Wednesday had a good low tide, sun and no wind so I headed out for the water during my (long) lunch break. I was not disappointed with the viz, although the wireweed and thong weed shed tissue (conceptacles and/or epiphytic algae?) which immediately cloud the water so you have to ‘swim and shoot’ before the opportunity is gone. At this time of the year, the seaweed biomass is at its greatest, with lots of Harpoonweed, Wireweed, Sea lettuce, Bushy rainbow wrack and Thong weed but the biodiversity is lower, with many other species such as Discoid forkweed, False eyelash weed, Bonnemaisons Hookweed and Red grape weed gone or decaying. Below some general impressions (more photos from around the same time last year here and here): On the two photos above Bushy berry wreck Cystoseira baccata (along with Brown fan weed and Oyster thief). There are many big snakelocks anemones around and quite some fish, mainly shoals of juvenile pollack, Corkwing wrasse and Ballan wrasse, Two-spot gobies and, beyond the pools above the kelp forest, shoals of sand eels and sand smelt. The wind has picked up again so no more snorkelling in the coming days. I’d love to go for a dive again but my strobe malfunctioned and is back with the manufacturer for repair and so I might wait a bit going back into the water….
Above the spot where I have been snorkeling all year at Tunnel Beach, between Castle- and Gylly Beach, in Falmouth (Pendennis Castle can be seen in the background). The best time to snorkel is before low tide, as when the tide comes in the viz gets worse. I try to aim for 50-100 cm above the low tide mark which is really shallow. This area is not a real rock pool but rather a gravelly zone between the rock pools proper and the kelp forest which begins past the last row of rocks on the photo. Last week I went snorkelling three times but only last Thursday had decent viz. The photos below show the abundance of pink Harpoon weed Asparagopsis armata, green Sea lettuce Ulva lactuca and new growth of Thong weed Himanthalia elongata and older plants covered in red fuzzy epiphytes. The old wireweed Sargassum muticum plants have died off and the remnants are covered in many epiphytes such as Juicy whorl weed Chylocladia verticilata, Cock’s comb Plocamium cartilagineum and the pretty Iridescent fern weed Osmundea truncata. However, there is new growth everywhere as well so, like Himanthalia, this species seems to have a half-yearly lifecycle. Below some Irish moss Chondrus crispus next to Wireweed. After that, lots of little fuzzy Falkenbergia growing on top of Discoid forkweed Polyides rotundus. This combination grows in a large patch and looks interesting but I struggled to get decent photos, as the dark seaweeds on very white gravel mess up the white balance big time. Next one or two different species of fine flat reds, the last probably Nitophyllum punctatum. The Bushy rainbow wrack Cystoseira tamariscifolia is dying off (here overgrown with Asparagopsis and Dictyota) but the related Bushy berry wrack C. baccata is doing well. Among its epiphytes Spiny straggle weed Gelidium spinosum (ID thanks to Seaweeds of the Atlantic facebook page members) which is also freeliving, and finally the green Codium fragile. One time, when the tide came in, the water was super oxygenated, and all surfaces were covered with small silver bubbles which was beautiful (and annoying as the camera lens was also covered). The following photos show a very different looking Codium fragile, C. tamariscifolia overgrown with Sea beach Delesseria sanguinea and more Thong weed.
We went to check out Prussia Cove (named after ‘the king of Prussia’ John Carter who used it as his smuggling base in the 18th century) this weekend for some snorkeling action:
The weather was great but there was quite a lot of wind and so the water was choppy and the visibility really bad. We saw hardly any fish. The seaweeds consisted mainly of the common Thong weed Himanthalia elongata and Bushy berry wrack Cystoseira baccata. There were not many rock pools. The only interesting find there was the pretty Brown tuning fork weed Bifurcaria bifurcata:
The weather was terrible last weekend so I only went for a brief trip to Flushing beach. It was noticeable that the Dumont’s tubular weed Dumontia contorta, abundant during the last months, is disappearing and flat red and green seaweeds are on the increase:
I found some Bushy Berry Wrack Cystoseira baccata (I think) and a very fine red seaweed that I could not identify using my Seasearch Guide to Seaweeds of Britain and Ireland:
An Estuary ragworm Hediste diversicolor:
My main aim was to get some finer sand to replace the coarse, white gravel collected from Maenporth beach that I have in my aquarium now. This sand is formed for a large part by remnants of Maerl, species of coralline algae. Beds of Maerl nodules are a threatened and important habitat for many animals and also other seaweeds.
With the seaweeds collected, it was time to plant my aquarium. This time I took a more serious approach, I planted lots. Many of the seaweeds had bits of rock attached to their holdfasts which made it easy to anchor them in the gravel. Two of the weeds I tied to rocks with a piece of elastic band, easy peasy:
View from the left side. False eyelash weed Calliblepharis jubata in the front, tall Wireweed Sargassum muticum and in the middle some coarse brown sea weed which almost looks like a dead conifer. This is probably Bushy berry wrack Cystoseira baccata:
An expanded view, on the right some Red grape weed Gastroclonium ovatum, in the middle the red pluck of Dudresnays whorled weed Dudresnaya vertillicata that I already had:
A goby amidst the False eyelash weed lying on top of what may be Purple claw weed, I am not sure:
The magnificently coloured Bushy rainbow wrack Cystoseira tamariscifolia covered in green Snakelocks anemones Anemonia viridis. In the foreground the pink Slender-beaded coral weed Jania rubens and Harpoon weed Asparagopsis armata.
A close-up of the Bushy rainbow wrack. Other plants were bright green or purple. I never knew that seaweeds existed with these iridescent colours. In fact, when I glimpsed one for the first time in a rock pool I disregarded it because I thought it was some seaweed covered in oil slick! These weeds are also have a very cartilaginous texture which give them more of an animal-like appearance.
I discovered several small whitish Sea lemon nudibranchs Archidoris pseudoargus, very cool.