Giant turtles eat baby birds

Giant turtles eat baby birds
Giant turtles eat baby birds
Anonim

Researchers in the Seychelles have filmed a giant turtle hunting a tern chick and devouring it in one gulp. Scientists who participated in this discovery say this is the first time that such an action has been filmed. But even they are shocked.

“It's totally amazing and rather terrifying,” said Justin Gerlach, an island ecologist based in Peterhouse, Cambridge, England. "The turtle deliberately chases this bird, kills it and then eats it. So yes, it's a hunt."

The giant turtles, now found only in the Seychelles and Galapagos Islands, were believed to be herbivores. In fact, their vegetarian diet is believed to have shaped their ecosystems like elephants or bison. But in an article published Monday in the journal Current Biology, Gerlach and Anna Zorah, a co-author with the Frigate Island Foundation, explain that there have been hints that heavy reptiles might supplement their diet from time to time. Turtles sometimes consume snail shells and bones from dead birds, goats, and even other turtles. But hunting?

It was rumored that turtles were chasing seabird chicks, which became helpless after dropping out of the nest. But so far no video has been received that captures a scene reminiscent of the story of P. D. Eastman's “Are you my mother?”, If Roald Dahl had written it, Gerlach believed any such observation was at best a misunderstanding.

"Nobody was looking for him, because why? Turtles don't hunt," Gerlach said. "You wouldn't waste time looking for a hunting turtle."

Now he wonders what else we can learn from these creatures, which can live for over 200 years and grow up to 500 kilograms.

"It's a pretty big mystery that they've solved here," said James Gibbs, a herpetologist at State University of New York and the Galapagos Conservatory of Music who was not involved in the study.

When Gibbs watched the footage, he was surprised at how slowly and awkwardly the attack was unfolding.

"It's a very interesting combination of diligence and incompetence," he said.

Gibbs studied giant tortoises in the Galapagos for about 30 years, where he says the turtles have an interesting relationship with birds.

"The turtles go up and extend all their limbs and tail, and the finches come and clean them of ticks," Gibbs said. "I've heard that sometimes turtles go down, flatten the finches and eat them."

But what happens in the video from the Seychelles is impossible to confuse. Indeed, scientists note that the turtle has indications that it has hunted seabird chicks in the past.

For example, when turtles eat leaves, grass, or fruit, they stick out their tongues and suck the food into their mouth. But the turtle in the video has its tongue pulled in and its eyes closed - signs that it is wary of a particular danger posed by this food source.

“It behaves differently from normal feeding,” Gerlach said. "It's not just gathering food. He kills to get food."

The fact that the giant tortoise is a female could be an important clue to the shocking behavior, Gibbs said. In island systems, as a rule, there is not enough calcium - an essential mineral for the formation of egg shells.

So while a video of a giant turtle attacking a helpless tern chick may be stressful for some people, the act of predation may just be one of the ways animals ensure the next generation's success.

"We used to think of them as not particularly interesting, slow and probably pretty silly," says Gerlach of the giant tortoises. "But obviously there is a lot more to these animals."

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