Surge in Guernsey and Alderney of jellyfish native to Mediterranean

The crystal jellyfish, captured in Arch Bay, Alderney, is more commonly found in the Mediterranean

Blooms of a species of jellyfish usually found in the Mediterranean have been sighted around Alderney and Guernsey.

The aequorea victoria, also called the crystal jelly, prefers warmer waters.

But marine biologist Alex Purdie said "hundreds" were spotted in Alderney and Guernsey over the last week.

Mr Purdie, of Alderney Wildlife Trust, said: "It's an indicator of warmer seas."

He said: "It's generally a Mediterranean species but in just the last five years we've started to see them in the Channel Islands.

"And in the last week or so we have seen blooms."

He described the species as "beautiful" and said its sting was "not strong enough to hurt people".

This crystal jellyfish was spotted in Arch Bay, Alderney

"It's an indicator of warmer seas," Mr Purdie said, "we are getting species which wouldn't necessarily have been able to survive here before."

He said jellyfish were a good indicator of "unstable ecosystems".

"As it gets warmer we are likely to see weird things going on. We might also see other species of jellyfish pushed out."

Roland Gauvain, manager at the wildlife trust, said he had spotted "hundreds" of jellyfish while out on the water this week.

He said: "I'd not seen that before with that particular species."

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