The Secret Language of Elephants

A new study has revealed that adult male African elephants emit a deep, resonant roar to herd members, signaling that it is time to move on.

Male elephants leave the herd when they reach maturity (around 10 to 19 years old), and usually live alone or in small groups.

Experts studied African bush elephants (Loxodonta africana) at the Mushara Waterhole in Etosha National Park, Namibia (one of the largest national parks in Africa).

They used recording equipment, including buried microphones and night-vision video cameras, to capture movements and sounds inaudible to human ears.

They noticed a distinctive rumbling noise that preceded the exit from the water hole, indicating that it had an important meaning.

Generally, the growl comes first from the largest or dominant male in the group, before being repeated by the rest of the males as a signal of readiness to exit.

“The new recordings show that there is much more going on in male elephant vocal communications than previously known,” said study leader Caitlin O’Connell Rodwell, a researcher at the Center for Conservation Biology at Stanford University.

"We found that this vocal coordination occurs in groups of individuals as evidence of rare close association," the research team said.

The team hypothesizes that male elephants may learn this behavior when they are young (from females), before they leave the herd.

"We think that as they mature and form their own groups, they adapt and use these learned behaviors to coordinate with the rest of the population," O'Connell-Rodwell said.

It is worth noting that the numbers of African elephants have declined over the past century, due to poaching and revenge killing resulting from crop monopoly and habitat fragmentation.

The study was published in the journal  PeerJ .