Warning: Extremely Cute Pictures of the New Cloudeds Born at the Zoo

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Three and a half-year-old clouded leopard Jao Chu (JOW-chew) marked this Valentine's day with a special gift: two new (adorable) baby cubs.

Born on Sunday evening at the Smithsonian National Zoo's Front Royal, Virginia campus, the two cubs (which are not yet named) weighed about a half pound each. As they become adults, they will grow to between 30 and 50 pounds each and measure up to five feet in length.

The birth marked the third time in the past year that Jao Chu and her male mate, Hannibal, have produced clouded leopard cubs. Last March, Jao Chu gave birth to two males; in July, she gave birth to a female cub named Baylie.

The two newborn cubs sleep at the Smithsonian National Zoo's campus in Fort Royal, Virginia. Courtesy of Megan Murphy.

Clouded leopards are one of the animals most "vulnerable to extinction" because of high rates of hunting and rapid removal of trees in their native Thailand.  Before the first Jao Chu birth in 2009, it had been 16 years since a clouded leopard cub was born at the conservation and research center. Scientists and researchers have struggled with breeding the animals because of high cub mortality, frequent loss of interest between mates and aggressive behavior of males.

It will probably be a while before visitors are able to see the two cubs in person. But until then, get your clouded leopard fix by watching leopards Tai, a male, and Mook, a female, play in the National Zoo's  Asia Trail.

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