For many years, giraffes were widely considered largely silent creatures. This perception often arises because their vocalizations are typically quiet, infrequent, and sometimes fall outside human hearing. The question of whether these majestic animals truly make sounds has intrigued researchers. The truth behind giraffe vocalizations is more nuanced than commonly believed, revealing a complex communication system that has only recently begun to be understood.
The Sounds Giraffes Make
Giraffes produce a variety of sounds, challenging the belief they are mute. One notable vocalization is a low-frequency hum, primarily observed at night. This nocturnal humming typically occurs around 92 Hz, which is within the range of human audibility, though it is quite low.
Beyond humming, giraffes also emit other sounds. These include snorts and grunts, which are often low-pitched and guttural. They may also produce hisses, particularly when confronted with a threat. Other documented vocalizations include moans and grumbles, associated with discomfort. Young giraffes, or calves, have a broader vocal range, making bleats and mews when seeking attention from their mothers. Anecdotal accounts also mention coughs, growls, and whistle-like sounds.
When and Why Giraffes Vocalize
Giraffe vocalizations serve various social and survival purposes. The nocturnal hum, for instance, is theorized as a contact call, helping individuals stay connected when visibility is limited in the dark. This suggests giraffes rely on sound when visual cues are unavailable.
Giraffes also vocalize in distress or danger. They emit low-pitched grunts and snorts as warning signals to other herd members. Hissing sounds can deter predators or rivals. During mating season, male giraffes make “coughing” sounds to attract females. Mothers use specific sounds, such as low bellows or whistles, to communicate with their offspring.
Why Their Sounds Are Rarely Heard
Several factors contribute to why giraffe sounds are rarely heard by humans. Their vocalizations are infrequent, quiet, or at frequencies difficult for human ears to detect. For example, the nocturnal hum is audible but its low frequency (around 92 Hz) is at the lower end of human hearing.
The unique anatomy of giraffes also challenges sound production. Their remarkably long necks, up to 8 feet, mean air travels a significantly longer pathway from the lungs to the larynx. This extended distance reduces airflow velocity and pressure, making loud vocalizations difficult. The larynx and hyoid apparatus may not be optimized for powerful sound projection. Their vast, spread-out habitats and observation challenges also contribute to the mystery.