2025 Proclaimed The Year for Octopuses Along England's South Coast.

Record-breaking encounters of one of the world's most intelligent invertebrates during the summer season have led to the naming of 2025 as the octopus's year in an annual review of Britain’s seas.

A Perfect Storm Leading to an Explosion

A mild winter coupled with a remarkably hot spring catalyzed a huge population of Mediterranean octopuses to take up residence along the southern coastline of England, across the southwestern peninsula.

“The volume of octopuses caught was approximately over a dozen times what we would normally expect in Cornish waters,” explained a marine life specialist. “Based on the totals, nearly a quarter of a million octopuses were caught in UK waters this year – that’s a huge increase from historical averages.”

The common octopus is native to these waters but usually so scarce it is seldom observed. An explosive growth is caused by a combination of a mild winter and a warm breeding season. Such favorable circumstances meant a higher survival rate for young, maybe aided by significant populations of spider crabs also recorded.

A Rare Phenomenon

The last time, a population surge of this scale of this size was recorded in the 1950s, with archival data indicating the previous major event was in the turn of the 20th century.

The sheer quantity of octopuses meant they could be readily observed in nearshore environments for the first time in living memory. Diver videos show octopuses gathering in groups – contrary to their normally lone nature – and moving along the bottom on their tentacle tips. A curious octopus was even filmed grabbing a diver's camera.

“The first time I dived off the Lizard peninsula this year I saw multiple octopuses,” they noted. “They are sizeable. There are two types in these waters. One species is quite small, the size of a ball, but these common octopuses can be reaching impressive sizes.”

Future Prospects and Other Surprises

Another mild winter going into 2026 suggests the potential a repeat event in 2026, because in the past, in similar situations, events have occurred consecutively for two years running.

“But, it's improbable, from previous blooms, that it will become a permanent fixture,” they said. “Marine life is unpredictable currently so it’s quite an unpredictable situation.”

The report also celebrated further encouraging coastal sightings along the coast, including:

• A record number of grey seals seen in one northern region.
• Exceptional populations of puffins on Skomer.
• The first recording of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
• A Mediterranean fish species discovered off the coast of Sussex for the inaugural time.

A Note of Caution

The year had its low points, however. “The year was bookended by marine incidents,” noted a conservation leader. “A significant shipping incident in March and a spill of industrial pellets off the Sussex coast highlighted ongoing threats. Staff and volunteers are putting in immense work to safeguard and rehabilitate our marine habitats.”