2025 Proclaimed 'The Octopus Year' Along England's South Coast.

Exceptionally high sightings of a remarkably clever cephalopod this past summer have prompted the naming of 2025 as the octopus's year in a seasonal assessment of UK coastal waters.

A Confluence of Factors Driving a Surge

An unusually warm winter followed by a very warm springtime triggered unprecedented numbers of common octopuses (*Octopus vulgaris*) to take up residence along the shores from Cornwall to Devon, spanning the Cornish and Devonian coasts.

“The reported landings was of the order of about over a dozen times what we would typically see in Cornish waters,” explained an ocean conservation expert. “When we added up the numbers, around 233 thousand octopuses were present in UK waters this year – which is a significant rise from the norm.”

The common octopus is indigenous to British seas but usually so scarce it is rarely seen. An explosive growth is caused by the dual effect of a mild winter and favorable spring temperatures. Such favorable circumstances meant increased juvenile survival, possibly in part fuelled by significant populations of a favored prey species also recorded.

An Uncommon Occurrence

The last time, such an octopus proliferation this significant was observed in 1950, with past documentation indicating the previous major event was in 1900.

The huge numbers of octopuses meant they could be frequently seen in nearshore environments for the first time in recent history. Diver videos show octopuses gathering in groups – unlike their typical solitary behavior – and moving along the ocean floor on the tips of their limbs. One individual was even seen investigating an underwater camera.

“During a first dive off the Lizard peninsula this year I saw five octopuses,” the officer added. “They are sizeable. Two kinds exist in UK waters. The curled octopus is quite small, the size of a ball, but the *Octopus vulgaris* can be up to a metre and a half wide.”

Future Prospects and Other Surprises

Another mild winter heading into next year suggests the potential a repeat event next year, because historically, in similar situations, the blooms have repeated for two years in a row.

“But, it's improbable, based on past events, that it will become a permanent fixture,” they said. “Marine life is unpredictable at the moment so it’s quite an unpredictable situation.”

The assessment also highlighted other “surprises, successes and joyful moments” along the coast, including:

• A record number of gray seals observed in one northern region.
• Peak numbers of the iconic seabirds on an island off Wales.
• The initial discovery of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A type of blenny discovered off the coast of a southern county for the first time.

A Note of Caution

Not everything was good news, however. “The calendar year was marked by marine incidents,” noted a conservation leader. “A major tanker collision in the North Sea and the release of tonnes of plastic biobeads off the southern coast served as stark reminders. Dedicated individuals are putting in immense work to safeguard and rehabilitate our coasts.”