Record invasion of octopuses in Great Britain: ecologists declare 2025 their year.

According to ТСН: The Wildlife Trusts organization has declared 2025 the 'year of the octopus' due to a significant increase in the number of these intelligent invertebrates, which has been recorded off the southern coast of England.

The reasons for this phenomenon are associated with the mild winter and warm spring, which contributed to the massive breeding of the Mediterranean octopus. As a result, many animals have settled along the coast of England, from Penzance to south Devon.

Unusual population growth

According to Matt Slater from Cornwall Wildlife Trust, the catch volumes recorded by fishermen are fourteen times higher than the usual figures for Cornwall waters. Experts note that this year, about 233 thousand octopuses have been caught in British waters, which is a significant increase compared to previous years.

Although the common Mediterranean octopus (Octopus vulgaris) was previously found in British waters, its number was insignificant. The current population growth is related not only to the increase in temperature but also to the presence of spider crabs, which are also breeding in this region.

Observations and results

According to the Marine Biological Association, similar mass gatherings of octopuses were last observed in 1950, and before that in the early 20th century.

Thanks to the increase in the number of octopuses, it has become easier to notice them in shallows. Divers have recorded moments when animals gather in groups, which is atypical for them, as octopuses usually lead a solitary lifestyle. One of the octopuses even attempted to grab an underwater camera.

“During my first dive near the Lizard Peninsula, I immediately saw five octopuses. And they are really big,” Slater noted.

He also added that common octopuses in British waters can grow up to one and a half meters wide.

Possible recurrence of the phenomenon

Ecologists do not rule out that under similar mild winters, a 'blooming' of the population may occur again in 2026. However, they emphasize that based on historical data, such phenomena are usually short-lived.

Additionally, the Wildlife Trusts have reported other records for 2025, including a significant number of gray seals in Cumbria and the largest recorded number of puffins on Skokholm Island off the coast of Wales. Volunteers have also discovered some marine animal species in new regions, indicating changes in the ecosystems of British seas.

It was also noted that octopuses can function even during a temporary halt of their heart, and biologists explained this phenomenon.