A critical breakthrough has been made in efforts to save the giant panda, one that could kick-start attempts to reintroduce the animals to the wild.
Conservationists say they have perfected the difficult task of reproducing pandas, having reached their target of successfully raising 300 of the bears in captivity.
The breakthrough, mainly by scientists at the Chengdu Panda Breeding Research Centre, China, should lead to the first panda being reintroduced into the wild within 15 years.
The revelation comes after documentary makers were given unprecedented access to the research centre to film captive breeding activity over two years.
Just a few thousand wild pandas survive at best, and the species is classified as being Endangered.
In a bid to protect the animal, scientists have attempted to breed captive pandas since the first such cub was born in 1963.
But many obstacles stood in the way of achieving a stable captive panda population.
The first was the very short window of opportunity provided in the panda's natural reproductive cycle.
Female pandas are only on heat for 72 hours a year, and can only actually become pregnant during a 12 to 24 hour window during this time.
In order to correctly interpret the bears' breeding potential, caring for captive female pandas required close observation including daily urine samples to monitor hormone levels.
Understanding the giant panda's natural patterns of reproduction was only the start of the challenge. BBC Earth News