2025 Hailed as The Year for Octopuses Off Britain's South Coast.

Record-breaking sightings of a remarkably clever cephalopod this past summer have led to the declaration of 2025 as “the year of the octopus” in a yearly report of Britain’s seas.

Ideal Conditions Driving a Surge

An unusually warm winter followed by a very warm springtime prompted unprecedented numbers of Mediterranean octopuses to take up residence along the shores from Cornwall to Devon, spanning the Cornish and Devonian coasts.

“The scale of the catch was roughly thirteen times what we would typically see in the waters around Cornwall,” stated a marine life specialist. “When we added up the numbers, approximately 233,000 octopuses were caught in UK waters this year – representing a massive jump from historical averages.”

The Mediterranean octopus is indigenous to British seas but ordinarily in such small numbers it is rarely seen. A population bloom is attributed to a combination of gentle winter conditions and favorable spring temperatures. Such favorable circumstances meant increased juvenile survival, potentially supported by abundant stocks of a favored prey species seen in the area.

An Uncommon Occurrence

Previously, an octopus bloom comparable was documented in the 1950s, with past documentation indicating the last bloom prior to that occurred in 1900.

The remarkable abundance of octopuses meant they could be frequently seen in shallow waters for a rare occurrence. Underwater recordings show octopuses gathering in groups – contrary to their normally lone nature – and moving along the bottom on their arm ends. One creature was even recorded reaching for a diver's camera.

“On my initial dive 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 smaller, football-sized, but these newcomers can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

If conditions remain mild heading into next year meant it was possible a repeat event next year, because based on records, under these conditions, events have occurred consecutively for two years in a row.

“Still, the chances are low, based on past events, that it will go on for a long time,” they said. “The ocean is full of surprises currently so it’s quite an unpredictable situation.”

The annual review also highlighted additional positive marine news across British shores, including:

• Unprecedented numbers of grey seals seen in one northern region.
• Peak numbers of puffins on an island off Wales.
• The initial discovery of an unusual mollusc in Yorkshire, usually found in the south-west.
• A type of blenny spotted off the coast of a southern county for the first occasion.

Not All Positive News

The year had its low points, however. “The year was bookended by ecological challenges,” said a head of marine conservation. “A significant shipping incident in March and the release of plastic pollution off the southern coast served as stark reminders. Conservation teams are making huge efforts to defend and heal our shorelines.”