2025 Proclaimed the 'Year of the Octopus' Off England's South Coast.

Unprecedented sightings of one of the world's most intelligent invertebrates over the summer months have led to the naming of 2025 as the octopus's year in an annual review of Britain’s seas.

A Perfect Storm Leading to an Explosion

An unusually warm winter followed by a very warm springtime prompted unprecedented numbers of Mediterranean octopuses to settle along England’s south coast, across the southwestern peninsula.

“The reported landings was of the order of about thirteen times what we would usually anticipate in Cornish waters,” commented an ocean conservation expert. “Based on the totals, nearly a quarter of a million octopuses were present in British seas this year – that’s a huge increase from the norm.”

The common octopus is indigenous to these waters but usually so scarce it is infrequently encountered. A population bloom is attributed to the dual effect of a mild winter and a warm breeding season. This perfect scenario meant a higher survival rate for young, maybe aided by abundant stocks of spider crabs also recorded.

A Historic Event

The most recent occasion, an octopus bloom comparable was recorded in the 1950s, with archival data indicating the one before that occurred in the turn of the 20th century.

The sheer quantity of octopuses meant they could be easily spotted in nearshore environments for the first time in living memory. Diver videos show octopuses being sociable – unlike their typical solitary behavior – and ambulating along the seabed on their tentacle tips. One individual was even filmed grabbing a diver's camera.

“On my initial dive there this year I saw five octopuses,” the officer added. “They are sizeable. There are two types in the region. One species is smaller, football-sized, but these common octopuses can be up to a metre and a half wide.”

Predictions and Marine Joy

A second gentle winter this coming winter could lead to another surge the following year, because based on records, under these conditions, populations have surged again for two years in a row.

“However, it is unlikely, from previous blooms, that it will become a permanent fixture,” they cautioned. “Marine life is unpredictable these days so it’s quite an unpredictable situation.”

The assessment also highlighted other “surprises, successes and joyful moments” along the coast, including:

• A record number of gray seals seen in one northern region.
• Peak numbers of puffins on Skomer.
• A first-ever sighting of a rare sea slug in Yorkshire, usually found in the south-west.
• A variable blenny spotted off the coast of a southern county for the inaugural time.

A Note of Caution

Challenges were also present, however. “The calendar year was marked by ecological challenges,” stated an expert. “A major tanker collision in the North Sea and the release of plastic pollution off the southern coast served as stark reminders. Staff and volunteers are putting in immense work to safeguard and rehabilitate our coasts.”