Giant pandas are naturally solitary animals that struggle to get into the mood to make love.
However, scientists are one step closer to decoding their strange sexual interactions having found males bleat and females chirp when things are about to get frisky.
A female panda is only on heat once a year for about 48 hours, making it hard for keepers to arrange mating or artificial insemination.
Experts believe decoding these peculiar love songs could help this rare species get intimate more often.
Giant pandas, scientific name Ailuropoda Melanoleuca, are solitary animals that typically avoid contact with one another outside of mating season.
Zoo keepers find it incredibly difficult to get them to mate in captivity.
‘Effective communication is, therefore, crucial for male and female giant pandas not only to locate opposite-sexed individuals for mating purposes, but also to overcome their natural avoidance and aggressive tendencies’, researchers led by Dr Benjamin Charlton at San Diego Zoo’s Institute for Conservation Research, California wrote in their paper.
Male giant pandas are known to bleat at high rates when they encounter females on heat, suggesting that these calls are important for coordinating mating activities.
According to their research, published in Royal Society Open Science, pandas use these strange noises to negotiate this delicate courtship process.
‘The giant panda’s most conspicuous vocalisation is a bleat that is thought to signal non-aggressive intent and promote contact between individuals’, researchers wrote.
‘Female giant pandas also produce high-pitched tonal vocalisations called chirps almost exclusively during their oestrus period’.
While chirping is relatively uncommon in males, both sexes also produce moans, roars, growls and squeals when they interact with one another.
Males and females often become aggressive towards one another if mating attempts fail, writes the Times.
They tend to honk more when they are alone, although the function of these honks is still unknown.
Scientists believe that barks, growls and roars are aggressive calls that are produced during antagonistic encounters.
Pandas produce squealing noises during or after a fight while they moan to show mild aggression.
Last month, scientists found that pandas could reveal their identity to nearby neighbours at distances of up to 65 feet (20 metres).
They can also identify the sex of nearby animals at distances of up to 30 feet (10 metres), the study found.
Signals contained in bleats about the identity and sex of the caller provide important information for pandas, which typically interact in dense bamboo habitats.
These bleats are used by the wild animals to identify potential mates — and avoid dangerous predators, scientists say.
Researchers from San Diego Zoo’s Institute for Conservation Research in California played back 100 bleats at varying distances to establish what information the endangered creatures gleaned from the noises.
They played 10 bleats from 10 adult giant pandas through a speaker.
The audio clips were re-recorded at distances of between 30 and 130 feet (10 and 40 metres) from the speaker, broken down into intervals of 30 feet (10 metre).
These recordings allowed experts to determine exactly what information was carried in the calls over various distances.