2025 Proclaimed The Year for Octopuses Off Britain's Southern Shores.

Record-breaking encounters of one of the world's most intelligent invertebrates this past summer have led to the declaration of 2025 as the year for octopuses in an annual review of Britain’s seas.

Ideal Conditions Leading to an Explosion

A gentle winter followed by a remarkably hot spring catalyzed unprecedented numbers of common octopuses (*Octopus vulgaris*) to settle along the southern coastline of England, across the southwestern peninsula.

“The scale of the catch was approximately thirteen times what we would typically see in this region,” stated a marine life specialist. “When we added up the numbers, approximately 233,000 octopuses were found in UK waters this year – that’s a huge increase from what is typical.”

The common octopus is native to UK waters but ordinarily in such small numbers it is rarely seen. An explosive growth is caused by the dual effect of gentle winter conditions and a warm breeding season. This perfect scenario meant more larvae, possibly in part fuelled by significant populations of spider crabs noted in recent years.

A Rare Phenomenon

The most recent occasion, a population surge of this scale this significant was documented in the mid-20th century, with past documentation indicating the one before that happened in 1900.

The remarkable abundance of octopuses meant they could be frequently seen in nearshore environments for the first time in recent history. Diver videos show octopuses being sociable – unlike their typical solitary behavior – and “walking” along the seabed on the tips of their limbs. One creature was even filmed grabbing an underwater camera.

“During a first dive there this year I saw five of these creatures,” the officer added. “And these are big. There are two types in UK waters. The curled octopus is smaller, the size of a ball, but these common octopuses can be up to a metre and a half wide.”

Future Prospects and Other Surprises

Another mild winter going into 2026 suggests the potential another surge in 2026, because in the past, with such patterns, populations have surged again for two years running.

“But, it's improbable, based on past events, that it will go on for a long time,” they said. “But the sea keeps giving us surprises these days so it’s a very uncertain scenario.”

The assessment also noted additional positive marine news around the UK coastline, including:

• Unprecedented numbers of grey seals observed in Cumbria.
• Record numbers of the iconic seabirds on an island off Wales.
• The first recording of an unusual mollusc in a northern county, typically a southwestern species.
• A variable blenny spotted off the coast of Sussex for the inaugural time.

Environmental Concerns

Challenges were also present, however. “The calendar year was marked by ecological challenges,” stated an expert. “A major tanker collision in March and the release of tonnes of plastic biobeads off the Sussex coast were serious issues. Staff and volunteers are working tirelessly to protect and restore our coasts.”