Tiger shark regurgitates whole echidna in shocking first sighting | CNN

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In what is thought to be the first encounter of its kind to be witnessed by scientists, a tiger shark has been spotted vomiting up a dead echidna whole off the coast of an Australian island.

Echidnas, dome-shaped mammals covered in spines, are common in Australia.

Researchers from James Cook University in North Queensland observed the rare occurrence while tagging marine life off the region’s Orpheus Island in May 2022, according to a university press release Thursday.

“We were quite shocked at what we saw. We really didn’t know what was going on,” marine biologist Nicolas Lubitz, a former PhD student at the university and a researcher at Biopixel Oceans Foundation, said in the release.

“When it spat it out, I looked at it and remarked ‘What the hell is that?’. Someone said to take a picture, so I scrambled to get my phone,” he continued, adding: “I managed to only get one picture, but you can see the outline of the echidna in the water.”

The echidna was dead and “fully intact” with “all its spines and its legs” when it was regurgitated by the three-meter-long (almost 10-foot) shark, according to Lubitz.

He said it is “rare” that tiger sharks throw up their food, although they can when stressed. “In this case, I think the echidna must have just felt a bit funny in its throat.”

The shark was not harmed by the encounter and was released back into the water by the team after being fitted with an acoustic tracker, according to the release.

A different shark that the team caught and tagged also made a “surprising” regurgitation, throwing up half a dugong, according to the release. A dugong is a herbivorous marine animal that is most commonly found in Australia.

“It threw up a big piece of blubber and then a full vertebral column,” said Lubitz, believing they belonged to a dugong calf.

Tiger sharks have gluttonous appetites, a habit of scavenging and are reputed for man-eating. They eat other sharks, fishes, sea turtles and seabirds, as well as consume garbage including coal, tin cans, clothing and bones.

They have even been documented swallowing license plates, small television screens and tires, according to the release. “I’ve seen videos of them eating a rock for no reason,” Lubitz added.

Tiger sharks are found in warm oceans worldwide. In May 2023, a kayaker fishing in shallow waters offshore in Windward Oahu, Hawaii, captured the frightening moment the animal rammed into his boat.