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!
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:
I usually head down straight to the lowest reaches of the shore when rock pooling, but when there is a neap tide and a lot of inshore wind as there was this weekend, you have to make do with turning rocks higher up the shore. Although biodiversity is lower, there are some species that are only found there (see for instance this recent post) and so it is actually nice to have a look there for a change. The very first rock turned over actually had a couple of interesting inhabitants underneath it. Another lifer, the tiny gastropod mollusc Onoba semicostata (surrounded by a couple of even tinier Rissoa parva), very quickly identified by members from the British Marine Mollusca facebook group:
The same rock had a number of the tiny (< 1 cm) Cushion star species Asterina phylactica on it as well. It is prettier than the common Cushion star Asterina gibbosa (one of my favourite aquarium species), but perhaps a bit too small to be an option for the tank.
One other beautiful species, the colonial tunicate Botryllus schlosseri, this is a nice blue/purple one: