2025 Declared 'The Octopus Year' Along Britain's Southern Shores.

Unprecedented encounters of a remarkably clever cephalopod during the summer season have led to the declaration of 2025 as the octopus's year in a seasonal assessment of UK coastal waters.

A Confluence of Factors Driving a Surge

A gentle winter and then a remarkably hot spring triggered a massive influx of common octopuses (*Octopus vulgaris*) to take up residence along England’s south coast, spanning the Cornish and Devonian coasts.

“The reported landings was of the order of about 13 times what we would normally expect in Cornish waters,” explained an ocean conservation expert. “When we added up the numbers, approximately 233,000 octopuses were present in UK waters this year – representing a massive jump from historical averages.”

The Mediterranean octopus is indigenous to these waters but ordinarily in such small numbers it is seldom observed. A sudden increase is caused by a combination of gentle winter conditions and favorable spring temperatures. These ideal conditions meant increased juvenile survival, possibly in part fuelled by abundant stocks of spider crabs also recorded.

A Historic Event

The most recent occasion, an octopus bloom comparable was observed in 1950, with archival data indicating the last bloom prior to that happened in 1900.

The sheer quantity of octopuses meant they could be readily observed in shallow waters for the first time in living memory. Diver videos show octopuses gathering in groups – they are usually solitary – and moving along the ocean floor on their arm ends. One individual was even filmed grabbing an underwater camera.

“The first time I dived there this year I saw multiple octopuses,” the specialist continued. “And these are big. We have two species in the region. One species is smaller, the size of a ball, but these newcomers can be with a span of 1.5 meters.”

Looking Ahead & Coastal Highlights

Another mild winter heading into next year suggests the potential a repeat event in 2026, because in the past, under these conditions, events have occurred consecutively for two years in a row.

“But, it's improbable, from previous blooms, that it will go on for a long time,” they cautioned. “Marine life is unpredictable these days so it’s hard to forecast.”

The report also highlighted other “surprises, successes and joyful moments” around the UK coastline, including:

• Highest-ever counts of grey seals observed in one northern region.
• Record numbers of the iconic seabirds on a Welsh island.
• A first-ever sighting of the *Capellinia fustifera* nudibranch in a northern county, typically a southwestern species.
• A Mediterranean fish species spotted off the coast of Sussex for the first time.

Not All Positive News

Challenges were also present, however. “The calendar year was marked by environmental disasters,” noted a conservation leader. “A major tanker collision in the North Sea and an accidental discharge of industrial pellets off the southern coast highlighted ongoing threats. Conservation teams are putting in immense work to safeguard and rehabilitate our shorelines.”