Britain has seen a dramatic increase in the sightings of giant jellyfish, specifically barrel jellyfish, with an overall rise of 32 percent over the past year and a spike of 400 percent this September compared to the same period in 2022, according to data from the UK Marine Conservation Society. These enormous aquatic creatures, often appearing ghostly white, can grow up to a meter in diameter, 1.5 meters in length, and can weigh up to 75 pounds. While not harmful to humans, these jellyfish can continue to sting even after death, typically washing up on shores during May and June.
Despite their increasing presence, barrel jellyfish only ranked sixth in the most frequent jellyfish species spotted back in 2022. The reason behind their sudden population surge remains unclear, though environmental factors are suspected to be at play, according to the Conservation Society. Other commonly sighted species include the lion’s mane and moon jellyfish, both boasting a more painful sting than the barrel, though not posing a significant threat to humans.
The Society recorded a total of 1,737 jellyfish sightings over the 12 month period ending in September, with 11 percent of these sightings attributable to blooms of 100 jellyfish or more. The increasing numbers highlight the fluctuating ecosystem dynamics in the UK’s waters, especially amid the pressing global environmental changes.
