Heaviest jellyfish on Earth filmed off Washington coast

Heaviest jellyfish on Earth filmed off Washington coast

The lion's mane jellyfish has an estimated maximum weight of more than 1,000kg. This videographer found one on a night dive in the Salish Sea.


An underwater videographer has shared enchanting footage of a lion’s mane jellyfish during a night dive in the Salish Sea – a marginal sea of the Pacific Ocean. The creature was so gigantic that it took him over a minute to find it after first spotting its trailing tentacles. 

“Several minutes into the dive, I noticed a long, thin tentacle trailing overhead, stretching far beyond my vision,” says underwater videographer John Roney on Instagram. “I followed it through the darkness for over a minute before coming upon a giant lion’s mane jellyfish.”

Underwater videographer John Roney filmed the huge lion's mane jellyfish on a night dive in the Salish Sea – a marginal sea between the US state of Washington and the Canadian province of British Columbia. Credit: John Roney

His footage shows the enormous jellyfish pulsing through the dark water as marine snow drifts gently downwards behind it. The artful footage lingers on the animal’s brightly coloured tentacles, which "have these deep, vibrant orange, purple and crimson colours that I love to film,” he says.

Lion’s mane jellies are one of the world’s largest species of jellyfish and they have a nasty sting. “Fair warning,” says Roney. “This is a jellyfish you definitely don’t want to touch.”

According to the Guinness World Records, the lion's mane jellyfish has been estimated to have a maximum weight exceeding one tonne, making it the heaviest jellyfish species in the world. Credit: John Roney

Image and video credit: John Roneyroneydives.com

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