2025 Declared The Year for Octopuses Along Britain's South Coast.

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

A Perfect Storm for a Population Boom

A gentle winter coupled with an exceptionally warm spring triggered unprecedented numbers of common octopuses (*Octopus vulgaris*) to settle along the southern coastline of England, spanning the Cornish and Devonian coasts.

“The scale of the catch was roughly over a dozen times what we would typically see in the waters around Cornwall,” commented a marine conservation officer. “Calculating the figures, around 233 thousand octopuses were found in these waters this year – representing a massive jump from the norm.”

The Mediterranean octopus is found in these waters but usually so scarce it is rarely seen. A sudden increase is the result of the dual effect of gentle winter conditions and favorable spring temperatures. This perfect scenario meant increased juvenile survival, possibly in part fuelled by large numbers of a favored prey species noted in recent years.

A Rare Phenomenon

Previously, such an octopus proliferation of this size was documented in the 1950s, with past documentation indicating the one before that happened 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. Video footage show octopuses gathering in groups – they are usually solitary – and “walking” along the ocean floor on their tentacle tips. One individual was even recorded reaching for a diver's camera.

“On my initial dive off the Lizard peninsula this year I saw five of these creatures,” they noted. “And these are big. We have two species in UK waters. One species is smaller, football-sized, but these common octopuses can be reaching impressive sizes.”

Looking Ahead & Coastal Highlights

If conditions remain mild 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, from previous blooms, that it will go on for a long time,” they stated. “Marine life is unpredictable at the moment so it’s hard to forecast.”

The annual review also celebrated other “surprises, successes and joyful moments” along the coast, including:

• Highest-ever counts of gray seals observed in Cumbria.
• Exceptional populations of the iconic seabirds on an island off Wales.
• The initial discovery of a rare sea slug in Yorkshire, usually found in the south-west.
• 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 marine incidents,” stated an expert. “A major tanker collision in the North Sea and an accidental discharge of plastic pollution off the Sussex coast highlighted ongoing threats. Dedicated individuals are working tirelessly to defend and heal our shorelines.”