2025 Declared The Year for Octopuses Off Britain's Southern Shores.
Exceptionally high sightings of a supremely intelligent sea creature during the summer season have led to the designation of 2025 as the octopus's year in an annual review of UK coastal waters.
A Perfect Storm Driving a Surge
An unusually warm winter coupled with a remarkably hot spring catalyzed a massive influx of Mediterranean octopuses to settle along England’s south coast, from Penzance in Cornwall to south Devon.
“The volume of octopuses caught was approximately over a dozen times what we would typically see in Cornish waters,” explained a marine life specialist. “Based on the totals, around 233 thousand octopuses were present in UK waters this year – that’s a huge increase from what is typical.”
The Mediterranean octopus is indigenous to these waters but typically so rare it is rarely seen. An explosive growth is attributed to a combination of a mild winter and a warm breeding season. This perfect scenario meant more larvae, possibly in part fuelled by abundant stocks of a favored prey species noted in recent years.
A Rare Phenomenon
The most recent occasion, such an octopus proliferation this significant was documented in the mid-20th century, with historical records indicating the last bloom prior to that happened in 1900.
The huge numbers of octopuses meant they could be frequently seen in nearshore environments for the first time in living memory. Video footage show octopuses being sociable – contrary to their normally lone nature – and moving along the ocean floor on their arm ends. One individual was even filmed grabbing submarine recording equipment.
“On my initial dive off the Lizard peninsula this year I saw five octopuses,” the officer added. “They are sizeable. We have two species in UK waters. One species is quite small, the size of a ball, but these newcomers can be with a span of 1.5 meters.”
Looking Ahead & Coastal Highlights
A second gentle winter heading into next year suggests the potential a second bloom next year, because historically, under these conditions, populations have surged again for two years running.
“Still, the chances are low, from previous blooms, that it will go on for a long time,” they said. “But the sea keeps giving us surprises currently so it’s a very uncertain scenario.”
The assessment also noted other “surprises, successes and joyful moments” around the UK coastline, including:
- Highest-ever counts of gray seals observed in Cumbria.
- Record numbers of the iconic seabirds on a Welsh island.
- The first recording of an unusual mollusc in a northern county, normally residing farther south.
- A variable blenny found off the coast of Sussex for the inaugural time.
Environmental Concerns
Challenges were also present, however. “The calendar year was marked by marine incidents,” said a head of marine conservation. “A significant shipping incident in the North Sea and a spill of plastic pollution off the southern coast highlighted ongoing threats. Staff and volunteers are putting in immense work to safeguard and rehabilitate our coasts.”
