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

Exceptionally high sightings of one of the world's most intelligent invertebrates this past summer have prompted the designation of 2025 as the year for octopuses in a seasonal assessment of Britain’s seas.

A Perfect Storm Driving a Surge

A mild winter and then a very warm springtime catalyzed a massive influx of Mediterranean octopuses to settle along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.

“The reported landings was of the order of about thirteen times what we would typically see in the waters around Cornwall,” commented a marine conservation officer. “Calculating the figures, approximately 233,000 octopuses were present in British seas this year – representing a massive jump from what is typical.”

The Mediterranean octopus is found in British seas but ordinarily in such small numbers it is seldom observed. A sudden increase is caused by the dual effect of gentle winter conditions and favorable spring temperatures. Such favorable circumstances meant a higher survival rate for young, potentially supported by significant populations of other marine life also recorded.

A Historic Event

Previously, such an octopus proliferation this significant was observed in 1950, with past documentation indicating the last bloom prior to that occurred in 1900.

The sheer quantity of octopuses meant they could be frequently seen in shallow waters for a rare occurrence. Diver videos show octopuses being sociable – they are usually solitary – and moving along the bottom on the tips of their limbs. One creature was even filmed grabbing submarine recording equipment.

“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. The curled octopus is smaller, the size of a ball, but the *Octopus vulgaris* can be up to a metre and a half wide.”

Looking Ahead & Coastal Highlights

Another mild winter heading into next year meant it was possible another surge in 2026, because based on records, in similar situations, events have occurred consecutively for two years in a row.

“But, it's improbable, looking at history, that it will become a permanent fixture,” they cautioned. “Marine life is unpredictable at the moment so it’s quite an unpredictable situation.”

The annual review also celebrated further encouraging coastal sightings along the coast, including:

• Highest-ever counts of grey seals observed in Cumbria.
• Peak numbers of the iconic seabirds on an island off Wales.
• The initial discovery of an unusual mollusc in a northern county, typically a southwestern species.
• A type of blenny spotted off the coast of a southern county for the first time.

A Note of Caution

Not everything was good news, however. “The period was framed by ecological challenges,” stated an expert. “A major tanker collision in March and the release of industrial pellets off the southern coast served as stark reminders. Staff and volunteers are working tirelessly to safeguard and rehabilitate our coasts.”