2025 Proclaimed the 'Year of the Octopus' Along Britain's South Coast.

Exceptionally high sightings of one of the world's most intelligent invertebrates over the summer months have prompted the declaration of 2025 as “the year of the octopus” in a yearly report of UK coastal waters.

A Confluence of Factors for a Population Boom

An unusually warm winter coupled with a remarkably hot spring catalyzed a huge population of *Octopus vulgaris* to settle along England’s south coast, from Penzance in Cornwall to south Devon.

“The scale of the catch was roughly over a dozen times what we would usually anticipate in this region,” commented a marine life specialist. “Based on the totals, approximately 233,000 octopuses were present in these waters this year – that’s a huge increase from the norm.”

The Mediterranean octopus is indigenous to these waters but typically so rare it is infrequently encountered. A sudden increase is caused by the dual effect of gentle winter conditions and favorable spring temperatures. This perfect scenario meant a higher survival rate for young, maybe aided by significant populations of spider crabs also recorded.

A Historic Event

Previously, a population surge of this scale of this size was recorded in the 1950s, with past documentation indicating the one before that was in 1900.

The remarkable abundance of octopuses meant they could be frequently seen in coastal areas for a rare occurrence. Video footage show octopuses being sociable – contrary to their normally lone nature – and moving along the ocean floor on their arm ends. One creature was even seen investigating submarine recording equipment.

“During a first dive off the Lizard peninsula this year I saw five octopuses,” the officer added. “They are large specimens. Two kinds exist in UK waters. The curled octopus is quite small, football-sized, but the *Octopus vulgaris* can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

A second gentle winter going into 2026 meant it was possible a repeat event in 2026, because in the past, in similar situations, events have occurred consecutively for two years in a row.

“But, it's improbable, based on past events, that it will become a permanent fixture,” they said. “But the sea keeps giving us surprises currently so it’s quite an unpredictable situation.”

The assessment also celebrated other “surprises, successes and joyful moments” around the UK coastline, including:

• Unprecedented numbers of grey seals seen in one northern region.
• Peak numbers of puffins on a Welsh island.
• A first-ever sighting of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A variable blenny spotted off the coast of a southern county for the first occasion.

A Note of Caution

Challenges were also present, however. “The calendar year was marked by ecological challenges,” said a head of marine conservation. “A major tanker collision in March and a spill of plastic pollution off the southern coast served as stark reminders. Staff and volunteers are making huge efforts to protect and restore our shorelines.”