2025 Proclaimed the 'Year of the Octopus' Off England's Southern Shores.

Record-breaking sightings of one of the world's most intelligent invertebrates this past summer have led to the declaration of 2025 as “the year of the octopus” in an annual review of Britain’s seas.

Ideal Conditions Driving a Surge

A gentle winter followed by a very warm springtime prompted a huge population of Mediterranean octopuses to establish themselves along the shores from Cornwall to Devon, across the southwestern peninsula.

“The volume of octopuses caught was approximately over a dozen times what we would typically see in the waters around Cornwall,” commented a marine life specialist. “Based on the totals, nearly a quarter of a million octopuses were caught in British seas this year – which is a significant rise from historical averages.”

The common octopus is native to UK waters but ordinarily in such small numbers it is seldom observed. A sudden increase is the result of a combination of gentle winter conditions and favorable spring temperatures. These ideal conditions meant increased juvenile survival, possibly in part fuelled by abundant stocks of other marine life noted in recent years.

An Uncommon Occurrence

The most recent occasion, an octopus bloom this significant was recorded in 1950, with archival data indicating the previous major event occurred in the turn of the 20th century.

The remarkable abundance of octopuses meant they could be frequently seen in shallow waters for a rare occurrence. Underwater recordings show octopuses being sociable – contrary to their normally lone nature – and moving along the bottom on their tentacle tips. One creature was even recorded reaching for an underwater camera.

“On my initial dive in that area this year I saw five of these creatures,” the specialist continued. “And these are big. We have two species in these waters. One species is smaller, football-sized, but the *Octopus vulgaris* can be up to a metre and a half wide.”

Looking Ahead & Coastal Highlights

Another mild winter going into 2026 meant it was possible another surge next year, because historically, under these conditions, populations have surged again for two consecutive years.

“But, it's improbable, looking at history, that it will persist indefinitely,” they said. “Marine life is unpredictable at the moment so it’s quite an unpredictable situation.”

The annual review also highlighted further encouraging coastal sightings around the UK coastline, including:

• Highest-ever counts of gray seals recorded in one northern region.
• Exceptional populations of the iconic seabirds on Skomer.
• The first recording of the *Capellinia fustifera* nudibranch in Yorkshire, typically a southwestern species.
• A Mediterranean fish species discovered off the coast of Sussex for the inaugural time.

Environmental Concerns

The year had its low points, however. “The year was bookended by environmental disasters,” noted a conservation leader. “A major tanker collision in March and the release of tonnes of plastic biobeads off the Sussex coast served as stark reminders. Staff and volunteers are working tirelessly to protect and restore our marine habitats.”