2025 Declared 'The Octopus Year' Along Britain's South Coast.

Record-breaking observations of a supremely intelligent sea creature this past summer have led to the naming of 2025 as “the year of the octopus” in a seasonal assessment of UK coastal waters.

A Perfect Storm Leading to an Explosion

An unusually warm winter coupled with an exceptionally warm spring prompted unprecedented numbers of *Octopus vulgaris* to settle along England’s south coast, from Penzance in Cornwall to south Devon.

“The reported landings was of the order of about over a dozen times what we would typically see in the waters around Cornwall,” stated a marine life specialist. “Based on the totals, approximately 233,000 octopuses were found in these waters this year – representing a massive jump from historical averages.”

*Octopus vulgaris* is found in these waters but typically so rare it is infrequently encountered. A population bloom is the result of a combination of a mild winter and favorable spring temperatures. These ideal conditions meant increased juvenile survival, potentially supported by large numbers of spider crabs also recorded.

A Rare Phenomenon

The last time, an octopus bloom this significant was documented in 1950, with past documentation indicating the previous major event occurred in the turn of the 20th century.

The remarkable abundance of octopuses meant they could be frequently seen in nearshore environments for the first time in living memory. Diver videos show octopuses congregating together – they are usually solitary – and moving along the seabed on the tips of their limbs. One creature was even filmed grabbing a diver's camera.

“During a first dive there this year I saw five of these creatures,” they noted. “And these are big. We have two species in these waters. The curled octopus is rather small, the size of a ball, but the *Octopus vulgaris* can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

If conditions remain mild going into 2026 meant it was possible a repeat event in 2026, because in the past, in similar situations, populations have surged again for two consecutive years.

“But, it's improbable, looking at history, that it will persist indefinitely,” they said. “The ocean is full of surprises these days so it’s a very uncertain scenario.”

The annual review also highlighted other “surprises, successes and joyful moments” across British shores, including:

• Unprecedented numbers of grey seals recorded in Cumbria.
• Peak numbers of the iconic seabirds on Skomer.
• The initial discovery of the *Capellinia fustifera* nudibranch in Yorkshire, normally residing farther south.
• A type of blenny discovered off the coast of a southern county for the first occasion.

A Note of Caution

Not everything was good news, however. “The calendar year was marked by marine incidents,” said a head of marine conservation. “A major tanker collision in March and an accidental discharge of industrial pellets off the Sussex coast were serious issues. Conservation teams are making huge efforts to safeguard and rehabilitate our shorelines.”