quintessence of the organisms she was studying. I am pleased to say I ended up as joint winner (there is always a micro-algae and a macro-algae winner), prize money included! The caption:
Carpodesmia tamariscifolia (Bushy Rainbow Wrack) framed by Himanthalia elongata (Thong Weed) in a rockpool in Falmouth, Cornwall, U.K.
I took this photo of this stunningly beautiful iridescent Rainbow Wrack spring 2020 at a low tide when this rockpool was no more than a meter deep. This species is a perennial that forms a home to many animals, from sponges to tunicates, and is often used by the Bull Huss to attach its egg cases to. Many seaweed species also grow epiphytically on Bushy Rainbow Wrack, such as the invasive red species Bonnemaisonia hamifera on this photo. Photo taken using an Olympus OM-D E-M5 Mark II with an 8mm fisheye lens and with a single automatic strobe.
Definitely THE photo competition for me and I hope to get more good shots for the 2021 installment (most probably next March/April). As this post is short, below a photo (taken with my old camera) I submitted in 2017 (I managed to forget about the competition in the intervening years).
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.
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.
A day without wind last Thursday and so time for a look at the seaweeds. As expected, the pinks, reds and purples have made way for browns, yellows and greens. The water was a bit cloudy but with the wide angle lens you can get close up minimising the effetc of the bad viz. Wrasse were tending to nests and tiny pollock swam around but otherwise I could not spot not many animals; the exception was a big spider crab who was as startled as me. Above the common species Thin Sausage Weed Asperococcus fistulosus. Not the most beautiful species but let’s say it looks interesting. To my horror, I discovered that my favourite seaweed Bushy Rainbow Wrack has changed genus and is now called Carpodesmia tamariscifolia instead of Cystoseira tamariscifolia. I hate name changes in general but this just an ugly name! Two photos of this species below as well as one of Bushy Berry Wrack Cystoseira baccata which also has moved genus and is now Treptacantha baccata… After that a floating piece of Desmarest’s Flattened Weed Desmarestia ligulata and some Pale Patch Laver Pyropia leucostica.
A while back I thought it might be an idea to experiment with flash photography. Using one flashgun (strobe) I set out in my usual spot. I should have tried this a lot earlier! Although supershallow water has enough light to do without flash, a main problem (for me at least) is to balance harsh white sunlight (from above and from reflections from the white sand below) with the darker subject. By illuminating the subject, this effect evens out. I took probably almost a hundred photos of the Bushy Rainbow Wrack above and this one came out alright! Apart from the Thong Weed framing it, I like the row of Thong Weed ‘buttons’ in the foreground. I held the strobe in my hand for this one, and I used my older strobe, as my newerand more expensive manual one just not fires reliably for some reason (still trying to find out what is going wrong). Below some more strobe experiments. I really hope diving will be allowed soon so I can play around more with the wide angle lens and two strobes.