2025 Declared The Year for Octopuses Off Britain's Southern Shores.

Exceptionally high observations of a supremely intelligent sea creature during the summer season have resulted in the designation of 2025 as the year for octopuses in a seasonal assessment of the nation's marine environment.

A Confluence of Factors Leading to an Explosion

A mild winter followed by a remarkably hot spring triggered a huge population of Mediterranean octopuses to establish themselves along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.

“The volume of octopuses caught was roughly 13 times what we would normally expect in Cornish waters,” explained a marine life specialist. “Based on the totals, approximately 233,000 octopuses were found in UK waters this year – which is a significant rise from historical averages.”

The common octopus is indigenous to these waters but typically so rare it is infrequently encountered. A population bloom is the result of a combination of a mild winter and a warm breeding season. These ideal conditions meant a higher survival rate for young, potentially supported by large numbers of spider crabs seen in the area.

A Historic Event

The most recent occasion, such an octopus proliferation of this size was observed in 1950, with historical records indicating the previous major event was in 1900.

The huge numbers of octopuses meant they could be easily spotted in nearshore environments for a rare occurrence. Underwater recordings show octopuses gathering in groups – they are usually solitary – and moving along the ocean floor on the tips of their limbs. One individual was even seen investigating an underwater camera.

“During a first dive off the Lizard peninsula this year I saw five of these creatures,” the officer added. “And these are big. There are two types in the region. The curled octopus is quite small, football-sized, but the *Octopus vulgaris* can be reaching impressive sizes.”

Predictions and Marine Joy

A second gentle winter heading into next year meant it was possible a second bloom next year, because based on records, with such patterns, populations have surged again for two years in a row.

“However, it is unlikely, looking at history, that it will become a permanent fixture,” they said. “But the sea keeps giving us surprises at the moment so it’s quite an unpredictable situation.”

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

• A record number of grey seals observed in one northern region.
• Exceptional populations of the iconic seabirds on an island off Wales.
• The first recording of the *Capellinia fustifera* nudibranch in Yorkshire, normally residing farther south.
• A type of blenny discovered off the coast of Sussex for the first time.

Environmental Concerns

The year had its low points, however. “The period was framed by environmental disasters,” said a head of marine conservation. “A major tanker collision in March and an accidental discharge of plastic pollution off the southern coast highlighted ongoing threats. Dedicated individuals are making huge efforts to defend and heal our shorelines.”