It’s a challenge to be optimistic about endangered species, but giant panda conservationists have reason to be hopeful.

In 1996, only 120 of the sweet-looking animals existed in breeding facilities and zoos.

The goal was to reach 300 in 25 years, a target set by scientists who believe the figure will be enough for the pandas to become a self-sustaining entity.

That number was accomplished last summer, more than a decade ahead of schedule.

The new objective, said Dr. Rebecca Snyder, curator of mammals at Zoo Atlanta, is for the pandas in captivity to maintain 90 percent genetic diversity for the next 200 years.

In 2010, Mei Lan, the first panda cub born at Zoo Atlanta, was flown to Chengdu Research Base of Giant Panda Breeding in China to become a candidate for breeding.

Since then, Zoo Atlanta’s adult pandas, Lun Lun and Yang Yang, have also become parents to Xi Lan and Po, who turns 1 in November. All four remain at the local zoo.

Snyder talked about the current state of panda conservation Thursday at the Association of Zoos and Aquariums 87th Annual Conference being held at Georgia World Congress Center this week.

The conference, which attracts about 2,000 attendees, is taking place in Atlanta for the first time in 17 years; it’s also the first time a zoo and aquarium are co-hosting the event.

At the “More Than Just A Pretty Face: Giant Pandas as an Effective Conservation Program” panel, Snyder was joined by peers from the other three U.S. zoos that currently house giant pandas: Dr. Andy Kouba, director of conservation and research at Memphis Zoo; Dr. Bob Wiese, chief life science officer at San Diego Zoo; and Dr. Melissa Songer, conservation GIS lab manager at Smithsonian Conservation Biology Institute at the National Zoo in Washington D.C.

Also present were Dr. Joe Heimlich, a professor at Ohio State University’s School of Environment and Natural Resources and Laurel Askue, manager of education marketing and development at Zoo Atlanta.

The pair discussed the development of the Academy for Conservation Training, a program developed at Zoo Atlanta in 2006 by invitation of the Chinese Association of Zoological Gardens to establish the profession of zoo education in China.

Through seven training sessions, 269 people have graduated.

“During the first training, we realized we were teaching trainees out of their comfort zone, but they became a strong support group among themselves and a strong network for Chinese educators,” Heimlich said.

Kouba, meanwhile, explained how the recent discovery of certain digestive bacteria in panda excrement might become a way to manufacture biofuel, and Wiese noted that radio collars equipped with GPS technology have been an important method of studying wild pandas.

“Fifteen or 20 years ago, people were saying there is no hope for the panda,” Wiese said. “But in a short time, I think we’ve shown that there is.”