2025 Declared 'The Octopus Year' Along England's South Coast.

Unprecedented sightings of a remarkably clever cephalopod over the summer months have prompted the declaration of 2025 as “the year of the octopus” in an annual review of UK coastal waters.

A Perfect Storm Leading to an Explosion

An unusually warm winter and then a very warm springtime catalyzed a massive influx of common octopuses (*Octopus vulgaris*) to take up residence along the southern coastline of England, across the southwestern peninsula.

“The volume of octopuses caught was approximately over a dozen times what we would usually anticipate in Cornish waters,” explained a marine conservation officer. “Based on the totals, nearly a quarter of a million octopuses were found in British seas this year – that’s a huge increase from the norm.”

The common octopus is native to these waters but ordinarily in such small numbers it is rarely seen. A population bloom is caused by the dual effect of gentle winter conditions and favorable spring temperatures. Such favorable circumstances meant increased juvenile survival, maybe aided by significant populations of a favored prey species also recorded.

A Historic Event

Previously, such an octopus proliferation of this size was recorded in 1950, with archival data indicating the previous major event occurred in the turn of the 20th century.

The remarkable abundance of octopuses meant they could be readily observed in shallow waters for a rare occurrence. Underwater recordings show octopuses congregating together – unlike their typical solitary behavior – and “walking” along the bottom on their arm ends. One individual was even recorded reaching for submarine recording equipment.

“The first time I dived there this year I saw multiple octopuses,” they noted. “They are large specimens. We have two species in these waters. One species is smaller, the size of a ball, but these newcomers can be up to a metre and a half wide.”

Future Prospects and Other Surprises

A second gentle winter heading into next year suggests the potential another surge the following year, because historically, in similar situations, populations have surged again for two years running.

“However, it is unlikely, from previous blooms, that it will persist indefinitely,” they said. “The ocean is full of surprises currently so it’s a very uncertain scenario.”

The annual review also celebrated other “surprises, successes and joyful moments” across British shores, including:

• A record number of gray seals recorded in one northern region.
• Exceptional populations of the iconic seabirds on an island off Wales.
• The initial discovery of the *Capellinia fustifera* nudibranch in Yorkshire, normally residing farther south.
• A variable blenny spotted off the coast of Sussex for the inaugural time.

A Note of Caution

The year had its low points, however. “The period was framed by ecological challenges,” stated an expert. “A major tanker collision in March and the release of tonnes of plastic biobeads off the southern coast were serious issues. Staff and volunteers are making huge efforts to protect and restore our shorelines.”