Elephants Choose the Best Time to Call Mates

Elephants Choose the Best Time to Call Mates

Namibian elephants emit low-frequency calls at specific times of the day when atmospheric conditions are most favorable for sound to travel long distances.

Professor Michael Garstang from the University of Virginia in the U.S. conducted a three-week study using a meteorological setup and eight microphones. The research revealed that 42% of elephant calls occurred during stable atmospheric conditions – specifically, three hours after sunset.

The second most common time for calls was about two hours after sunrise, when the atmospheric conditions were also optimal for sound propagation over long distances. Of the 1,300 calls recorded during the study, 94% occurred during these two periods.

Stable atmospheric conditions, also known as temperature inversions, occur when a cold layer of air near the ground is trapped beneath a warmer layer above, creating a boundary. This phenomenon is similar to the inversions seen in valley cities, where cold air mixed with pollution becomes trapped near the surface. Sound waves encountering this boundary are bent back toward the ground, allowing them to travel farther.

Such stable conditions, commonly observed in the Arctic, can enable human voices at audible frequencies to travel up to 3 kilometers.

In Namibia, however, the daily heating of the ground by the sun increases temperatures and disrupts these inversion layers, reducing the optimal conditions for long-distance calls. To test this hypothesis, Garstang’s team set up atmospheric measurement equipment and released weather balloons to record wind speed and temperature at different altitudes.

Elephants need to communicate over long distances to find mates. Female elephants have a very short window for reproduction and must locate the best possible male. The only way to achieve this is by producing low-frequency mating calls and listening for responses. This behavior highlights that elephants are aware of dawn and dusk being the best times to call out to one another.