The year 2025 has been designated as "the Year of the Blooming Octopus" by a wildlife charity, following a significant increase in octopus sightings off the south-west coast of England, with record numbers observed.

According to the Wildlife Trusts' annual marine review, the summer of 2025 saw the highest octopus numbers since 1950, marking a notable surge in their population.

Climate change, specifically warmer winters, is believed to be a contributing factor to the sudden growth in octopus numbers, a phenomenon referred to as a "bloom".

Official statistics support the charity's findings, revealing that UK fishermen caught over 1,200 tonnes of octopus in the summer of 2025, a substantial catch.

This represents a significant increase from previous years, with only one year since 2021 seeing a catch of over 200 tonnes of octopus.

The majority of the octopuses spotted are of the species Octopus vulgaris, commonly found in the Mediterranean Sea, with volunteers from the Wildlife Trusts in Cornwall and Devon reporting a 1,500 percent increase in sightings along a stretch of the south coast compared to 2023.

Matt Slater from the Cornwall Wildlife Trust described the experience, saying, "It's been remarkable, with octopuses using jet propulsion, camouflage, and even walking on two legs to move away from divers underwater."

Observations have also included octopuses cleaning themselves, showcasing their unique behavior.

It remains to be seen whether the rise in octopus numbers is a long-term trend or a cyclical event that will return to normal levels after this year's bloom.

As octopuses primarily feed on shellfish such as lobsters, crabs, and scallops, the Wildlife Trusts warn that sustained high population numbers may necessitate changes in fishing and eating habits.

Ruth Williams, head of marine for The Wildlife Trusts, noted that the increase in octopus numbers is having an impact on shellfish species and, by extension, the fishing industry that targets them.

However, Williams also highlighted the potential for the fishing industry to adapt to these changes, with ongoing research into evolving fisheries in response to climate change.

Government data indicates a decline in crab landings, while catches of lobster, crawfish, and scallops have remained stable.

While the news about octopus populations is positive, the Wildlife Trusts' marine review also contains more concerning information.

The year was marked by environmental disasters, including a collision between an oil tanker and a container ship in the North Sea in March, resulting in a significant spill of plastic resin pellets, and the release of nearly 4.5 tonnes of bio-beads from a water treatment plant in Sussex in November.

There was some better news for wildlife elsewhere, with a record 46,000 puffins recorded on Skomer, Pembrokeshire, while the charismatic black and white bird has made a comeback on the Isle of Muck following conservation efforts by Ulster Wildlife Trust to remove invasive brown rats.