2025 Hailed as the 'Year of the Octopus' Off Britain's South Coast.

Exceptionally high encounters of a remarkably clever cephalopod over the summer months have led to the designation of 2025 as the year for octopuses in an annual review of UK coastal waters.

A Perfect Storm Leading to an Explosion

A mild winter and then a very warm springtime prompted a huge population of *Octopus vulgaris* to settle along England’s south coast, across the southwestern peninsula.

“The scale of the catch was approximately 13 times what we would normally expect in the waters around Cornwall,” commented a marine conservation officer. “When we added up the numbers, around 233 thousand octopuses were present in British seas this year – that’s a huge increase from the norm.”

The Mediterranean octopus is native to British seas but typically so rare it is seldom observed. A sudden increase is caused by a combination of a mild winter and favorable spring temperatures. This perfect scenario meant a higher survival rate for young, possibly in part fuelled by abundant stocks of spider crabs seen in the area.

A Historic Event

The most recent occasion, such an octopus proliferation of this size was recorded in the 1950s, with historical records indicating the last bloom prior to that happened in 1900.

The huge numbers of octopuses meant they could be easily spotted in coastal areas for the first time in living memory. Diver videos show octopuses congregating together – contrary to their normally lone nature – and moving along the ocean floor on their arm ends. One individual was even filmed grabbing a diver's camera.

“During a first dive in that area this year I saw five of these creatures,” they noted. “They are large specimens. There are two types in these waters. One species is smaller, about the size of a football, but these common octopuses can be up to a metre and a half wide.”

Future Prospects and Other Surprises

If conditions remain mild heading into next year could lead to a second bloom the following year, because historically, under these conditions, the blooms have repeated for two consecutive years.

“But, it's improbable, based on past events, that it will become a permanent fixture,” they stated. “The ocean is full of surprises at the moment so it’s a very uncertain scenario.”

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

• A record number of grey seals observed in one northern region.
• Peak numbers of the iconic seabirds on an island off Wales.
• The first recording of an unusual mollusc in Yorkshire, normally residing farther south.
• A type of blenny found off the coast of Sussex for the inaugural time.

Not All Positive News

Not everything was good news, however. “The year was bookended by marine incidents,” said a head of marine conservation. “A major tanker collision in the North Sea and the release of tonnes of plastic biobeads off the Sussex coast were serious issues. Dedicated individuals are putting in immense work to defend and heal our coasts.”