Over 700 tonnes were landed in Brixham, a big fishing port on the coast, in the first seven months of 2026 alone, more than six times the annual average between 2021 and 2024. In Brixham’s fish market, burly men in yellow overalls haul around big white boxes. Each crate contains a different offering; some crab perhaps or hake. Yet one infamous species is absent. The number of octopuses off England’s south coast has ballooned in the past two years (see chart). But this catch is sequestered in black boxes in its own special room.
The octopus bloom is the most prominent example of how climate change is shifting which creatures choose to reside in British waters. The oceans are warming up. This has meant that species that used to reside in hotter places are finding it easier to survive farther north. But when winds blew their young across the English Channel, they thrived in the newly warm waters. The heat has helped to lure back bluefin tuna, which were once abundant off the British coast before overfishing drove them away. However, like many land-lubbing Britons, some long-term aquatic residents are finding it hard to withstand the heat. As seas have warmed, these species have retreated north.
The mean sea-surface temperature around England today is about about 2.2°C warmer than average conditions over the previous 40 years.
Bryce Stewart of the Marine Biology Association says this is particularly true off the south coast, a boundary area where cooler-water species such as cod and haddock are pushing up against the limits of what they adapted to.
Octopuses were historically more commonly found farther south.
