It is exactly such a project that Dr Stoeger and her team undertook in their research, the results of which are published today in BMC Research Notes. The researchers collected data from giraffes in three zoos in Berlin, Copenhagen and Vienna. Hundreds of hours of audio recordings were made of these giraffes, mostly recorded indoors at night, but also including recordings gathered outdoors during daylight hours.
The team then analysed these recordings, searching for acoustic structures that resembled possible communications. The vast majority of the recordings showed no evidence of any vocalisation patterns. Tedious perhaps, but in the end worthwhile. Amidst the many hours of recordings, the researchers found a number of instances of a vocal pattern which, based on its acoustic structure, could potentially function as communication between giraffes.
This pattern, recorded 65 times across all three zoos, was a kind of humming vocalisation with a rich harmonic structure never before documented in the scientific literature. I even purchased a handheld audio recorder for the journey. Unfortunately, I was on a strict budget and the tour guide was useless. We broke down besides a pride of lions which cost one day. The following day the guide was so lost in his phone he almost trampled a giraffe tower. It felt like when I was a child and had done something wrong.
The Serengeti is an enormous place and vehicles must stay on the trails. Giraffe were always visible upon the horizon. Every evening their poetic frames turned to silhouette against the setting sun. Maybe I was paranoid but it seemed that the giants were watching me with suspicion.
Unable to get close enough I started asking different guides, but the answers came in similes and maybes. Every single guide made up a different sound, from clicks to chomps to question marks. Then I found out. A dazzling giraffe crossed the trail in front of me and met my eye. To this day I am certain that this giraffe winked at me although one week in the Serengeti wilderness did detach me from everyday reality. In that single glance I knew.
I had my confirmation from an old Masai tribesman in Ngorongoro a few hours later. This was his reply to my question, what sound does a giraffe make. Giraffe, my friend, are silent animals. Quite apart from the brilliant fact that he counted his age by the number of rainy seasons, the answer was so obvious I felt stupid. Of all the giraffe sounds I had made and heard from others, the simple truth was something else: silence. I have followed giraffe sounds with keen interest.
Note, it is true that giraffe very occasionally make a short snort or grunt , possibly when threatened. Yet this sound is more like a human hiccup or burp, an involuntary sound that can pop out when the body is shocked. Nobody had ever provided evidence that giraffe make vocalizations as a means of communication.
Until , it was universally agreed that giraffe really are silent animals. But there was no definitive answer to why these giants are silent. The common scientific explanation for giraffe silence is to blame it all on those enormous necks. Giraffe are proven to have a voice box or larynx so they could make a sound. But…for any mammal to make noise they must pass air through their vocal cords, thus making them vibrate. Low-frequency noises are common in many animals, including the big cats. As well as their orchestral horns and trumpets, elephants make low-pitched infrasound that are far below the range of human ears.
These can travel up to ten kilometres across the savannah. Elephants are big and so are giraffe. And two plus two equals the popular hypothesis that giraffe also communicate with infrasound. One possibility is that, like elephants, giraffe have very large vocal folds in their voice box. All giraffes have vocal cords and make sound, but what sounds do they make?
And what do those sounds mean? That depends on the age of the giraffe. Empirical and anecdotal evidence from zookeepers and giraffe managers supports that mature giraffes primarily snort and grunt, but a recent eight-year-long, three-zoo study recorded over hours of a third sound—humming—heard only at night. Sometimes jokingly referred to as being similar to a husband's snore, this sound was described by a Wired article as being at the low-end level of human hearing at a frequency of about 92Hz.
This borders the frequencies often referred to as infra-sound. Check out the audio recording below! Recorded evidence suggests that as they mature, their vocabulary begins to consist primarily of infra-sound "whooshes" of air, or that nighttime "humming" discovered by researchers. However, young giraffes are a different matter.
That same data collected from zookeepers attributes as many as 12 different sounds to young giraffes. Young giraffes make all types of sounds, including grunts, moans, snores, bellows, snorts, coughs, bleats, mews, hissing, whistle-like cries, and flute-like sounds.
Note: The inaudible giraffe sounds mentioned above, giant air whooshes , although observed to be communications - have yet to be correlated with specific meanings. A study published by BMC Research Notes found that giraffes primarily use infra-sound to communicate. The study did not address the empirical research that has concluded that it is the young giraffes that make the most sounds humans can hear. Nor could they positively conclude that mature adult giraffe sounds are more limited in the sounds they make.
Zoo managers and giraffe keepers say they had never heard this humming until the researchers played the audio recordings, so they can't be certain it isn't just a version of giraffe snoring!
Giraffes will communicate alarm or danger by stamping their feet and emitting loud snorts or grunts. Occasionally they will use snoring and hissing sounds, but these are usually only heard during fights. Yes, male giraffes do fight, and yes, it is usually over mating.
Like mothers and their children everywhere, mama giraffes have a special set of sounds they use just with their offspring. They use loud bellows when searching for the kid s which can be heard as much as a mile away, and whistling or flute-like sounds for other communications, like calling them home. Pixabay CC Composite Image. It seems male giraffes are the fighters of the family. Although there are territorial fights and disputes, the most common cause for male-to-male fights and confrontations are over dominance in mating issues.
Giraffe fighting sounds are loud snorts and moans, with grunts thrown in, using a "danger" sound , to intimidate the other male. The following video shows aggressive male behavior that ends in the defeat of one of the males.
The giraffes in this scene are shown "swinging" their heads at each other. Giraffes use loud coughs to court the females they want to mate with. The louder, and more raucous the cough, the more ardent the desire. And of course, the bigger the male, the bigger the throat, and the more deep and impressive the resonating coughs.
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