2025 Proclaimed the 'Year of the Octopus' Along England's South Coast.
Unprecedented observations of a supremely intelligent sea creature over the summer months have prompted the declaration of 2025 as the year for octopuses in a yearly report of Britain’s seas.
A Confluence of Factors for a Population Boom
A mild winter followed by an exceptionally warm spring prompted a huge population of Mediterranean octopuses to take up residence along England’s south coast, across the southwestern peninsula.
“The volume of octopuses caught was of the order of about 13 times what we would usually anticipate in the waters around Cornwall,” commented a marine life specialist. “Based on the totals, around 233 thousand octopuses were found in these waters this year – representing a massive jump from the norm.”
*Octopus vulgaris* is found in UK waters but typically so rare it is infrequently encountered. A population bloom is the result of the dual effect of a mild winter and a warm breeding season. This perfect scenario meant increased juvenile survival, potentially supported by large numbers of spider crabs noted in recent years.
A Historic Event
Previously, a population surge of this scale of this size was observed in the mid-20th century, with past documentation indicating the previous major event was in the turn of the 20th century.
The remarkable abundance of octopuses meant they could be readily observed in nearshore environments for the first time in living memory. Diver videos show octopuses being sociable – unlike their typical solitary behavior – and ambulating along the ocean floor on their arm ends. One individual was even seen investigating an underwater camera.
“During a first dive in that area this year I saw multiple octopuses,” they noted. “And these are big. There are two types in the region. The curled octopus is quite small, about the size of a football, but the *Octopus vulgaris* can be up to a metre and a half wide.”
Predictions and Marine Joy
Another mild winter heading into next year suggests the potential a second bloom in 2026, because in the past, under these conditions, the blooms have repeated for two years in a row.
“However, it is unlikely, looking at history, that it will become a permanent fixture,” they stated. “Marine life is unpredictable these days so it’s a very uncertain scenario.”
The annual review also highlighted additional positive marine news around the UK coastline, including:
- A record number of gray seals recorded in one northern region.
- Peak numbers of the iconic seabirds on Skomer.
- The first recording of a rare sea slug in a northern county, normally residing farther south.
- A Mediterranean fish species spotted off the coast of a southern county for the inaugural time.
A Note of Caution
The year had its low points, however. “The year was bookended by environmental disasters,” stated an expert. “A significant shipping incident in the North Sea and the release of tonnes of plastic biobeads off the Sussex coast served as stark reminders. Staff and volunteers are making huge efforts to protect and restore our shorelines.”
