Some more seaweeds

Last Friday I went for another very shallow dip at Castle Beach in Falmouth. Even though the weather was pretty abysmal, it was definitely worth it! Here a small selection of photos, again the quality is not top notch but many pretty species to see. The first pic below shows the Hairy sandweed Cladostephus spongiosus remnants the Slender-beaded coral weed Jania rubens featured in the last post tend to attach to. After that, some Chylocladia verticillata, Dumontia contorta with Grateloupia turutura (past its prime) in the background, Heterosiphonia plumosa under a small overhang, a thin red (Rhodophyllis irvineorum? awaiting comments on the Seaweeds of the NE Atlantic facebook group) and finally Chondrus crispus and Dictyota dichotoma.

first snorkel with the Olympus

Yesterday I finally took my new camera underwater! I should have gone a bit sooner, but too be fair the water has not been looking very clear (and the viz was still not ideal). The sun was shining and it was great to be back in the water (perhaps 12C, not too cold with a wetsuit). It should be a great experience to shoot with a new, better camera, but it ended up being a bit of a frustrating experience not finding the right settings (I know, first-world problems!). I was stuck in Aperture Priority mode, which was a problem with significant wave action and the need for a fast shutterspeed. Although I took close to 200 photo’s, only a handful were halfway decent. Still, I learned a lot for next time. I took the 8mm fish-eye lens which allows you to get very close to the subject (especially useful for water that is not crystal clear) and still get a wide angle view. Above, a photo of an estuary sponge and seaweeds as well as Snell’s window. Below a badly composed shot of seaweeds, a downward shot of Furcellaria lumbricalis seaweed and Bushy rainbow wrack with Spaghetti weed in the background. All not very sharp and with flat colours, and hopefully standing in stark contrast to the next batch of photo’s!

back in the water

It had been over two months since I last went snorkeling at my spot in Castle Beach. Although I did go on two boatdives (with no photos to show for), let’s say the work-life balance was tipped in the wrong direction. However I had time for a low-tide snorkel this Saturday and it was great to be back in the water, with a Curlew as my only companion. It was the plan to practise strobe photography but unfortunately I did not manage to get my settings right and I was going nowhere. As this is an activity that is supposed to be fun, I decided to ditch the strobe and stick with natural light. Fish I spotted were Ballan- and Corkwing wrasse, two-spot gobies, tompot blennies, a fifteenspined stickleback, a dragonet and sand eels: It is pretty much the worst time in the year for seaweeds but the pools are still quite pretty. The first three photos give a general impression of the seaweeds, including Thong weed, Harpoon weed and Irish moss. After that: Codium spp,  Juicy whorl weed Chylocladia verticillata, a big plant of healthy-looking Hairy sand weed Cladostephus spongiosus, withered Red rags Dilsea carnosa and Dulse Palmaria palmata growing on a kelp stipe. I called it quits after two hours. On my way back I noticed an abundant green algae species I had not seen before. David Fenwick identified it as actually being a cyanobacterium rather than a seaweed: Rivularia bullata, interesting! Hope to do a lot more snorkeling before it gets too cold…

Gilthead Seabream

Yesterday I went for a late morning snorkel; although the water looked inviting, the viz was disappointing. I did not see anything of interest until I noticed a Seabream (15-20 cm) hanging about, not a species I had seen before! It goes to show that there is no dive or snorkel session whithout something that makes it worthwhile. The fish was not very shy, but I did not have weight or fins so I could not get down to get a proper shot from the side. I found out that this was a Gilthead Seabream (Sparus aurata). This southern species seems to have become more frequent on the South coast of the UK the last few years, probably due to warming seas. It seems to be known among anglers, but less so among underwater observers (the NBN Atlas only has two records for this species in Cornwall). Other than that the usual Ballan- and Corkwing wrasse, Two-spot gobies, Pollack and even a Blenny (very commonly found under rocks while rockpooling but I hardly ever see them when snorkeling).

Good Viz

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….

Falmouth Seaweeds October

To my regret I did not manage to take a look at the seaweeds at Castle Beach in September (it was my aim to go in at least once every month). Last Friday however, the sun was shining, the wind was gone and the tide was low (and I was able to escape work) so I at least could make October. Not only was the viz excellent, to my surprise, the seaweeds looked very healthy. It seems that there is a second, autumn seaweed bloom that I was not aware of. Some of the bleached corraline algae have regained their pink colour, the Harpoon weed Asparagopsis armata increased in abundance and I saw species such as Red grape weed Gastroclonium ovatum growing again. The Bushy rainbow wrack has partly died back, forming dense, dark-brown mats (fourth photo) but also show fresh growth. This species is covered in many epiphytes such as Brown fan weed Dictyota dichotoma, and remnants of Bull huss mermaid’s purses still cling on. Interestingly, Wireweed Sargassum muticum has almost completely disappeared. It is tricky photographing rock pool seaweeds. One main issue is to not disturb any sediment, especially as I keep it *very* shallow, sometimes lying on my stomach (I definitely do not need fins). The other main issue with using a (wide angle) wetlens is that there are three glass surfaces in front of the lens collecting bubbles and so need regular wiping. Light is also a challenge: photographing against the sun causes glare, but having the sun in your back results in casting shadows over your subject. I continuously fiddle with the exposure correction, but it remains difficult with the white sand and pebbles around the seaweeds. Below, some healthy looking Solier’s string weed Soliera chordalis, two photos of an ‘unknown’, Norwegian fan weed Gymnogrongus crenulatus, Under-tongue weed Hypoglossum hypoglossoides, seaweeds starting to grow on a pebble, and a rock covered in a variety of seaweeds.

Falmouth Seaweeds July

Last week I went for a little swim at the usual spot at Castle Beach. The viz was nowhere near as good as last month, but still OK. There are schools of sand eels and sand smelt and I even saw an eel. The contrast between growing brown seaweeds and withering red seaweeds has become even greater. Below you see some yellowed Harpoonweed and a ‘forest’ of Thong weed covered in epiphytes. As the light was a bit subdued, I focused on the most shallow area. The bare parts of the rock are covered with barnacles, dog whelks, sting winkles and limpets. The seaweeds are mainly Serrated wrack Fucus serratus, Sea lettuce Ulva, Grape pip weed Mastocarpus stellatus, some Ceramium and Laver Palmaria palmata, as well as Dumont’s tubular weed Dumontia contorta.

Falmouth Seaweeds (and fish) June

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!

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:

Falmouth Seaweeds: Mid-April part II

Above an illustration of the decline of seaweeds: Juicy whorl weed Chylocladia verticillata all white and fuzzy (see for a more healthy looking plant this post from 2.5 months ago) on a bed of the common and pretty Discoid fork weed Polyides rotundus. There seem to be around 25 or so  (larger) species that are common in these pools. Many of them can be seen in the two photos below (including a stray Bladder wrack, a species that dominates the shore just a meter higher): Below, a whole bunch of individual species. First, Sea beech Delesseria sanguinea, which must have washed up from under the kelp beds (too bad I did not get the entire plant in frame…). Second, a photo of Ulva with Chipolata weed Scytosiphon lomentaria. Third, the brown Divided net weed Dictyota dichotoma. Fourth, Slender wart weed Gracilaria gracilis. Fifth, False eyelash weed Calliblepharis jubata; this plant has grown quite large and has turned from dark red/brown to a much lighter brown. Sixth, the Falkenbergia stage of Harpoon weed Asparagopsis armata (see the third photo) on the right. Seventh, Red grape weed Gastroclonium ovatum. Finally, two photos of my favourite species the blue Bushy rainbow wrack Cystoseira tamariscifolia.