Giant vegetarian tortoise breaks rank to eat meat. Video captured shows reptile deliberately attacking and eating chick

Zoologists captured the moment when a lifelong vegetarian broke rank to eat meat and what made it all the more “horrifying” was that it was a tortoise.

Researchers captured the moment on video when a Seychelles giant tortoise, previously thought to be vegetarian attacked and ate a tern chick in what they say is the first documentation of deliberate hunting in any wild tortoise species.

“This is completely unexpected behaviour and has never been seen before in wild tortoises,” Justin Gerlach, director of studies at Peterhouse, Cambridge and affiliated researcher at the University of Cambridge’s Museum of Zoology, said in a statement Monday.

“The giant tortoise pursued the tern chick along a log, finally killing the chick and eating it,” Gerlach, who led the study, published Monday in the journal Current Biology, said.

“It was a very slow encounter, with the tortoise moving at its normal, slow walking pace, the whole interaction took seven minutes and was quite horrifying.”

Though tortoises are thought to be vegetarian, they have been spotted “opportunistically” eating carrion, as well as bones and snail shells for calcium.

“It’s quite common for herbivores to eat a bit of dead animal as a free protein source, essentially. But this is the first video evidence of them deliberately killing in order to eat,” Gerlach said.

Still, the team can’t say for certain how common such behavior is among the tortoises, and plan to study them further.

Giant tortoises are the largest herbivores on the Galapagos and Seychelles islands, and eat up to 11% of the vegetation, researchers said.

Gerlach added that the tortoise’s behavior was unlikely to significantly affect tern populations.