2025 Proclaimed The Year for Octopuses Off England's South Coast.

Unprecedented encounters of one of the world's most intelligent invertebrates this past summer have prompted the naming of 2025 as the octopus's year in a seasonal assessment of UK coastal waters.

A Perfect Storm for a Population Boom

An unusually warm winter and then a remarkably hot spring catalyzed unprecedented numbers of *Octopus vulgaris* to take up residence along the shores from Cornwall to Devon, spanning the Cornish and Devonian coasts.

“The scale of the catch was of the order of about 13 times what we would normally expect in Cornish waters,” commented an ocean conservation expert. “When we added up the numbers, nearly a quarter of a million octopuses were present in UK waters this year – that’s a huge increase from historical averages.”

*Octopus vulgaris* is native to British seas but usually so scarce it is seldom observed. A population bloom is attributed to a combination of gentle winter conditions and a warm breeding season. Such favorable circumstances meant increased juvenile survival, maybe aided by large numbers of spider crabs also recorded.

An Uncommon Occurrence

The most recent occasion, such an octopus proliferation of this size was recorded in the mid-20th century, with past documentation indicating the last bloom prior to that was in 1900.

The sheer quantity of octopuses meant they could be readily observed in shallow waters for the first time in recent history. Video footage show octopuses congregating together – they are usually solitary – and “walking” along the ocean floor on their arm ends. One creature was even filmed grabbing a diver's camera.

“The first time I dived off the Lizard peninsula this year I saw five octopuses,” the officer added. “They are sizeable. There are two types in these waters. The curled octopus is rather small, about the size of a football, but the *Octopus vulgaris* can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

Another mild winter going into 2026 suggests the potential another surge next year, because based on records, under these conditions, the blooms have repeated for two years running.

“However, it is unlikely, based on past events, that it will persist indefinitely,” they stated. “The ocean is full of surprises currently so it’s a very uncertain scenario.”

The report also celebrated additional positive marine news along the coast, including:

• A record number of grey seals observed in one northern region.
• Peak numbers of puffins on a Welsh island.
• The initial discovery of an unusual mollusc in a northern county, typically a southwestern species.
• A variable blenny discovered off the coast of Sussex for the inaugural time.

Not All Positive News

Not everything was good news, however. “The period was framed by marine incidents,” said a head of marine conservation. “A major tanker collision in March and an accidental discharge of tonnes of plastic biobeads off the Sussex coast highlighted ongoing threats. Dedicated individuals are making huge efforts to protect and restore our shorelines.”