The Octopus Invasion?

In 2025, an explosion of common octopus appeared across the southwest coast of England — baffling fishermen and fascinating scientists. What started as an unusual observation by local divers and fishermen quickly became a major ecological event.

Dr. Keith Hiscock, MBA, Associate Fellow at the Marine Biological Association, explains what led to this “octopus bloom”, how it connects to long-term changes in our seas, and what it could mean for the future of UK marine life.

The first signs came in 2023, when divers recorded a female octopus guarding her hatched eggs — clear evidence that octopus were breeding in British waters. Fast forward to 2025, and their numbers have exploded. Fishermen noticed first, as octopus began raiding lobster and crab pots — much to their frustration (and later for some, profit, when exports to Spain and Portugal boomed).

But beyond the headlines, this event raises important scientific questions:

Why now?
Is this linked to climate change and warmer seas?
Or are we seeing part of a natural cycle, similar to octopus “plagues” recorded in 1900, 1920, and 1950?

Dr. Hiscock explains how data from the Southwest Marine Ecosystems Programme, which has tracked regional sea changes for over 15 years, helps scientists piece together this complex puzzle. From shifts in seawater temperature to the biological rhythms of marine species, these records reveal how dynamic — and sometimes unpredictable — our oceans can be.

Lovely clip from @paulnaylormarinephoto Paul Naylor