Fewer jellyfish have been spotted in UK waters this year although recent warmer weather could bring out more blooms of the sea creatures, conservationists have said.
While sightings are down in the UK, visitors to Spain’s Costa del Sol have been warned of massive blooms of mauve stinger jellyfish which have left many people requiring treatment for their powerful stings.
This time last year some parts of UK seas were like a jellyfish soup with large blooms of thousands of the creatures reported, the Marine Conservation Society (MCS) said.
But according to the society’s national jellyfish survey, far fewer have been spotted this year, with most of the sightings in the west coast of the UK. Barrel, moon and blue jellyfish have been seen, as have large numbers of compass jellyfish which were spotted in the South West in late July.
The unusual weather might have affected jellyfish life cycles at sea, the MCS said. Weeks of heavy rain this summer also kept people away from beaches and the sea, so fewer reports have been coming in, although regular jellyfish recorders also report seeing far fewer this year.
In the last week sunnier weather and the beginning of the school holidays prompted more reports of jellyfish, and the MCS is calling on people to report their sightings.
The national survey aims to find out where and when jellyfish show up around the UK as part of efforts to learn more about critically endangered leatherback turtles which migrate to British waters to feed on their favourite food each summer.
Jellyfish also act as “thermometers” because they indicate the seas’ health levels. Their increase is linked to overfishing, pollution and climate change.
MCS biodiversity programme manager Dr Peter Richardson said: “Jellyfish are great opportunists and take advantage if the conditions at sea are favourable to them. They are the thermometers of the oceans because jellyfish populations are indicators of the health of our seas.
“There is now strong evidence that jellyfish blooms are increasing in some parts of the world and this has been linked to overfishing and pollution, while climate change may also be affecting the seas in their favour. The rise of the jellyfish is telling us that we must take better care of our seas.”