The National Zoo announced Friday that its six-year-old Andean bear is pregnant with two cubs.
Zoo veterinarians and keepers began to suspect that the bear, Billie Jean, might be pregnant in early November. A recent ultrasound showed two small amniotic sacs that have since shown growth and development.
In addition, keepers say that Billie Jean is showing similar behavior to the last time she gave birth, in January of 2010. In particular, they say Billie Jean's appetite has decreased, she's built a nest, and she's spending more time indoors, even when she is given outdoor access. Officials say that those behaviors all point to an impending birth, though they remain cautiously optimistic.
Billie Jean also gave birth to a pair of cubs the last time she reproduced. The names chosen by the public via an online poll were Chaska and Bernardo.
The Zoo has set up a live camera in Billie Jean's den, which can be viewed here.
Andean bears (also known as spectacled bears due to the distinct markings around their eyes) are listed as a vulnerable species by the International Union for Conservation of Nature. It is estimated that there are only 2,000 of them left in their habitat, which extends from Venezuela south to Bolivia. Sights have been reported as far south as Argentina and as far north as Panama.
The announcement of Billie Jean's pregnancy comes less than three months after a giant panda cub died at the zoo a week after it was born.