Man's shock find inside tiger shark: 'What the hell?'

The shark's reaction to a mouth full of spikes wasn't surprising – but the choice of meal certainly was.

A picture of the echidna was snapped just as it began to sink to the bottom. The side of the boat can be seen in the picture.
A picture of the echidna was snapped just as it began to sink to the bottom. Source: Nic Lubitz

Travelling between two tropical islands, a shark wrangler has witnessed what could be the most Aussie thing ever: A shark throwing up an echidna.

“At first I didn’t know what it was – I thought what the hell is this?” Dr Nicolas Lubitz recalled as he spoke with Yahoo News Australia.

“Then I realised it was a fully intact echidna. It had no signs of digestion, nothing, so it must have been snapped up just a couple of hours before we found it.”

When Lubitz spotted the tiger shark off the coast of Orpheus Island two years ago, he was a student at James Cook University. He was working to catch, wrangle and fit trackers to bull sharks, tiger sharks, rays and hammerheads as part of a monitoring project in waters between the Gold Coast and the Torres Strait.

Nicolas Lubitz touching a tiger shark in the ocean.
Nicolas Lubitz had fitted trackers to around 150 fish before the shark threw up the echidna. Source: Nic Lubitz

By the time he hauled in the tiger shark with a rope, he’d already handled around 150 other specimens. And he’d seen them bring up seabird feathers and pieces of dugong, but never an echidna.

In general, it’s “very rare” that a tiger shark will throw-up food at all, and when they do it’s usually a sign of stress or a sign that the meal isn’t sitting right.

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“I’ve never heard of it happening before and it’s probably not something that happens very often,” he said of the occurrence, which has been described as a one in a million event.

“I was quite stunned, and by the time I could grab my phone to take a picture it was already sinking to the bottom. But on the surface you could see all these spines floating around.”

Nicholas and two colleagues on a boat, fitting a tracker to a shark in the water.
Nicholas and his colleagues fitted trackers to over 800 sharks, fish and rays. Source: Nic Lubitz

Echidnas are known to swim, and sharks are opportunistic feeders – and in the case of the spiky echidna they’ll sometimes make unfortunate menu choices.

The tiger shark was caught in a narrow channel between two islands and Lubitz believes the echidna was likely swimming between them in search of food or a mate.

Nicholas putting a tiger shark back in the water. The image was taken from above. The water is blue.
The shark tracking program occurred between the Gold Coast and the Torres Strait. Source: Nic Lubitz

Lubitz believes the strange occurrence is a good reminder of the connection between the marine and terrestrial environments. “Things we do on land can impact marine mammals,” he said.

The discovery also highlights how many natural occurrences have yet to be documented by humans. “Even in the thousands of years that people have been looking at nature and trying to make sense of it, we’re still only scratching the surface of understanding,” he said.

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