HOUSTON -

The Houston Zoo welcomed two male clouded leopard cubs to its family last Friday.

The unnamed male cubs were born after an unassisted, one-hour labor by 2-year-old Suksn in a private den off-exhibit, according to the Zoo. Shortly after birth, the two cubs were moved to the veterinary clinic to begin receiving 24-hour care and the pair will remain behind-the-scenes for several months while they continue to grow and thrive.

The birth is the first clouded leopard birth for the Houston Zoo and for mother Suksn and the first offspring for the cubs' 2-year-old father, Tarak. Suksn and Tarak have been residents of the Houston Zoo since 2012.

The Zoo says the current protocol among zoos is to hand-raise all newborn clouded leopards.

Clouded leopards are vulnerable to extinction because of deforestation and hunting.