2025 Proclaimed 'The Octopus Year' Off Britain's Southern Shores.

Unprecedented encounters of a supremely intelligent sea creature over the summer months have led to the naming of 2025 as the year for octopuses in an annual review of UK coastal waters.

A Perfect Storm Driving a Surge

A mild winter coupled with a remarkably hot spring triggered a massive influx of common octopuses (*Octopus vulgaris*) to settle along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.

“The scale of the catch was approximately over a dozen times what we would usually anticipate in the waters around Cornwall,” commented a marine conservation officer. “When we added up the numbers, approximately 233,000 octopuses were caught in UK waters this year – representing a massive jump from historical averages.”

The common octopus is found in British seas but typically so rare it is infrequently encountered. A sudden increase is caused by a combination of gentle winter conditions and favorable spring temperatures. These ideal conditions meant more larvae, maybe aided by large numbers of other marine life also recorded.

An Uncommon Occurrence

The most recent occasion, a population surge of this scale comparable was documented in the 1950s, with past documentation indicating the previous major event was in the turn of the 20th century.

The sheer quantity of octopuses meant they could be readily observed in shallow waters for the first time in living memory. Video footage show octopuses congregating together – contrary to their normally lone nature – and “walking” along the ocean floor on the tips of their limbs. One creature was even seen investigating a diver's camera.

“The first time I dived off the Lizard peninsula this year I saw five of these creatures,” the officer added. “They are sizeable. Two kinds exist in the region. One species is smaller, about the size of a football, but these newcomers can be up to a metre and a half wide.”

Predictions and Marine Joy

If conditions remain mild going into 2026 suggests the potential another surge in 2026, because based on records, in similar situations, the blooms have repeated for two consecutive years.

“Still, the chances are low, based on past events, that it will go on for a long time,” they said. “But the sea keeps giving us surprises at the moment so it’s quite an unpredictable situation.”

The report also celebrated other “surprises, successes and joyful moments” across British shores, including:

• A record number of grey seals seen in Cumbria.
• Record numbers of the iconic seabirds on a Welsh island.
• The initial discovery of the *Capellinia fustifera* nudibranch in Yorkshire, normally residing farther south.
• A variable blenny spotted off the coast of Sussex for the first time.

Not All Positive News

Not everything was good news, however. “The year was bookended by environmental disasters,” noted a conservation leader. “A significant shipping incident in March and the release of tonnes of plastic biobeads off the southern coast were serious issues. Conservation teams are putting in immense work to defend and heal our shorelines.”