Sperm whales are the seventh largest animals in the world and are considered apex predators. The greatest dangers to these toothed whales are usually man-made, such as fishing nets, boat strikes, and oil spills. Orcas, however, have been known to punch against their weight and will sometimes attack sperm whales.
A tour boat off the coast of Western Australia witnessed this rare event and saw something even more unusual. The sperm whales had formed a circle with their tail flukes pointing outward, a defensive position known as a rosette.
From ABC News Australia:
Then a massive dark bubble rose to the surface. It was initially thought to be a blood bubble from an attack.
"And everything kind of went quiet and there was very solemn sort of mood on the deck of the boat because we thought they'd potentially taken out a calf, as one of the sperm whales did look significantly smaller than the others," Ms Tucker said.
"But then the killer whales all just moved off really suddenly".
When scientists reviewed footage of the attack, they realized the bubble wasn't blood; it was feces. The whales had unleashed a blast of poop at their attackers. Biologists call this technique defense defecation. The primary diet of sperm whales is squid, which accounts for the red color. Whatever the orcas thought it was, they weren't willing to endure it to continue the attack.
Sperm whales will also apparently use defensive defecation against annoying photographers.
Via Live Science