2025 Proclaimed 'The Octopus Year' Off England's Southern Shores.

Exceptionally high encounters of a supremely intelligent sea creature during the summer season have resulted in the declaration of 2025 as the octopus's year in a seasonal assessment of UK coastal waters.

A Perfect Storm Driving a Surge

An unusually warm winter and then an exceptionally warm spring prompted a massive influx of Mediterranean octopuses to establish themselves along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.

“The reported landings was of the order of about over a dozen times what we would usually anticipate in the waters around Cornwall,” stated a marine conservation officer. “Based on the totals, approximately 233,000 octopuses were present in British seas this year – which is a significant rise from historical averages.”

The Mediterranean octopus is found in these waters but ordinarily in such small numbers it is rarely seen. A sudden increase is the result of the dual effect of a mild winter and a warm breeding season. Such favorable circumstances meant a higher survival rate for young, possibly in part fuelled by abundant stocks of a favored prey species noted in recent years.

An Uncommon Occurrence

The most recent occasion, an octopus bloom this significant was observed in the mid-20th century, with past documentation indicating the one before that happened in the turn of the 20th century.

The huge numbers of octopuses meant they could be frequently seen in shallow waters for the first time in living memory. Underwater recordings show octopuses gathering in groups – they are usually solitary – and “walking” along the seabed on their tentacle tips. One individual was even seen investigating a diver's camera.

“The first time I dived in that area this year I saw five octopuses,” the officer added. “They are sizeable. Two kinds exist in the region. The curled octopus is rather small, football-sized, but these common octopuses can be reaching impressive sizes.”

Future Prospects and Other Surprises

A second gentle winter going into 2026 suggests the potential a second bloom in 2026, because in the past, with such patterns, the blooms have repeated for two consecutive years.

“But, it's improbable, looking at history, that it will become a permanent fixture,” they cautioned. “Marine life is unpredictable currently so it’s quite an unpredictable situation.”

The report also noted other “surprises, successes and joyful moments” across British shores, including:

• A record number of grey seals observed in Cumbria.
• Exceptional populations of the iconic seabirds on Skomer.
• The first recording of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A Mediterranean fish species found off the coast of a southern county for the first occasion.

Environmental Concerns

The year had its low points, however. “The year was bookended by marine incidents,” said a head of marine conservation. “A major tanker collision in the North Sea and a spill of industrial pellets off the Sussex coast highlighted ongoing threats. Conservation teams are putting in immense work to defend and heal our marine habitats.”