I have been diving three times last week but due to internet problems have not posted about them. I hope to do that in the coming days, but first wanted to blog about this mornings snorkel session in the shallow rock pools at Castle Beach in Falmouth, as I experienced the best viz (visibility) ever here. Apart from the stunning viz, I was very lucky with the fish: I spotted a Tompot blenny, Two-spot Gobies, Fifteen-spined stickleback, Rock goby, Pollack, Ballan-, Corkwing- and Goldsinny Wrasse and Sand eels (above and below). However, I mainly wanted to check what the seaweeds looked like, and things have definitely changed over the last month (see here).The Wireweed Sargassum muticum and Spaghetti (or Thong) weed Himanthalia elongata are thriving and at low tide hang over the surface creating ‘tunnels’. The Harpoonweed below is in decline, turning from pink to yellow-white (and the Bonnemaisonia is almost completely gone). The fronds of the False eyelash weed have turned from juicy and red-brown to wiry and yellow and the corraline algae are turning white. The Sea lettuce Ulva has died back and is covered in speckles (sporangia?). Some epiphytes are thriving, the very fuzzy brown Pylaiella littoralis covers kelp, a Ceramium species grows as pompoms on the Spaghettiweed. One pink and fuzzy species that is growing well I should have taken a closer look at because I am not sure what it is now (I will enquire at the Seaweeds of the NE Atlantic facebook group). The next species I think I can identify: Chipolataweed Scytosiphon lomentaria. The Bushy rainbow wrack Cystoseira tamariscifolia looks fuzzier and greyer than before. Although with less species and more subdued colours, the pools still look beautiful, and I hope the good visibility will last a bit longer!
I have not posted too many pictures of seaweeds in rock pools because they are a real pain to properly photograph. However, when rock pooling two weeks ago in Falmouth, my friend Thor took some great pictures using his DSLR, two of which shown here. The IDs of these two epiphytic seaweeds on wracks were verified with invaluable help from Seaweeds of the NW Atlantic facebook group members: the first picture is Pylaiella littoralis (a species I had only seen on kelp sublittorally). The second species is Polysiphonia (or Vertebrata) lanosa:
This snorkel session was also the first time I took a proper look underneath the kelp. Mowing through this forest is very interesting. Besides the gobies and starfish, there are a lot of sponges, bryozoans and hydroids to be seen. A picture from this ‘turf’ with many hydrozoans and a larger erect bryozoan (perhaps an Alcyonidium species?); these are groups I know very little about. A photo beneath that of some worms Bispira volutacornis, very beautiful:
The kelp is covered by a not so pretty, large, fluffy brown seaweed which might be Pylaiella littoralis (first picture). Large bushes of the slightly iridescent Dictyota dichotoma were also common, this is a species I have never seen in rock pools (second picture). The rocks underneath the kelp are also home to many red seaweeds, notably Sea Oak (I have to get back for some pictures).
In the deeper channels there were many Mermaid’s tresses Chorda filum, more than five meters in length. The shallow rocks were covered with Thongweed Himanthalia elongata and Grape pip weed Mastocarpus stellatus with assorted epiphytic tufts of fine red seaweeds.