Falmouth Seaweeds: End of April

A quick snorkel this Tuesday to check out my favourite rock pools at Castle Beach here in Falmouth. The tide was low, the water still and the sun was shining, creating beautiful shimmers of light. The Wireweed, Thong weed, Sea lettuce and also the Bushy rainbow wrack are in full swing, but most of the other species are in decline, with for instance the Harpoon weed and False Eyelash weed bleaching. Still, it is very pretty! The most common fish encountered so far this year have been Two-spot Gobies, with the occasional wrasse or dragonet. Now, loads of juvenile Pollack Pollachius pollachius have appeared (ID thanks to the excellent folk at the Seasearch Cornwall facebook page). The following photos are all variations on the same theme; I could not decide which ones were best so I just posted the whole lot: In the photo above you can make out some Snakelocks anemones on the right; compare with the last two photos of this post from six weeks ago to see how the same scene has changed. The stalked jellyfish seem to have largely disappeared along with the decline of seaweeds. However, you can still spot the odd interesting animal. The photo below is of the small gastropod Mangelia costata Haedropleura septangularis. Probably not very rare, but small (<15 mm) and well-hidden and so not that often seen:

Aquarium Update 16

It has been more than five months since the last update on my Red Sea Max 130D so high time for nr 16. I have bought a media basket to force the water more through the filtration material, which cannot be a bad thing, but otherwise have done very little. I have not been diving as much as I wanted, and still have not gone to any of the deeper sites where I perhaps could have found some Dahlia anemones, larger Brittlestars or other interesting things. I have a red seaweed growing from the rocks; it has encrusted all rocks in a deep red colour and grows out of in a bit of a lettuce-shape. At first I thought it was the invasive species Grateloupia but the shape and colour are a bit different, I will enquire at the Seaweeds of the NE Atlantic facebook group what it is. I have some green algae but they grow in tufts that can be easily removed so I cannot complain really. Below a shot of the tank, it does not look great but there you have it:img_7419The anemones are still so-so. I think that plumose anemones need very fines foods and water changes, which I do not really do and as a result they are often closed and not growing. The strawberries and beadlets still don’t do as well as they did, no idea why. My Red-speckled anemones (Anthopleura ballii) on the other hand do great and are my favourites. Below a photo of a specimen I collected at a good low tide in Flushing this week and one in my aquarium that has grown quite a bit. It fluoresces in the middle. img_5611img_7401I have some squat lobsters rummaging around as well as a cool hairy crab. I have got rid of prawns as they are so aggressive! Every time I opened the hood and stopped the pump, they came swimming to the top, legs tickling and scraping on the plastic and attacking my fingers. They are part of the reason that my fish have not fared too well. I had some Pollack for a while but they eventually succumbed. I believe my flow is on the strong side, and with an occasional missed feeding and less energy, the prawns and anemones will not tolerate any slip up! I caught some Sand smelt (see here for two videos) with my big net from the quay but these formed a meal for other inhabitants within the day. I caught a Topknot (by hand) (see here) but that disappeared after a while too. I have two or three Cornish suckers that do well though. As soon as I feed they stick their noses from under rocks and dart out to catch some defrosted shrimp but otherwise you hardly see them. I was lucky to catch a bright green juvenile Ballan wrasse Labrus bergylta of the quay which does great (they are not as nervous as the more common corkwing wrasse). I caught another individual (I only ever caught three) but the first one started picking on it, changing from bright green to a more subdued marbled green. I was not in time to release one of them and the second fish died unfortunately.

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aquarium update 11

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!IMG_7849 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).IMG_7908IMG_7652One 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.IMG_7651IMG_7914Now 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. IMG_7887

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first dive in Cornwall

A couple of weeks ago I went for a bit of a spur of the moment after-work dive with colleague Andrew (like me a quite unexperienced diver) and his friend Charlotte Sams. Charlie is an experienced diver and natural history photographer, who has her own blog: Charlottesamsphotography, which you should check out. We dove in Falmouth off Pendennis point. The water was not very clear (maybe 5-6 meters visibility) but the temperature was quite nice. We saw (amongst others) Sand eels (do not know which of the two species), Pollack Pollachius pollachius, Dragonets Callionymus lyra, Two-spotted gobies Gobiusculus flavescens, a Tompot blenny Parablennius pararugine, very large Ballan wrasse Labrus bergylta and a beautiful little John dory Zeus faber:

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We also saw some very large Common starfish Asteria rubens and also a nice Spiny starfish Marthasteria glacialis. We dove only to about 5-7 meters, which meant we could stay in quite long, over an hour. At seven meters, the bottom was a sandy expanse, interspersed with mounts of Laminaria Kelp covered in hydroids. In-between the kelp were other seaweeds, such as Red rags Dilsea carnosa but I was more focused on the animals during the dive. In shallower water were enormous bundles of Wireweed Sargassum muticum (also known as japweed but that is not very pc…) and the very long slimy Mermaid’s tresses or Bootlace weed Chorda filum. Snakelocks anemones were very common, and we managed to also see Leach’s spider crab Inachus phalangium, which lives associated with these anemones. All in all a fantastic experience, and I hope to find the time to go diving very soon again!