A moderately long (~4-5 seconds in duration), very low frequency, distinctive rumble with a characteristically pulsating ‘put-put-put’ or ‘glug-glug-glug’ quality, only produced by an adult male during his heightened sexual and aggressive period of musth. Known as a Musth-Rumble, this call is associated with an increase in the rate of Urine-Dribbling and a particular ear flapping known as Ear-Waving. The calls of individual males are distinctive. Some males Musth-Rumbles are of short duration, while those of others are very long; some have a rolling quality while others are more pulsated, or may sound like water gurgling through a deep tunnel. The ‘classic’ Musth-Rumble is a long, low, pulsated, tonal call with considerable overlaying noise.
Male elephants tend to Musth-Rumble in specific contexts such as: During aggressive interactions with other males; when approaching a group of females; prior to and immediately after a Mating; when they Rub a tree with Temporal-Gland-Secretion, when Drinking, Mud-Splashing, or Mud-Wallowing, or in situations where they feel challenged. For example, the sound of another musth male, an approaching vehicle or even an airplane overhead is often enough to trigger a musth male to Musth-Rumble. Musth males also frequently Musth-Rumble before or after Listening, when they are presumably responding to distant elephant calls or using calling to search for potential mates.
Musth males most often Musth-Rumble when they are alone, less often when they are in the company of females and least often when they are Guarding an estrous female. Since musth males often Listen after they Musth-Rumble, it is likely that they use Musth-Rumbles to advertize their heightened aggressive and sexual state to rival males and to potential mates. Females respond to the Musth-Rumbles of musth males by Female-Chorusing, so calling may help a male to locate groups of females. Once a male has located an estrous female he may have neither the need nor the desire to advertise his whereabouts.
References: Poole 1982: 50, 51; Poole 1987; Poole et al 1988; Poole 2011. (Full reference list)
This behavior occurs in the following context(s): Advertisement & Attraction, Aggressive, Courtship