2025 Declared The Year for Octopuses Off England's South Coast.

Record-breaking observations of one of the world's most intelligent invertebrates over the summer months have led to the declaration of 2025 as the year for octopuses in a seasonal assessment of Britain’s seas.

A Perfect Storm Driving a Surge

An unusually warm winter followed by an exceptionally warm spring triggered unprecedented numbers of Mediterranean octopuses to establish themselves along the shores from Cornwall to Devon, across the southwestern peninsula.

“The reported landings was roughly over a dozen times what we would normally expect in this region,” commented a marine conservation officer. “When we added up the numbers, nearly a quarter of a million octopuses were found in UK waters this year – that’s a huge increase from historical averages.”

The Mediterranean octopus is native to British seas but ordinarily in such small numbers it is seldom observed. An explosive growth is attributed to a combination of a mild winter and a warm breeding season. These ideal conditions meant increased juvenile survival, potentially supported by large numbers of other marine life also recorded.

An Uncommon Occurrence

The most recent occasion, such an octopus proliferation of this size was observed in 1950, with past documentation indicating the one before that occurred in the turn of the 20th century.

The sheer quantity of octopuses meant they could be easily spotted in shallow waters for the first time in living memory. Video footage show octopuses being sociable – unlike their typical solitary behavior – and “walking” along the ocean floor on their tentacle tips. One individual was even filmed grabbing an underwater camera.

“On my initial dive in that area this year I saw multiple octopuses,” the officer added. “They are sizeable. Two kinds exist in UK waters. The curled octopus is quite small, the size of a ball, but the *Octopus vulgaris* can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

Another mild winter going into 2026 meant it was possible another surge the following year, 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 persist indefinitely,” they said. “But the sea keeps giving us surprises these days so it’s quite an unpredictable situation.”

The report also celebrated further encouraging coastal sightings around the UK coastline, including:

• Highest-ever counts of gray seals observed in one northern region.
• Exceptional populations of puffins on a Welsh island.
• The initial discovery of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A Mediterranean fish species spotted off the coast of Sussex for the first occasion.

Not All Positive News

The year had its low points, however. “The period was framed by environmental disasters,” said a head of marine conservation. “A major tanker collision in March and an accidental discharge of tonnes of plastic biobeads off the southern coast served as stark reminders. Dedicated individuals are putting in immense work to defend and heal our shorelines.”