Rare Tiger Born in San Francisco Zoo (PHOTO)

A rare Sumatran tiger cub has been born at the San Francisco zoo, and it's the first tiger born since 2008. Estimates state that there are only 400 Sumatran tigers in the wild; many are kept in zoos in order to help increase the population.

"These births are definitely rare," Dr. Tara Harris, a tiger specialist, told Reuters.

The cub belongs to mother Leanne, who has produced three male cubs for the San Francisco Zoo. Those cubs were all males and were transferred to other zoos throughout the United States to help with breeding and to raise awareness of the animals' rarity.

The Sumatran tiger is traditionally found in Indonesia but became listed as an endangered species due to excessive hunting, growth of oil palm plantations and illegal trading. While the country of Indonesia has explicitly banned the hunting and sale of tiger parts, it still continues on the black market.

Over 140 kilograms of tiger bones and 24 skulls were confiscated in Taiwan, according to one report by J. Ng. The bones fetch over $116 per kilogram, making them one of the most profitable exchanges.

The San Francisco Zoo is keeping an eye on the newborn cub, which will spend its first weeks with its mother in seclusion. Workers installed an infrared camera in the Lion House, which prevents visitors and workers from having much interaction with the tigers as they bond.

"All signs seem to be positive so far," Corinne MacDonald, San Francisco Zoo curator, told Reuters. "Mom and cub are bonding."

The cub will have its first examination in two weeks, at which point zoo workers will learn its sex. Until then, they are keeping their distance in order to ensure successful growth and "natural" bonding.

The San Francisco Zoo will keep the cub for nearly two years before deciding whether to transfer it to another zoo.