SCUBA News~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Welcome. This month, we're charting a course from the hammerhead-heavy currents of the Galapagos to the vibrant, coral-fringed pinnacles of Thailand. We also have a curated selection of liveaboard deals alongside a closer look at the stinging beauty of the snakelocks anemone. Plus, stay informed with our roundup of the latest global diving news.
You can download SCUBA News as a pdf. Personalised scuba diving itineraries, just for you: choose Turkey or Italy  And not just diving, visit Pompei or other historical sites. Everything tailored to your requirements. Talk to Aldo today, asbruno11@aol.com or WhatsApp 07713 611206, and plan your perfect trip. What's New at SCUBA Travel?
Liveaboard Diving Offers: Dive for LessTravel feels a little less predictable right now, routes are changing and many are wondering if their flights will be cancelled. A number of boats are offering extra reassurance through flexible rescheduling options or future travel credit if plans need to change. Also, make sure you have travel insurance from the moment you book your flight or liveaboard.
Snakelocks: Medusa of the shallowsThe snakelocks anemone is one of the most distinctive invertebrates you'll encounter on a dive in European waters. Its long, sinuous tentacles sway continuously in the current, unable to retract like most other anemones
The name snakelocks comes from the idea that each tentacle looks like a snake, and that together they look like locks of hair as in the Greek myth of Medusa. Different colours depending on depthThe most beautiful are green with pink tips to the tentacles. These live in shallow waters with plenty of sunlight. Like corals, their colour is given by symbiotic algae - specifically zooxanthellae - within the anemones' tissues. The algae gain protection and nutrient salts whilst the anemone benefits from organic compounds synthesised by the algae using sunlight as the energy source. When the anemones are deeper, they have less algae because of the lack of light and these appear a dull dark grey colour.
Turn to Face the SunPreviously only known in plants, new research reveals that on bright days the Snakelocks Anemones track the sun - similar to sunflowers on land. Whilst remaining in one place, they face east at dawn turning towards the sun throughout the day until facing west at dusk. This promotes light absorption to maximise photosynthesis of their algae. They can also, though, on extremely sunny days in rock pools for example, turn away from the sun to reduce the risk of exposure to excessive sunlight.
Active PredatorAlthough they get much nutrition from their algae, they are also carnivores. When a small animal touches a tentacle, it triggers thousands of specialised stinging cells called nematocysts. These inject venom into the unfortunate prey that paralyses or kills it. The tentacles then work together to transport the immobilised animal toward the central mouth. Safe haven for other species like Shrimps and CrabsLook closely into the tentacles on your next dive and you'll often find another creature living there. The anemone hosts small spider crabs in the Inachus genus and Periclimenes shrimps within the protective tentacles. Why are these not attacked by the anemone? Well, the prompt from the anemone to attack is not just mechanical. It also depends on chemical signals. The crustaceans living with the anemones acquire protection by gradually increasing contact with the tentacles. Some crabs even break off parts of the tentacle and attach it to themselves.
Reproduction: The Power of the CloneYou might see dense carpets of the snakelocks anemones. This is because they most commonly reproduce asexually, splitting in half longitudinally and growing into two new anemones.
When they reproduce sexually, they don't have free swimming larvae but grow wherever the fertilised egg first lands. Are they Dangerous?While beautiful, the Snakelocks is one of the few European anemones capable of penetrating human skin and giving you a nasty sting. In severe cases this causes intense pain and skin lesions which sometimes last for months. No common treatments - such as vinegar, ammonia or baking soda - work. In fact these provoke a further discharge of stinging cells making everything worse. The immediate treatment is to:
(According to the US National Library of Medicine) The best way to prevent accidental contact is to always wear protective clothing when diving or swimming around the anemones. Where to see themThe snakelocks anemone (Anemonia viridis) is permanently attached to hard substrates throughout its range - from the Azores and Mediterranean north to the Irish Sea and Scandinavian waters. You'll find it most abundantly in surge channels, on rocky reefs and in shallow seaweed-rich areas, typically in well-lit water down to around 20 metres. A Delicacy at RiskSnakelocks anemones are a delicacy in southern Spain. Known as ortiguillas de mar or little sea nettles, the whole animal is coated in flour and fried in hot oil. However, over-harvesting and expansion of a Pacific invasive brown seaweed (Rugulopteryx okamurae) has left local stocks of the anemone in a critical state, leading to authorities closing the fishery indefinitely.
Another threat to the anemones globally are microplastics. They are particularly at risk due to their proximity to the coastline, non-selective feeding and sedentary habit. The anemones both eat the microplastics and trap them in the mucus of their tentacles. Mucus production has been suggested as a possible stress response which may perform a cleaning and defence. Anemones weakened by bleaching are also more susceptible to microplastics. Next time you're diving along the west coast of Europe, or the Mediterranean, look out for these interesting creatures. Phylum: Cnidaria > Subphylum: Anthozoa > Class: Hexacorallia > Order: Actiniaria > Suborder: Enthemonae > Superfamily: Actinioidea > Family: Actiniidae > Subfamily: Anthiinae > Genus: Anemonia > Species: Anemonia viridis References
Porro, B. et al. The many faced symbiotic snakelocks anemone (Anemonia viridis, Anthozoa): host and symbiont genetic differentiation among colour morphs. Heredity 124, 351-366 (2020). Landmann, S. et al. Field experiments on individual adaptation of the spider crab Inachus phalangium to its sea anemone host Anemonia viridis in the northern Adriatic Sea. Mediterranean Marine Science 17(2):333-339 (2016). Georgie Savage, et al. Uptake of microplastics by the snakelocks anemone (Anemonia viridis) is commonplace across environmental conditions, Science of The Total Environment, Volume 836, 2022, 155144, Naylor P, Great British Marine Animals, 2021. Diving news from around the World
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