快猫短视频

Giant panda sex is a noisy affair: the males bleat and the females moan. Now a new study has identified which panda calls are most likely to indicate a pair has actually mated 鈥� and which calls mean the pandas abandoned the attempt. This could help zookeepers and conservations as they build up the captive population and attempt to reintroduce giant pandas to the wild.

鈥淢ost people think of pandas as just sitting there and eating 鈥� which is true 99 per cent of the year. Then the one week they鈥檙e being introduced to each other, they鈥檙e really noisy,鈥� says Meghan Martin-Wintle at the San Diego Zoo. She recorded calls from 23 adult giant pandas housed in conservation centres in China between 2015 and 2018.

The vocalisations during 21 breeding sessions included bleats, chirps, moans, barks and roars. Martin-Wintle and her colleagues analysed subtle changes in pitch and the duration of 2566 individual calls, and then determined which ones were associated with breeding sessions that led to copulation.

鈥淭he duration depends on the male and female, how excited the pair is,鈥� says Martin-Wintle. When they copulate, she adds, the male bleat can get quite high in pitch and some individuals sustain the call for more than 20 seconds. 鈥淚t鈥檚 sounds like a goat [bleat],鈥� she says.

Both male and female bleats were associated with successful breeding. Female moans were also strongly associated with successful breeding. Female roars, on the other hand, were associated with breeding failure 100 per cent of the time. Female barks and chirps were also heard more during unsuccessful breeding.

鈥淏efore this, I would have also associated chirping with successful breeding,鈥� she says. 鈥淚鈥檝e always referred to it as the 鈥榗ome hither鈥� call, because it indicates that the female is trying to get the male鈥檚 attention. But it may show that the male is actually not all that interested.鈥�

Before copulation, male bleats were longer, which Martin-Wintle and her team say could encourage close contact by reassuring female pandas that the male isn鈥檛 aggressive.

An acoustic analysis of the panda calls found that females produced lower-pitch bleats when getting ready to copulate. These subtle acoustic changes have been shown to differentiate males from females, and could be used by female giant pandas to assure their potential mates that they are indeed female. That may increase the chances of breeding, as well as limiting aggression from a male.

As panda populations rebound from the brink of extinction, knowing how their calls relate to their attempts to procreate can help conservationists track the animals in the wild with sound-recording collars, says Martin-Wintle.