(CNN) -- A giant panda at the San Diego Zoo gave birth to a cub the size of a stick of butter on Wednesday, her fifth cub born in the zoo since 1999. The public can view live video of the cub and its mother, Bai Yun, on the zoo's Web site. The sex of the mostly hairless, pink newborn, which was born around 5 a.m., is not known yet, said Dr. Ron Swaisgood of the zoo's Institute of Conservation Research. It will take about one month for the iconic black-and-white coloration of the giant panda to become visible, Swaisgood said.
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Giant panda Bai Yun gives birth to fifth cub at the San Diego Zoo
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Bai Yun will care for the newborn by herself with zoo staff occasionally checking in
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Weighing around 300 pounds, Bai Yun is about 1,000 times the size of the cub
She raised all of her other cubs until about 1.5 years, the natural age for separation," Swaisgood told @placeholder.