2025 Hailed as 'The Octopus Year' Off England's South Coast.
Record-breaking observations of a supremely intelligent sea creature during the summer season have prompted the declaration of 2025 as the octopus's year in a yearly report of UK coastal waters.
A Confluence of Factors for a Population Boom
A mild winter and then a very warm springtime prompted unprecedented numbers of common octopuses (*Octopus vulgaris*) to establish themselves along the shores from Cornwall to Devon, from Penzance in Cornwall to south Devon.
“The volume of octopuses caught was roughly thirteen times what we would usually anticipate in this region,” stated a marine life specialist. “When we added up the numbers, around 233 thousand octopuses were found in British seas this year – that’s a huge increase from the norm.”
*Octopus vulgaris* is indigenous to UK waters but usually so scarce it is seldom observed. An explosive growth is attributed to the dual effect of gentle winter conditions and favorable spring temperatures. This perfect scenario meant increased juvenile survival, potentially supported by large numbers of spider crabs noted in recent years.
A Rare Phenomenon
The last time, an octopus bloom of this size was documented in the 1950s, with past documentation indicating the previous major event happened in 1900.
The sheer quantity of octopuses meant they could be easily spotted in nearshore environments for a rare occurrence. Underwater recordings show octopuses being sociable – unlike their typical solitary behavior – and moving along the bottom on their arm ends. A curious octopus was even recorded reaching for submarine recording equipment.
“On my initial dive off the Lizard peninsula this year I saw five octopuses,” they noted. “And these are big. There are two types in UK waters. One species is smaller, the size of a ball, but these common octopuses can be up to a metre and a half wide.”
Looking Ahead & Coastal Highlights
Another mild winter this coming winter could lead to a repeat event next year, because in the past, under these conditions, events have occurred consecutively for two years running.
“However, it is unlikely, looking at history, that it will persist indefinitely,” they cautioned. “The ocean is full of surprises currently so it’s quite an unpredictable situation.”
The report also highlighted other “surprises, successes and joyful moments” along the coast, including:
- A record number of grey seals observed in one northern region.
- Exceptional populations of puffins on Skomer.
- A first-ever sighting of the *Capellinia fustifera* nudibranch in Yorkshire, usually found in the south-west.
- A variable blenny found off the coast of Sussex for the first occasion.
Not All Positive News
Challenges were also present, however. “The year was bookended by ecological challenges,” stated an expert. “A major tanker collision in the North Sea and a spill of plastic pollution off the Sussex coast were serious issues. Staff and volunteers are making huge efforts to safeguard and rehabilitate our marine habitats.”