2025 Declared The Year for Octopuses Off Britain's Southern Shores.
Exceptionally high sightings of a supremely intelligent sea creature over the summer months have resulted in the naming of 2025 as the year for octopuses in an annual review of the nation's marine environment.
A Confluence of Factors Driving a Surge
A mild winter followed by a remarkably hot spring catalyzed unprecedented numbers of Mediterranean octopuses to settle along the shores from Cornwall to Devon, spanning the Cornish and Devonian coasts.
“The scale of the catch was of the order of about over a dozen times what we would usually anticipate in the waters around Cornwall,” stated a marine life specialist. “Calculating the figures, nearly a quarter of a million octopuses were caught in these waters this year – that’s a huge increase from what is typical.”
The common octopus is indigenous to UK waters but usually so scarce it is rarely seen. A sudden increase is caused by a combination of a mild winter and favorable spring temperatures. Such favorable circumstances meant increased juvenile survival, possibly in part fuelled by large numbers of spider crabs noted in recent years.
A Rare Phenomenon
The most recent occasion, an octopus bloom this significant was recorded in the 1950s, with archival data indicating the one before that was in 1900.
The sheer quantity of octopuses meant they could be readily observed in shallow waters for the first time in recent history. Diver videos show octopuses being sociable – they are usually solitary – and moving along the seabed on the tips of their limbs. One individual was even recorded reaching for an underwater camera.
“The first time I dived there this year I saw multiple octopuses,” they noted. “They are large specimens. We have two species in UK waters. One species is smaller, about the size of a football, but these common octopuses can be with a span of 1.5 meters.”
Predictions and Marine Joy
Another mild winter going into 2026 suggests the potential a second bloom next year, because based on records, in similar situations, the blooms have repeated for two consecutive years.
“However, it is unlikely, looking at history, that it will persist indefinitely,” they said. “The ocean is full of surprises at the moment so it’s hard to forecast.”
The assessment also noted further encouraging coastal sightings around the UK coastline, including:
- Highest-ever counts of grey seals seen in Cumbria.
- Exceptional populations of puffins on a Welsh island.
- The initial discovery of an unusual mollusc in Yorkshire, normally residing farther south.
- A variable blenny found off the coast of Sussex for the first time.
Environmental Concerns
Not everything was good news, however. “The year was bookended by ecological challenges,” stated an expert. “A significant shipping incident in March and an accidental discharge of industrial pellets off the southern coast served as stark reminders. Conservation teams are putting in immense work to defend and heal our coasts.”