On Friday, July 15, staff at the Ellen Trout Zoo in Lufkin, Texas welcomed a new baby lion into the world. But this wasn’t any ordinary cub: Unlike both of its golden-brown parents, the Lufkin Daily News reports, the animal's fur was white—making it the second white lion cub to ever be born in an accredited U.S. zoo.

“I just couldn’t believe it, but it sure is white,” Gordon Henley, the director of the Ellen Trout Zoo, told ABC News affiliate KLTV. “It looks like a bunch of cotton balls all rolled up.”

The white lion cub’s pale fur was caused by a natural genetic mutation that’s only found in South Africa’s Greater Timbavati/Kruger Park region, Fox61 reports. Its parents passed the white fur gene down as a recessive trait, meaning both of them carried it, even though neither had a pale coat.

Workers at the Ellen Trout Zoo contacted a nonprofit called the Lion Species Survival Plan to see how common white lion births actually are. In 2014, another pale cub was born at the Omaha Zoo—but around six months later, its color had darkened to golden brown. Meanwhile, four white lions were born at the Toronto Zoo in September 2015.

According to estimates, fewer than 300 white lions live in captivity worldwide. And white lions are even more rare in the wild, Fox 61 reports: Data provided by the Global White Lion Protection Trust show that fewer than 13 white lions live in all of South Africa’s Timbavati bush region.

This was the second pregnancy for the cub’s mother, an African lion named Adia who gave birth to her first cub, Sangofour years ago. Sango had to be hand-reared because Aida didn’t produce milk. This time around, both Aida and the new baby are in good health, a post on the zoo’s Facebook page confirms.

For now, zookeepers have left the cub alone with Adia so she can bond with her baby. The cub’s name hasn’t been revealed yet, but zookeepers would be wise to hold off on giving it monikers like “Snowball”: Experts still don’t know yet whether the lion will stay white or if its coat will eventually turn a different shade. 

[h/t Lufkin Daily News]

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