Record Octopus Bloom in the South West
Warm waters off the south west of England produced the largest octopus bloom in 75 years, according to conservationists. Divers and snorkellers reported multiple sightings of the creatures walking, mating, and even interacting with underwater cameras. Fishers found them in crab and lobster pots and during trawling. Matt Slater, marine conservation officer at Cornwall Wildlife Trust, described the surge as “an exceptional octopus population explosion, the like of which hasn’t been seen in our waters for 75 years.” Despite causing some concern for fishers, local ports quickly developed markets to sell the octopuses globally. The species, which lives only two years but can grow up to 1.5 metres across and weigh six to eight kilograms, may continue to be present next year, though blooms historically last only a couple of years. Slater noted that warming seas could make such events more frequent and expand the octopus’s northern range.
Mixed Year for UK Coastal Wildlife
While octopus numbers soared, other parts of the UK’s coastline faced environmental setbacks. The Wildlife Trusts’ 2025 review highlighted pollution, destructive fishing, and climate-driven heatwaves affecting marine life. In March, a North Sea collision between an oil tanker and a container ship spilled large quantities of plastic resin pellets, and in November, nearly 4.5 tonnes of bio-beads were released from a water treatment plant in Sussex. Clean-up efforts recovered almost 19 tonnes of “nurdles” from Lincolnshire beaches, while bio-beads polluted Camber Sands and Rye Harbour nature reserve, posing threats to wildlife, including 80 species of birds. Sussex Wildlife Trust is actively removing the beads from protected saltmarshes.
Puffin Comebacks and Conservation Successes
There were notable successes as well. The Wildlife Trusts of South and West Wales recorded a record 46,000 puffins on Skomer Island, and the Ulster Wildlife Trust confirmed puffins breeding on the Isle of Muck after removing invasive brown rats. Ruth Williams, head of marine at the Wildlife Trusts, emphasized the resilience of coastal habitats, pointing to mussel beds forming off the Sussex coast in areas previously devastated by bottom trawling.
Climate Change Drives Species Shifts
Rising sea temperatures and milder winters are pushing warmer-water species north. Observers recorded Pacific oysters on Alderney, red ripple bryozoan encrusting habitats, sea slugs arriving from warmer waters, the first volcano barnacles in North Wales, and the dominance of Montagu’s crabs in South Devon and Cornwall. The UK also saw rare sightings of critically endangered angelsharks and sunfish off the east coast, while grey seals reached record numbers at South Walney nature reserve.
Restoration Efforts and Future Outlook
Conservation groups worked to improve ecosystem resilience by restoring seagrass in Essex, Hampshire, and Durham, and returning 300,000 native oysters to the Humber Estuary. The Wildlife Trusts predict that octopus blooms and other climate-indicator species will continue appearing in UK waters, while cod and haddock shift north and anchovies, sardines, and garfish increase in the south west. They are calling for a ban on bottom trawling to protect seafloor habitats, with Ruth Williams urging, “Now the Government needs to ban this horrific practice from all Marine Protected Areas.”
2025 showcased both the astonishing adaptability of species like octopuses and puffins and the ongoing threats from pollution, climate change, and destructive fishing, highlighting the delicate balance of the UK’s coastal and marine ecosystems.
