For panda lovers (i.e. all people everywhere with hearts and eyes), the past week has been a bonanza: Two giant pandas gave birth at two zoos, and another tested positive for hormones that indicate she’s about to give birth at another zoo. It sounds like we’re in the midst of a captive panda population boom, which can only mean good things for the greater, endangered giant panda population, estimated to be smaller than 2,000.
But the reality isn’t quite as rosy. Studies have long shown that zoos are among the hardest places for pandas to reproduce naturally (most females in zoos are impregnated through artificial insemination) and scientists are now beginning to understand why.
According to a new study, captive male pandas are only interested in captive females when they have rivals, and in zoos they have none.
During mating seasons in the wild, scent is a key element in the mating process: Male pandas follow the scent of menstruating females, and are then prompted to compete with other males—in part by their smell.
But in zoos, the study found, male pandas don’t have the same odoriferous incentive, mostly because they’re housed individually and not exposed to rivals during mating season.
The next step, say the researchers at the China Conservation and Research Centre for the Giant Panda, is to attempt to trick captive male pandas by spraying their habitats with the scents of other males.
If this so-called rival simulation works, the end result could mean a more robust captive breeding program. And birthing more pandas in zoos will have a trickle-down effect, says Andrea Muller of Pandas International.
“The Smithsonian Zoo went absolutely crazy when their cub, Tai Shan, was born back in 2005,” she says. “I’m pretty certain donations (from visitors) came flooding in,” which were then filtered back into panda research and conservation, potentially leading to more births—and more pandas.