Communication in Asian Elephants
Asian elephants are highly intelligent creatures with complex social lives and a hierarchical herd structure. To facilitate the creation and maintenance of such intricate social interaction, elephants have evolved a broad array of communication methods and techniques. These include communication methods which utilise senses we are familiar with as humans – sight, sound, touch, and smell – as well as specialised, sophisticated tools such as low-frequency infrasound, chemical signals, and the ability to detect underground vibrations.
The visual system of elephants is widely considered the least developed sensory system, and they rely far more heavily on their tactile and auditory systems for simple communication tasks. Despite a limited visual field, they do, however, possess satisfactory vision at close range, some colour vision, and even night vision. As such, elephants have developed a variety of gestures for communication, using almost every part of their bodies to signal messages to other elephants. For instance, an angry or threatened elephant may display this feeling by – among other, more subtle visual cues – lifting its head high, spreading its ears wide, shaking its head or tossing its trunk, raising its tail, or as a last resort, charging at the perceived threat.
For Asian elephants, auditory communication is extremely important, and the species has a vast and impressive repertoire of sounds for use in almost any situation. By manipulating their trunk position and airflow, as well as lengthening and shortening their vocal chords, elephants can produce a huge array of sounds in various frequencies. These include low-frequency infrasound rumbles as low as 12Hz (these are undetectable to humans, and are often used to alert herd members to the presence of predators or poachers), trumpets, chirps, cries, barks, and high-pitched roars, which can reach 470Hz and rise almost to the volume of a jet engine before take-off.
Non-vocal communication, such as touching and smelling with their trunks is another extremely important method of communication in Asian elephants. Touching helps to maintain social and familial bonds in herds through both direct tactile communication between the elephants making physical contact and acting as a visual cue to other nearby elephants, demonstrating the nature of their relationship, current feelings, and even their relative places in the social hierarchy. As with humans, frequent contact between a mother and her calf is essential to ensure effective communication and bonding. Touching and smelling between elephants is often accompanied by auditory communication, such as low growls or rumbles. As the most dexterous and versatile part of an elephant’s anatomy, the trunk is a vital tool for tactile communication. Upon meeting, elephants will use their trunks to stroke or caress other elephants as a form of introduction, and two elephants may intertwine their trunks as an act of greeting, mating ritual, or mild competition.
Asian elephants can also use their trunks to quickly express displeasure, such as using the trunk to discipline a young elephant with a slap. Elephants also use their trunks to slap the ground, creating a loud hollow sound accompanied by underground vibrations. This behaviour and sound can indicate to a nearby subject that the elephant is angry, especially in combination with visual cues such as ears spread wide and a raised tail, or it can be used to send a warning to other elephants at a distance.
Elephants can often be seen to touch the mouths, genitals, and temporal glands of other elephants with the tips of their trunks. This action allows them to pick up on chemical signals, another form of elephant communication. Perhaps the most significant of these chemical signals is contained in a think, strong-smelling fluid known as temporin, emitted from the temporal glands of bull elephants in musth. This substance is used to communicate dominance to other male elephants, and to attract females in oestrus, communicating sexual vitality. (You can read more about chemical and olfactory signalling in bulls undergoing musth here.) In addition to temporal gland excretions, sources of chemical communication include saliva, breath, urine, and faeces. Over millennia, Asian elephants have developed the ability to use their trunks in order to rapidly determine the fitness of individuals of the same sex, as well as to identify reproductive cues from members of the opposite sex, and precisely locate viable mates over great distances during critical reproductive periods.