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

Unprecedented observations of one of the world's most intelligent invertebrates this past summer have prompted the naming of 2025 as “the year of the octopus” in a yearly report of UK coastal waters.

A Confluence of Factors Driving a Surge

An unusually warm winter followed by an exceptionally warm spring catalyzed a massive influx of common octopuses (*Octopus vulgaris*) to settle along England’s south coast, from Penzance in Cornwall to south Devon.

“The volume of octopuses caught was of the order of about over a dozen times what we would usually anticipate in this region,” commented an ocean conservation expert. “When we added up the numbers, nearly a quarter of a million octopuses were found in these waters this year – that’s a huge increase from what is typical.”

The Mediterranean octopus is found in British seas but usually so scarce it is rarely seen. A sudden increase is the result of a combination of a mild winter and favorable spring temperatures. Such favorable circumstances meant a higher survival rate for young, maybe aided by large numbers of spider crabs also recorded.

A Rare Phenomenon

The most recent occasion, such an octopus proliferation this significant was documented in the mid-20th century, with historical records indicating the one before that was in 1900.

The huge numbers of octopuses meant they could be frequently seen in shallow waters for the first time in living memory. Video footage show octopuses congregating together – they are usually solitary – and ambulating along the bottom on the tips of their limbs. One creature was even filmed grabbing an underwater camera.

“On my initial dive in that area this year I saw five octopuses,” they noted. “They are sizeable. We have two species in UK waters. The curled octopus is smaller, the size of a ball, but the *Octopus vulgaris* can be reaching impressive sizes.”

Predictions and Marine Joy

A second gentle winter going into 2026 could lead to a repeat event next year, because historically, in similar situations, the blooms have repeated for two years in a row.

“But, it's improbable, looking at history, that it will go on for a long time,” they said. “The ocean is full of surprises currently so it’s quite an unpredictable situation.”

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

• Highest-ever counts of gray seals seen in Cumbria.
• Record numbers of puffins on an island off Wales.
• A first-ever sighting of a rare sea slug in Yorkshire, normally residing farther south.
• A type of blenny found off the coast of a southern county for the first occasion.

A Note of Caution

The year had its low points, however. “The year was bookended by ecological challenges,” noted a conservation leader. “A major tanker collision in March and a spill of tonnes of plastic biobeads off the southern coast highlighted ongoing threats. Staff and volunteers are putting in immense work to safeguard and rehabilitate our shorelines.”