LANHAM, Md. (CBSDC)- Twin Andean bear cubs born at the National Zoo in December received clean bills of health Wednesday.

A team of veterinarians performed a complete physical exam, which included listening to the cubs’ hearts and lungs, checking their mouths, eyes, legs and feet and feeling their bellies. The twins also received the first in a series of routine vaccines.

The veterinarians say it is hard to determine their genders at such a young age since their genitalia has not fully developed, but it appears that one is male and one is female. The larger cub weighs 10.1 pounds and the smaller one weighs 9.2 pounds.

The siblings have spent the past two months bonding with their mother, Billie Jean, in a den near the zoo’s American Trail exhibit. So far, the public has had the opportunity to watch Billie Jean give birth and watch the twins play and grow via the live Andean Bear Cub Cam on the zoo’s website.

The family’s public debut is slated for later this spring.

Andean bears, also known as spectacled bears, are listed as vulnerable on the International Union for Conservation of Nature’s Red List. It is estimated that there are only 2,000 left in their natural habitat. The information gathered from watching the cubs will be shared with the Association of Zoos and Aquariums for the benefit of other institutions that exhibit and want to breed the species.

To follow the bears’ progress yourself, watch them on the live webcam, read updates from the Andean bear keepers and check for news on the Zoo’s Twitter feed and Facebook page with the hashtag #cubwatch.

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