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

Record-breaking observations of one of the world's most intelligent invertebrates over the summer months have resulted in the naming of 2025 as the octopus's year in an annual review of UK coastal waters.

Ideal Conditions Leading to an Explosion

A gentle winter followed by an exceptionally warm spring catalyzed a huge population of common octopuses (*Octopus vulgaris*) to establish themselves along England’s south coast, spanning the Cornish and Devonian coasts.

“The reported landings was of the order of about over a dozen times what we would normally expect in this region,” stated a marine life specialist. “Based on the totals, around 233 thousand octopuses were found in UK waters this year – that’s a huge increase from the norm.”

The common octopus is indigenous to these waters but ordinarily in such small numbers it is rarely seen. An explosive growth is attributed to a combination of gentle winter conditions and favorable spring temperatures. These ideal conditions meant more larvae, potentially supported by abundant stocks of spider crabs seen in the area.

An Uncommon Occurrence

The last time, such an octopus proliferation comparable was observed in 1950, with past documentation indicating the one before that was in 1900.

The sheer quantity of octopuses meant they could be easily spotted in nearshore environments for a rare occurrence. Diver videos show octopuses gathering in groups – contrary to their normally lone nature – and “walking” along the bottom on the tips of their limbs. One creature was even seen investigating a diver's camera.

“The first time I dived in that area this year I saw five of these creatures,” the officer added. “They are sizeable. There are two types in these waters. One species is rather small, football-sized, but these newcomers can be up to a metre and a half wide.”

Predictions and Marine Joy

If conditions remain mild heading into next year suggests the potential another surge in 2026, because historically, under these conditions, populations have surged again for two years in a row.

“However, it is unlikely, based on past events, that it will become a permanent fixture,” they cautioned. “Marine life is unpredictable at the moment so it’s hard to forecast.”

The annual review also highlighted additional positive marine news around the UK coastline, including:

• A record number of grey seals recorded in one northern region.
• Exceptional populations of puffins on an island off Wales.
• A first-ever sighting of a rare sea slug in a northern county, usually found in the south-west.
• A type of blenny found off the coast of Sussex for the inaugural time.

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 March and an accidental discharge of industrial pellets off the southern coast highlighted ongoing threats. Staff and volunteers are putting in immense work to defend and heal our shorelines.”