‘Year of the octopus’: How climate change is pushing the sea’s smartest creature into new territory

An “exceptional” number of Mediterranean Octopus have been spotted along the south coast of England this year, putting on rarely-seen displays in shallow waters.

Revered as one of the most intelligent sea creatures, the elusive cephalopod (also known as the Common Octopus) is usually found further south in the warmer waters of the Mediterranean. They have been recorded in large numbers, often referred to as a bloom, in the UK before, but this year’s surge was the biggest since 1950.

Volunteers recorded a staggering 1,500 per cent increase in numbers from the “mini bloom” in 2023, and managed to get rare footage of the creatures ‘walking’, cleaning themselves and mating. One was even filmed grabbing at an underwater camera.

The influx led to conservation charity The Wildlife Trusts declaring 2025 ‘the Year of the Blooming Octopus’. But, is it really a phenomenon worth celebrating?

Why are octopuses moving to UK waters?

Ruth Williams, head of marine conservation at The Wildlife Trusts, says the “population explosion” is likely due to a combination of different environmental factors aligning, including warming waters.

“Sea temperatures are 1.5 to 3℃ higher than usual in the Southwest and warmer winters allow the octopus eggs to survive at higher rates,” she tells Euronews Green.

“However, more research is needed to understand the bloom in more detail.”

The temperature of seas and oceans is rising at an accelerating rate, as they continue to absorb excess heat from human-produced greenhouse gases.

A 2025 study, published in the journalEnvironmental Research Letters, warned that the surface of the ocean is warming four times faster than it was 40 years ago, while average sea surface temperatures have hit an all-time high.

“If the oceans were a bathtub of water, then in the 1980s, the hot tap was running slowly, warming up the water by just a fraction of a degree each decade,” says lead author Professor Chris Merchant.

“But now, the hot tap is running much faster and the warming has picked up speed. The way to slow down that warming is to start closing off the hot tap, by cutting global carbon emissions and moving towards net-zero.”

How does the octopus bloom impact the UK?

While the blooms are classed as a natural occurrence, this year’s record-breaking numbers caused trouble for the shellfish industry - with some workers claiming their catch had plummeted by at least 60 per cent during the summer months.

“Octopuses are predators and feed on lobster, crab and scallops, which are also caught by fishers,” explains Williams.

“If the number of octopus continues to increase then fishers will have to adapt and change their fishery accordingly and there is work underway to look into possible options.”

However, Williams adds that the spike in octopus numbers may be “short-lived” and numbers could return to more normal levels in future years.

A ‘welfare issue’: Is it legal to fish octopus in the UK?

The decrease in shellfish has heightened the demand for more restaurants to start offering octopus on their menu - and helps fishermen maintain their profits.

This summer, more than 1,200 tonnes of octopus were caught by fishermen in UK waters.

This is a significant increase on previous years, but won’t be well-received by animal-rights activists who have long called for octopus to be protected from being killed for human consumption.

In 2021, the UK government amended its Animal Welfare Bill to recognise octopuses as sentient beings, acknowledging that they can feel pain. This prohibits practices such as boiling them alive but does not go as far as stopping them from being killed.

“These are highly intellectual animals so there is a welfare issue, as with many animals caught or farmed for food production,” Williams adds.