2025 Declared The Year for Octopuses Off England's South Coast.

Unprecedented sightings of one of the world's most intelligent invertebrates over the summer months have led to the declaration of 2025 as the year for octopuses in an annual review of the nation's marine environment.

A Confluence of Factors Driving a Surge

A mild winter and then an exceptionally warm spring prompted a huge population of common octopuses (*Octopus vulgaris*) to take up residence along England’s south coast, from Penzance in Cornwall to south Devon.

“The volume of octopuses caught was roughly thirteen times what we would normally expect in this region,” stated an ocean conservation expert. “When we added up the numbers, around 233 thousand octopuses were found in UK waters this year – which is a significant rise from the norm.”

*Octopus vulgaris* is native to these waters but usually so scarce it is infrequently encountered. An explosive growth is caused by a combination of a mild winter and a warm breeding season. This perfect scenario meant more larvae, maybe aided by abundant stocks of spider crabs seen in the area.

An Uncommon Occurrence

Previously, an octopus bloom of this size was recorded in the mid-20th century, with past documentation indicating the one before that happened in 1900.

The huge numbers of octopuses meant they could be readily observed in nearshore environments for the first time in living memory. Underwater recordings show octopuses being sociable – contrary to their normally lone nature – and moving along the ocean floor on their tentacle tips. One creature was even recorded reaching for a diver's camera.

“On my initial dive in that area this year I saw five of these creatures,” they noted. “They are sizeable. There are two types in these waters. The curled octopus is smaller, the size of a ball, but the *Octopus vulgaris* can be with a span of 1.5 meters.”

Looking Ahead & Coastal Highlights

If conditions remain mild this coming winter could lead to a repeat event next year, because based on records, in similar situations, populations have surged again for two years running.

“But, it's improbable, looking at history, that it will persist indefinitely,” they said. “The ocean is full of surprises at the moment so it’s quite an unpredictable situation.”

The annual review also celebrated other “surprises, successes and joyful moments” around the UK coastline, including:

• Unprecedented numbers of gray seals observed in Cumbria.
• Peak numbers of puffins on an island off Wales.
• The initial discovery of an unusual mollusc in a northern county, normally residing farther south.
• A Mediterranean fish species found off the coast of a southern county for the first time.

A Note of Caution

Not everything was good news, however. “The year was bookended by ecological challenges,” said a head of marine conservation. “A major tanker collision in the North Sea and an accidental discharge of tonnes of plastic biobeads off the southern coast highlighted ongoing threats. Conservation teams are working tirelessly to safeguard and rehabilitate our shorelines.”