Two boatloads of tourists were on a cruise to Dirk Hartog Island when they spotted the dozens of sharks ripping the giant humpback whale cascass to shreds.
The spectacle turned the pristine waters of the aptly named Shark Bay to a crimson red.
Eco Abrolhos, which operates cruises to the Abrolhos Islands and Kimberley in Western Australia, sent up a drone to capture nature taking its course.
The firm posted the video on its Facebook page, with passenger Leesa Franks commenting: "We like, liked, liked. Awesome day yesterday, thanks so much."
Shark Bay is a World Heritage-listed area around 500 miles north of Perth and is home to an amazing array of marine life including whales, sharks, dolphins, dugongs and turtles.
