Octopus caught hitching a ride on a dolphin

The extraordinary sight was captured off Berry Head, Devon, England by Risso's Dolphin Project South West volunteer Bill Coulson.

The Marine Biological Association said the remarkable images of a Risso's dolphin appearing to be "ridden" by an octopus provide "striking evidence of how an ongoing bloom in octopus numbers may be affecting marine wildlife in the sea off the Devon and Cornwall coast."

The incredible sighting of a marine animal generally considered a deep-water, offshore species comes as scientists continue to investigate unusually high numbers of octopus being recorded around the Southwest coastline.

The observation links two major areas of current marine research that are revealing changes in marine ecosystems as seas warm: the Marine Biological Association's work examining the increase in the abundance of common octopus, which began in 2025, and research led by University of Exeter MSc researcher Josh Symes, who is studying Risso's dolphins across the region using photo ID.

Risso's dolphins are among the U.K.'s least understood cetaceans and are known to feed primarily on squid and other cephalopods. However, the recent abundance of octopus may be creating new feeding opportunities for these distinctive dolphins.

Josh Symes said: "These photographs offer a fascinating glimpse into the feeding ecology of Risso's dolphins and the changing marine environment around our coasts.

"Risso's dolphins are closely associated with cephalopods, and sightings like this help us understand how they are responding to changing prey availability.

"The images also highlight the value of citizen science, as observations from volunteers are helping us build a clearer picture of marine wildlife across the Southwest."

Bryce Stewart, senior research fellow at the Marine Biological Association, said: "We're still seeing lots of reports of octopus across Southwest waters, and understanding what's driving these changes is an important area of research.

"Observations of interactions between Risso's dolphins and common octopus help to demonstrate how shifts in the abundance of a species can ripple through the wider ecosystem.

"It's a powerful reminder of how interconnected our marine environment is and why we need to continue studying it."