Five tiny, endangered turtles hatched in Prospect Park Zoo last month.
This is the first time Chinese big-headed turtles has successfully hatched at a North American zoo, according to the Wildlife Conservation Society, which manages the zoo.
The turtles only grow to be about 7 inches long. Their skulls are so large in proportion to their bodies that their heads can't withdraw into their shells for protection.
The breeding is part of the conservation society's efforts to save endangered turtles from extinction.
"With so many of the world's freshwater turtles and tortoises facing extinction, these hatchlings represent significant progress for the conservation of the species," the zoo's director Denise McClean said in a statement.
Chinese big-headed turtles are native to China, Cambodia, Laos, Myanmar, Thailand and Vietnam. Their population is declining because of trade demand across range countries in Asia. They are often captured in the wild and sold in food markets.
The zoo was able to recreate natural breeding conditions, including mimicking seasonal environmental conditions from their Asian habitats. In the wild, turtles mate after hibernating in the winter.
The Wildlife Conservation Society has 15 of the big-headed turtles in the Bronx and Prospect Park Zoos.
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