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

Unprecedented encounters of a remarkably clever cephalopod 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 Driving a Surge

A gentle winter coupled with a remarkably hot spring catalyzed unprecedented numbers of Mediterranean octopuses to establish themselves along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.

“The volume of octopuses caught was of the order of about over a dozen times what we would typically see in this region,” commented a marine conservation officer. “Calculating the figures, approximately 233,000 octopuses were caught in British seas this year – that’s a huge increase from what is typical.”

*Octopus vulgaris* is found in UK waters but typically so rare it is infrequently encountered. A sudden increase is attributed to the dual effect of gentle winter conditions and favorable spring temperatures. This perfect scenario meant a higher survival rate for young, potentially supported by significant populations of spider crabs seen in the area.

An Uncommon Occurrence

Previously, such an octopus proliferation of this size was observed in the mid-20th century, with past documentation indicating the last bloom prior to that was in the turn of the 20th century.

The remarkable abundance of octopuses meant they could be frequently seen in coastal areas for the first time in living memory. Underwater recordings show octopuses congregating together – they are usually solitary – and “walking” along the seabed on their arm ends. One individual was even seen investigating an underwater camera.

“The first time I dived there this year I saw five of these creatures,” they noted. “They are sizeable. Two kinds exist in these waters. The curled octopus is rather small, football-sized, but these newcomers can be reaching impressive sizes.”

Future Prospects and Other Surprises

If conditions remain mild going into 2026 meant it was possible a repeat event in 2026, because in the past, with such patterns, populations have surged again for two years in a row.

“However, it is unlikely, from previous blooms, that it will become a permanent fixture,” they cautioned. “But the sea keeps giving us surprises these days so it’s quite an unpredictable situation.”

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

• A record number of gray seals seen in Cumbria.
• Exceptional populations of puffins on a Welsh island.
• A first-ever sighting of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A type of blenny discovered off the coast of Sussex for the first time.

Environmental Concerns

The year had its low points, however. “The year was bookended by environmental disasters,” stated an expert. “A significant shipping incident in March and a spill of industrial pellets off the southern coast were serious issues. Staff and volunteers are putting in immense work to defend and heal our coasts.”