RARE SIGHTING
Watch incredible moment octopus changes colour on Welsh beach as swarms of creatures invade UK shores
Discover the science behind octopi changing colour in the box below
RARELY seen footage of an octopus changing colour has been captured in a perhaps unlikely location: the shores of Wales.
It follows the biggest boom in octopi numbers in the UK for decades.
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The video was recorded by the Marine Conservation Society’s Project Assistant Ciara Taylor on Menai Bridge beach, Anglesey.
It shows several white tentacles wriggling out from beneath a rock.
As the octopus reveals its head, its skin quickly changes to orange.
“I met two other young people who were rockpooling and one of them saw some tentacles sticking out from under a rock," Taylor explained.
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"They shouted over to me, so I ran over, and then we waited.
"It eventually came out and started crawling back towards the sea. We couldn't believe it.
"It was an amazing reminder of the beautiful wildlife we have in North Wales and why we need to protect it.”
An octopus changes colour to better match their skin to different rocks and corals in an effort to hide itself from predators.
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While Welsh shores are far from the tropics where some might expect to see octopi - they are apparently more common than people think.
Angus Jackson, Seasearch Data Officer at the Marine Conservation Society, said: “Curled octopus are found here all the time, and we get a handful of records every year.
"In contrast, we very seldom receive records for Mediterranean or common octopus."
The summer and autumn of 2022 were fascinating exceptions, where there appeared to be a boom in the population of common octopus, and we received many records
Angus Jackson, Seasearch Data Officer at the Marine Conservation Society
Octopi numbers jumped in 2022, according to the Marine Conservation Society’s Seasearch programme, which asks rockpoolers, snorkellers and divers to record marine life.
Experts reckon the conditions were just right that year for octopi to thrive, as the species doesn't typically live longer than a year.
"The summer and autumn of 2022 were fascinating exceptions, where there appeared to be a boom in the population of common octopus, and we received many records," Jackson added.
"Such booms have been noted in the past, but not for several decades.”
Recordings of octopi remained high last year, but not quite as high as the year prior.
The science behind octopi changing colour
Let's imagine an octopus feels under threat.
It uses its eyes to see the darkness, texture and layout of a scene it's in.
Although it can only see in grey, it uses its pupils distort light to get a rough idea of colour.
That information is then sent from its brain to the eight arm-brains that add colour from thousands of cells beneath its skin.
These cells are called chromatophores, and each of them has a tiny sac filled with either a red, orange, brown, yellow or black pigment.
Under the chromatophores is another layer of cells called iridophores, and these can reflect light back up through the octopus' skin to make colours look brighter.
All octopi lack blue and green pigment.
Instead, they use the reflective capabilities of their iridophore cells to add shades of blue and green to their skin.
Beyond colouration, the octopus can then make its skin match the texture of its surroundings - allowing for an even better disguise.
Using small muscle bundles called papillae, the octopus can make its skin bumpy or smooth as needed.
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