2025 Declared 'The Octopus Year' Off England's South Coast.
Record-breaking encounters of one of the world's most intelligent invertebrates this past summer have resulted in the declaration of 2025 as the year for octopuses in a yearly report of the nation's marine environment.
A Confluence of Factors Leading to an Explosion
A gentle winter followed by a very warm springtime triggered a massive influx of Mediterranean octopuses to settle along the shores from Cornwall to Devon, spanning the Cornish and Devonian coasts.
“The scale of the catch was approximately 13 times what we would usually anticipate in Cornish waters,” commented an ocean conservation expert. “Calculating the figures, nearly a quarter of a million octopuses were found in British seas this year – representing a massive jump from what is typical.”
*Octopus vulgaris* 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 abundant stocks of spider crabs noted in recent years.
A Rare Phenomenon
The most recent occasion, an octopus bloom this significant was documented in the mid-20th century, with past documentation 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. Video footage show octopuses being sociable – they are usually solitary – and ambulating along the seabed on their tentacle tips. A curious octopus was even filmed grabbing a diver's camera.
“On my initial dive off the Lizard peninsula this year I saw multiple octopuses,” they noted. “And these are big. There are two types in UK waters. One species is quite small, football-sized, but the *Octopus vulgaris* can be up to a metre and a half wide.”
Predictions and Marine Joy
If conditions remain mild this coming winter suggests the potential a second bloom in 2026, because in the past, in similar situations, the blooms have repeated 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 at the moment so it’s hard to forecast.”
The annual review also highlighted other “surprises, successes and joyful moments” around the UK coastline, including:
- Unprecedented numbers of gray seals recorded in one northern region.
- Record numbers of puffins on an island off Wales.
- The initial discovery of a rare sea slug in a northern county, usually found in the south-west.
- A type of blenny spotted off the coast of a southern county for the inaugural time.
A Note of Caution
The year had its low points, however. “The period was framed by marine incidents,” noted a conservation leader. “A major tanker collision in March and a spill of plastic pollution off the Sussex coast were serious issues. Conservation teams are working tirelessly to defend and heal our shorelines.”