Photography during my last snorkel was a bit frustrating as I could not get my strobes to work. Luckily I was saved by a subject that did not require any extra light: beautiful translucent crystal jellies slowly pulsating near the surface. Crystal jellyfish are not true jellyfish (these belong in the Class Scyphozoa), but hydromedusae (Class Hydrozoa) which have a polyp stage in their lifecycle that bud of these sexual medusae. They are difficult to identify to species level so I keep it to Aequorea sp. I saw a few, around 10 cm in diameter, and had fun diving under them and get them in front of the afternoon sun.
Tag Archives: jellies
Portuguese Man O’ War at Gunwalloe Church Cove and Dollar Cove
The weather today was pretty bad, but it was still very nice to go for a quick stroll on the beach; we chose a new destination: Gunwalloe near Helston. The beach and cliffs here are more reminiscent of some of the North Coast spots, quite barren. At the moment, Facebook and Instagram are overflowing with pretty pictures of washed up Portuguese man o’ wars (or Portuguese men o’ war?) in Cornwall, but we only saw two small shrivelled up ones (at Holywell Beach) so far. It was therefore great to see ten or so on the high tide strand line at Dollar Cove and Gunwalloe Church Cove. The smaller ones measured only five cm or so, with the largest one close to 20 cm (the size refers to the pasty-shaped, gas-filled float or pneumatophore). Unlike true jellyfish, which can move by contracting muscles around their bell, the Portuguese man o’ War (Physalia physalis) just sails. More amazingly, they actually are not individuals but colonies comprised of different, specialized individuals (it is getting late writing this, so I will lazily refer to Wikipedia). Stunning colours and truly great finds!
Swanpool
OK, as I mentioned in the last post, I had been on three dives before my exceptional viz snorkel session but did not have the opportunity to post pictures. So here goes for the first dive at Swanpool with Thomas Daguerre. Swanpool is a nice little beach but I was sceptical about it, as it is mainly, well, beach. Thomas wanted to try to find some sand-dwelling creatures though and I was up for trying something new so in we went. See him at work below in some seriously murky water! 
Again, spider crabs were common, sitting still but running away when getting closer, stirring up the sand. There is some sparse seagrass, arranged in thickets parallel to the strandline, some Sand mason worms Lanice conchilega can be seen in the foreground. A Spiny starfish Marthasterias glacialis was eating up a Pod razor shell Ensis siliqua. A little swimming crab hid in the sand, not sure which species.
Also, jelly season has started, I saw several Northern Comb Jellies Beroe cucumis. They are exquisitely beautiful and very hard to focus on, which makes for a photographers nightmare. Apart from a Compass jellyfish, I noticed a Blue jellyfish Cyanea lamarcki. It appears to have two parasites, which could be the amphipod Hyperia galba. All in all not a bad dive. Also, I found a frisbee and a decent pair of sunglasses!
An Bollenessor 