2025 Hailed as the 'Year of the Octopus' Off Britain's Southern Shores.

Exceptionally high observations of a supremely intelligent sea creature over the summer months have prompted the designation of 2025 as “the year of the octopus” in a seasonal assessment of the nation's marine environment.

A Perfect Storm Driving a Surge

A gentle winter followed by an exceptionally warm spring triggered unprecedented numbers of Mediterranean octopuses to take up residence along the southern coastline of England, across the southwestern peninsula.

“The scale of the catch was of the order of about over a dozen times what we would typically see in Cornish waters,” stated a marine conservation officer. “Based on the totals, nearly a quarter of a million octopuses were present in British seas this year – which is a significant rise from historical averages.”

*Octopus vulgaris* is found in UK waters but ordinarily in such small numbers it is seldom observed. A sudden increase is caused by a combination of gentle winter conditions and favorable spring temperatures. This perfect scenario meant a higher survival rate for young, possibly in part fuelled by significant populations of spider crabs also recorded.

A Historic Event

Previously, a population surge of this scale this significant was documented in the 1950s, with past documentation indicating the one before that was in the turn of the 20th century.

The sheer quantity of octopuses meant they could be frequently seen in shallow waters for a rare occurrence. Video footage show octopuses congregating together – unlike their typical solitary behavior – and moving along the bottom on the tips of their limbs. One creature was even recorded reaching for submarine recording equipment.

“During a first dive off the Lizard peninsula this year I saw multiple octopuses,” the specialist continued. “They are large specimens. Two kinds exist in UK waters. The curled octopus is smaller, the size of a ball, but these common octopuses can be reaching impressive sizes.”

Predictions and Marine Joy

A second gentle winter this coming winter could lead to another surge in 2026, because historically, in similar situations, events have occurred consecutively for two years in a row.

“Still, the chances are low, from previous blooms, that it will go on for a long time,” they said. “The ocean is full of surprises at the moment so it’s quite an unpredictable situation.”

The annual review also celebrated other “surprises, successes and joyful moments” along the coast, including:

• Highest-ever counts of grey seals recorded in Cumbria.
• Peak numbers of puffins on an island off Wales.
• The initial discovery of a rare sea slug in Yorkshire, usually found in the south-west.
• A type of blenny found off the coast of a southern county for the inaugural time.

A Note of Caution

The year had its low points, however. “The year was bookended by marine incidents,” said a head of marine conservation. “A major tanker collision in the North Sea and the release of tonnes of plastic biobeads off the Sussex coast served as stark reminders. Staff and volunteers are making huge efforts to defend and heal our marine habitats.”