Record Year for Basking Sharks

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Full Screen Image – Basking Shark ©Nick Sidle

Wildlife tour operator Basking Shark Scotland has reported a record number of sightings, over 700 between April and October compared to 250 last year and 172 in 2013, mostly around the Inner Hebrides.

Basking Shark Scotland

The Basking Shark is the second largest living fish, smaller only than the Whale Shark, with the largest accurately measured individual being 12.27m (40.3 feet), making it way above even the Great White of mythic dimensions in ‘Jaws’. Basking Sharks are sometimes mistaken for Great Whites because of their size and are the basis for some of the reports of Great Whites there have been in UK waters over the years (whilst there are some that deserve serious consideration there are as yet no confirmed Great White sightings off the British Isles). They are however very different animals and are filter feeders straining out Plankton from seawater and so are of no risk to anyone. Great Whites are in no way the terrifying prospect portrayed in ‘Jaws’ but they do have to be treated with some respect and tragedies have of course happened, even if they are fortunately extremely rare.

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Full Screen Image – Great White Shark ©Nick Sidle

Nick

Marine Scotland Gallery

Marine Australia Gallery

Basking Shark -Cetorhinus maximus

Great White Shark – Carcharodon carcharias

 

Energy Saving

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Full Screen Image – Lion’s Mane Jellyfish, Ardmair Bay, Highland Scotland ©Nick Sidle

A new study published this month in the journal ‘Nature Communications’ completely rewrites ideas about jellyfish movement;

Suction-based propulsion as a basis for efficient animal swimming

What the scientists have discovered, as the name of their paper suggests, is that instead of pushing themselves along using positive pressure behind them, as in most propulsion systems including swimming, jellyfish (and Lampreys) create a lower pressure ahead of their direction of travel and so are sucked forwards and that this is one of the most energy efficient systems that can be achieved. In the long term, it could even provide a model for lower energy technologies to power ships and submarines. If we could master it, it might even be a way of raising human performance in Olympic swimming events but somehow I can’t see top athletes plunging into the pool gripping a high technology straw between their teeth any time soon. More sensibly though, given the insight, it could lead to a recognition of more efficient movements in human swimming although collectively we have as a species had quite a long time to get it right through trial and error, even without the research.

The Lion’s Mane is a jellyfish that can be seen regularly around the North West coast of Scotland. It is the species which is the villain in the Sherlock Holmes story ‘The Adventure of the Lion’s Mane’. Presumably since it is supposed to be a mystery at the start of the tale, Sir Arthur Conan Doyle relied on not enough of his readers making the connection from the title, apologies if I’ve given the game away for anyone who has not read it. A bonus piece of Sherlock Holmes trivia  for anyone who is interested, although that may be a limited audience, ‘The Adventure of the Lion’s Mane’ is one of only two stories written as being narrated by Holmes himself, not Dr Watson. The other is ‘The Adventure of the Blanched Soldier’.

Nick

Marine Scotland gallery

Lion’s Mane Jellyfish – Cyanea capillata

Who wants to live forever?

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Full Screen Image – Beadlet Anemone, Ardmair Bay, Highland Scotland ©Nick Sidle

A report in the BBC News Magazine quoting Professor Dan Rokhsar from the University of California, Berkeley notes the observation that Sea Anemones live a very long time and possibly even indefinitely, unless their luck runs out and they are eaten, poisoned or a similar disaster catches up with them.

BBC News – The creature with the key to immortality

The Professor of genetics points out that there are similarities in the genome structure of anemones and human beings despite their going back more than 700 million years. However, despite confirming that they do have a recognisable nervous system allowing them to respond to stimuli and function as predators, it does have to be accepted that they really only live for the moment. They do not have the complications of memories, culture and consciousness, so whilst they may be able to go on forever and can certainly regrow large parts of their structure on need, effective regeneration to preserve what we would say matters most still remains the sole preserve of a certain doctor with a police telephone box, unless of course what you care about preserving is your appearance and then even the anemones manage that. I’ve also acknowledged that they experience (or not as the case may be), luck. Perhaps the links with us are really strong after all.

Nick

Scotland Marine gallery

Beadlet Anemone – Actinia equina