The power of eight

In 2025, UK waters were invaded by hordes of common octopus. Could such 'blooms' become more regular and what might be the impact?

- Kevin Parr profiles this remarkable cephalopod

For a couple of years, Inky the octopus was a popular attraction at the National Aquarium of New Zealand in Napier. Then, one morning in 2016, his tank was empty. Inky had made a daring break for freedom.

Aquarium staff soon discovered that a small gap had been left at the top of the tank following maintenance work. Inky, it seems, had squeezed through, slithered across the floor and then slipped into a drainage pipe that led to the sea. His daring escape inspired worldwide media interest and several children’s books.

Inky’s exploits were not out of the ordinary, though. Members of the order Octopoda are renowned for their problem-solving abilities and contortion acts, navigating mazes, opening jars and squeezing through the most unlikely of gaps. At a marine educational centre in New Zealand’s capital, Wellington, an octopus was caught sneaking into another tank at night to pinch crabs - a cunning ploy of which fishers in southwest England are only too aware.

Permit conditions issued by the Devon and Severn Inshore Fisheries and Conservation Authority state that pots used for crab and lobster fishing must be installed with a gap at least 84mm wide and 46mm high to allow undersized or immature shellfish to escape. That edict has lately created a problem.

In early 2025, fishers began finding an increasing number of pots either empty or containing the remains of predated crustaceans. On one occasion, a suspected culprit was also discovered inside: a common octopus (Octopus vulgaris) that, it seems, had squeezed through that gap - barely larger than a credit card - then, having overindulged in crab and lobster, was too portly to get back out.

A BUMPER YEAR