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

Record-breaking sightings of a supremely intelligent sea creature during the summer season have led to the declaration of 2025 as the octopus's year in an annual review of the nation's marine environment.

A Perfect Storm Driving a Surge

A mild winter coupled with an exceptionally warm spring prompted a huge population of Mediterranean octopuses to take up residence along the southern coastline of England, spanning the Cornish and Devonian coasts.

“The volume of octopuses caught was roughly thirteen times what we would normally expect in Cornish waters,” explained a marine conservation officer. “Based on the totals, approximately 233,000 octopuses were present in UK waters this year – which is a significant rise from the norm.”

*Octopus vulgaris* 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 gentle winter conditions and a warm breeding season. These ideal conditions meant a higher survival rate for young, possibly in part fuelled by large numbers of other marine life noted in recent years.

A Historic Event

The most recent occasion, such an octopus proliferation of this size was observed in the mid-20th century, with past documentation indicating the one before that was in 1900.

The huge numbers of octopuses meant they could be readily observed in coastal areas for the first time in recent history. Underwater recordings show octopuses congregating together – contrary to their normally lone nature – and moving along the seabed on their tentacle tips. One creature was even filmed grabbing a diver's camera.

“The first time I dived there this year I saw multiple octopuses,” they noted. “And these are big. Two kinds exist in these waters. The curled octopus is rather small, about the size of a football, but the *Octopus vulgaris* can be up to a metre and a half wide.”

Future Prospects and Other Surprises

If conditions remain mild this coming winter meant it was possible another surge in 2026, because based on records, under these conditions, events have occurred consecutively for two years in a row.

“However, it is unlikely, looking at history, that it will become a permanent fixture,” they cautioned. “But the sea keeps giving us surprises these days so it’s a very uncertain scenario.”

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

• Unprecedented numbers of grey seals recorded in Cumbria.
• Record numbers of puffins on an island off Wales.
• A first-ever sighting of a rare sea slug in a northern county, normally residing farther south.
• A variable blenny spotted off the coast of Sussex for the first time.

Not All Positive News

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 March and a spill of plastic pollution off the Sussex coast highlighted ongoing threats. Staff and volunteers are putting in immense work to protect and restore our shorelines.”