Paddleboarder stunned by huge jellyfish swarm in Hunstanton
A paddleboard instructor who came across a swarm of jellyfish said getting through them was "like paddling in porridge".
Andy Holland was training with a student about 1.5 miles (2.5km) off the Norfolk coast at Hunstanton on Wednesday.
While jellyfish are common off the coast, he said he had "never seen them in quantities like that".
Expert Sophie Negus said the "amazing" sighting was caused by warmer waters.
Mr Holland, a member of SUPS Life Hunstanton group, said he and his student had paddled out to try to find some "rough water" to practise on.
"We came across where the currents had just shoaled all the jellyfish together," he said.
"It was just like acres and acres of jellyfish. You see lots of jellyfish this time of year but... I've never seen them in quantities like that."
He said they ranged in size from "maybe the size of a dinner plate to maybe a beach ball - there were really some good-sized ones".
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"I think they were just swirling on top of the sand bars and it's one of those phenomenon where you just happen to be there at the same time."
He added: "We know what we're doing and obviously we were equipped for being out there."
Ms Negus, assistant curator, SEA LIFE Hunstanton, said such a large group was "absolutely amazing" but not uncommon.
She added moon jellyfish normally feed towards the top of the water surface, but when, as is currently the case, "waters are hotter than average" it can negatively impact its swimming ability.
This means they are more likely to get caught up in currents and tides and end up in large numbers off Norfolk's coastline.
"Luckily, moon jellyfish do not have a strong enough sting to harm humans - so if anyone falls off their paddleboard they'll be safe," she said.
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