Home / Environment / Octopus Invasion: UK Waters See Historic Population Boom
Octopus Invasion: UK Waters See Historic Population Boom
28 Jan
Summary
- Octopus population surged significantly in UK waters during 2025.
- Warmer sea temperatures caused migration from southern Europe.
- Fishing industry reports a 30-50% drop in crab, lobster, and scallop catches.
British waters experienced a major population bloom of the common octopus in 2025, researchers have confirmed. This surge, comparable to rare historical blooms in 1899-1900, 1932-33, and 1950-51, saw commercial fishery landings increase nearly 65 times higher than recent averages.
Warmer sea temperatures, reaching up to 4C above normal, along with lower saltiness and sustained easterly winds, are cited as key factors. These conditions enabled octopus larvae to migrate from regions like northern France and the Channel Islands, leading scientists to believe the common octopus may now be a resident species in UK waters.
However, the octopus bloom presents a crisis for the fishing industry. Approximately two-thirds of surveyed fishermen reported negative impacts, particularly those targeting brown crabs, European lobsters, and king scallops. Catch rates for these species have fallen by 30% to 50%, leading some fishers to consider changing their target species or leaving the industry.
The Department for Environment, Food and Rural Affairs (Defra) acknowledged the study's importance and stated it is working with the industry to ensure sustainable fishing practices. Defra is also investing in a new Fishing and Coastal Growth Fund to support the sector's future.
