2025 Hailed as The Year for Octopuses Off Britain's Southern Shores.

Unprecedented observations of one of the world's most intelligent invertebrates this past summer have led to the declaration of 2025 as the year for octopuses in a yearly report of UK coastal waters.

A Confluence of Factors for a Population Boom

A mild winter followed by a very warm springtime catalyzed a massive influx of common octopuses (*Octopus vulgaris*) to take up residence along England’s south coast, from Penzance in Cornwall to south Devon.

“The volume of octopuses caught was approximately 13 times what we would typically see in the waters around Cornwall,” commented a marine conservation officer. “When we added up the numbers, approximately 233,000 octopuses were found in these waters this year – which is a significant rise from historical averages.”

The Mediterranean octopus is native to British seas but typically so rare it is rarely seen. A sudden increase is the result of the dual effect of a mild winter and a warm breeding season. These ideal conditions meant increased juvenile survival, maybe aided by large numbers of other marine life also recorded.

An Uncommon Occurrence

The last time, an octopus bloom of this size was observed in 1950, with archival data indicating the last bloom prior to that happened in 1900.

The huge numbers of octopuses meant they could be easily spotted in nearshore environments for the first time in living memory. Underwater recordings show octopuses being sociable – unlike their typical solitary behavior – and “walking” along the ocean floor on their tentacle tips. A curious octopus was even recorded reaching for an underwater camera.

“During a first dive off the Lizard peninsula this year I saw multiple octopuses,” the specialist continued. “They are sizeable. There are two types in UK waters. The curled octopus is rather small, the size of a ball, but these newcomers can be reaching impressive sizes.”

Predictions and Marine Joy

Another mild winter going into 2026 meant it was possible a repeat event next year, because in the past, in similar situations, the blooms have repeated for two years in a row.

“Still, the chances are low, looking at history, that it will become a permanent fixture,” they said. “The ocean is full of surprises currently so it’s a very uncertain scenario.”

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

• A record number of gray seals recorded in Cumbria.
• Exceptional populations of the iconic seabirds on Skomer.
• The first recording of an unusual mollusc in a northern county, typically a southwestern species.
• A type of blenny spotted off the coast of Sussex for the first occasion.

Not All Positive News

Not everything was good news, however. “The year was bookended by environmental disasters,” stated an expert. “A major tanker collision in the North Sea and a spill of plastic pollution off the Sussex coast highlighted ongoing threats. Staff and volunteers are making huge efforts to protect and restore our coasts.”