Sperm whales drop giant poop bombs to save themselves from orca attack

Sperm whales blasted a "big dark bubble" of poop to prevent an impending orca attack off the southern coast of Western Australia.

Scientists witnessed the clever defense strategy unfold Tuesday (March 19) during a tourist excursion in Bremer Canyon, a whale-watching hotspot off the coast between Albany and Hopetoun. They described seeing a "cloud of diarrhea" permeate the water, and this rarely seen defense mechanism seemed to help the sperm whale pod escape what could have been a fatal attack by at least 30 killer whales, ABC News Australia reported. 

"It's called defense defecation," Jennah Tucker, a marine biologist with Oceans Blueprint, a marine and environmental sciences research organization, who was on the charter boat, told ABC. When the animals defecate, she said, they pass their huge tails through their poop to drive away or confuse attackers.

As the event unfolded, onlookers noticed a large, "dark bubble" pop up to the water's surface. At first, they thought it was blood from one of the sperm whales, potentially a small calf. But when the team later reviewed footage of the plume, they realized it was actually whale poop.

"Because [a] sperm whale's diet consists mostly of squid, they actually have this really reddish colored poo," she said.

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In this demonstration of defense defecation, the pod formed a circle with their heads together, and the whales fanned their tails in unison — forcing their excrement toward the unsuspecting orcas.

"This is called a rosette, another defensive mechanism they use when they're under attack," Tucker said.

Tucker told ABC she noticed that the sperm whales looked distressed and exhausted. However, their fecal warfare worked, and the orcas swam off in search of fresher waters. It was in the midst of this mayhem that researchers saw the big, blobby poop bubble rise to the water's surface.

There have been only a few documented instances of orca attacks on sperm whales, largely due to the sheer size differential between the two species.

"Sperm whales are considered an apex predator, and historically, it was thought that they were pretty much immune to killer whale attacks," Tucker said. "It's actually pretty adventurous for orcas to try to take on sperm whales. They're punching above their weight."