2025 Hailed as the 'Year of the Octopus' Off England's Southern Shores.

Record-breaking sightings of one of the world's most intelligent invertebrates this past summer have prompted the designation of 2025 as the octopus's year in an annual review of Britain’s seas.

Ideal Conditions Leading to an Explosion

A gentle winter followed by a remarkably hot spring prompted a massive influx of *Octopus vulgaris* to establish themselves along the southern coastline of England, spanning the Cornish and Devonian coasts.

“The reported landings was approximately over a dozen times what we would normally expect in Cornish waters,” explained a marine conservation officer. “When we added up the numbers, approximately 233,000 octopuses were found in British seas this year – representing a massive jump from historical averages.”

The common octopus is indigenous to British seas but ordinarily in such small numbers it is infrequently encountered. A population bloom is the result of a combination of gentle winter conditions and favorable spring temperatures. Such favorable circumstances meant a higher survival rate for young, potentially supported by large numbers of spider crabs also recorded.

A Historic Event

The most recent occasion, an octopus bloom of this size was recorded in the 1950s, with historical records indicating the previous major event 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. Diver videos show octopuses gathering in groups – unlike their typical solitary behavior – and “walking” along the seabed on their arm ends. One individual was even seen investigating an underwater camera.

“During a first dive in that area this year I saw five octopuses,” they noted. “They are large specimens. There are two types in these waters. One species is smaller, football-sized, but the *Octopus vulgaris* can be reaching impressive sizes.”

Future Prospects and Other Surprises

If conditions remain mild heading into next year meant it was possible a repeat event in 2026, because in the past, under these conditions, the blooms have repeated for two consecutive years.

“However, it is unlikely, looking at history, that it will go on for a long time,” they stated. “But the sea keeps giving us surprises currently so it’s quite an unpredictable situation.”

The annual review also highlighted additional positive marine news across British shores, including:

• Unprecedented numbers of gray seals recorded in Cumbria.
• Peak numbers of puffins on Skomer.
• The first recording of the *Capellinia fustifera* nudibranch in a northern county, usually found in the south-west.
• A Mediterranean fish species found off the coast of a southern county for the first occasion.

Not All Positive News

The year had its low points, however. “The period was framed by marine incidents,” stated an expert. “A major tanker collision in the North Sea and the release of plastic pollution off the southern coast were serious issues. Dedicated individuals are putting in immense work to defend and heal our shorelines.”