2025 Declared The Year for Octopuses Off Britain's Southern Shores.
Unprecedented observations of a supremely intelligent sea creature over the summer months have resulted in the naming of 2025 as “the year of the octopus” in a seasonal assessment of UK coastal waters.
A Confluence of Factors Driving a Surge
A gentle winter coupled with a very warm springtime triggered unprecedented numbers of Mediterranean octopuses to take up residence along the shores from Cornwall to Devon, across the southwestern peninsula.
“The volume of octopuses caught was approximately 13 times what we would typically see in the waters around Cornwall,” commented a marine conservation officer. “Calculating the figures, nearly a quarter of a million octopuses were found in UK waters this year – representing a massive jump from historical averages.”
The common octopus is native to these waters but typically so rare it is rarely seen. A sudden increase is caused by the dual effect of a mild winter and favorable spring temperatures. These ideal conditions meant increased juvenile survival, potentially supported by abundant stocks of spider crabs seen in the area.
A Historic Event
Previously, such an octopus proliferation of this size was documented in the mid-20th century, with past documentation indicating the previous major event occurred in 1900.
The remarkable abundance of octopuses meant they could be readily observed in shallow waters for a rare occurrence. Video footage show octopuses congregating together – unlike their typical solitary behavior – and “walking” along the seabed on their arm ends. A curious octopus was even filmed grabbing an underwater camera.
“On my initial dive in that area this year I saw multiple octopuses,” the specialist continued. “And these are big. There are two types in UK waters. The curled octopus is quite small, about the size of a football, but these common octopuses can be reaching impressive sizes.”
Future Prospects and Other Surprises
A second gentle winter this coming winter could lead to another surge the following year, because based on records, in similar situations, populations have surged again for two consecutive years.
“But, it's improbable, looking at history, that it will go on for a long time,” they said. “Marine life is unpredictable these days so it’s hard to forecast.”
The assessment also noted other “surprises, successes and joyful moments” along the coast, including:
- Unprecedented numbers of gray seals observed in one northern region.
- Peak numbers of puffins on a Welsh island.
- The initial discovery of an unusual mollusc in Yorkshire, usually found in the south-west.
- A type of blenny spotted off the coast of Sussex for the inaugural time.
Environmental Concerns
The year had its low points, however. “The calendar year was marked by marine incidents,” said a head of marine conservation. “A significant shipping incident in March and an accidental discharge of industrial pellets off the southern coast served as stark reminders. Staff and volunteers are working tirelessly to defend and heal our shorelines.”
