First-of-its-kind footage captures the moment an octopus fires projectiles at predatory fish while hiding in a clam shell, like a mini sharpshooter.
The clip, filmed for Netflix's new series "Our Oceans," shows a coconut octopus (Amphioctopus marginatus), also known as a veined octopus, as it fires tiny stones from its siphon — a tube-like structure octopuses use to swim and steer — at fish swimming by.
"We couldn't believe it," Katy Moorhead, assistant producer and field director for the series, told Live Science in an email. "She was shooting fish, with stones, through her siphon! We were so surprised. Nobody had ever recorded veined octopuses using their siphons as weapons before."
The team filmed the clip around 30 feet (9 meters) below the ocean surface in Southeast Asia. The filmmakers were initially looking at the impact of plastic pollution on the ocean, filming a lone octopus living in a trash-filled seabed. But when they reviewed the footage, they realized they'd captured a completely new behavior.
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The team returned to the octopus to find out if this was a one-off event, or if the octopus had worked out how to use its siphon as a pea-shooter to deter predators. Roger Munns, the director of photography, spent 110 hours with the octopus over three weeks, eventually capturing the behavior in detail — showing how she gathered rocks and debris, loaded it, then fired the projectiles out. "She turns her siphon into a gun," former President Barack Obama, who narrates the series, said in the show.
The stones were fired out so fast it could only be seen on the footage in slow motion.
"Faced with a large fish who was giving away the location of her clam hideout, the octopus fired a stone out of its breathing siphon, and hit the fish square on the face," executive producer James Honeyborne told Live Science in an email.
Coconut octopuses tend to live in sandy, muddy habitats in shallow waters. They're found throughout the Indian Ocean and emerge from their hiding places at dawn and dusk to forage. They're known for building armor from clam and coconut shells, pulling the halves together to create shields. When not in use, they carry these shells around with them — stacking them up, sitting inside the shells, then sticking their arms out to move along the seafloor.
The newly recorded shooting behavior is now being analyzed to better understand how and why these octopuses do it. "The fish were clearly startled and did then leave the vicinity of the octopus, suggesting it is an effective deterrent," series producer Jonathan Smith told Live Science in an email. "A scientist is now analyzing this surprising footage to get more answers."
"Our Oceans" is available to stream on Netflix.
