You probably already knew that elephants trumpet, growl and make other audible sounds to communicate with each other.
But scientists working in Samburu have found that elephants also communicate a lot by thumping the ground to create vibrations, which we humans cannot hear.
Their study also suggests artificial vibrations from human developments like the standard gauge railway, may interfere with elephants communication and prove more disastrous than previously imagined.
For the first time, researchers captured powerful vibrations made through the jumbos’ heavy footsteps, compared that with animal behaviour, and confirmed they were indeed communicating.
They said such vibrations could be used to detect when elephants are in distress, for instance, while being attacked by poachers.
The ground vibrations were captured through tools designed to detect earthquakes.
“In Kenya, we recorded the ground-based vibrations of different wild elephant behaviours,” authors say in the study, published this month in Current Biology journal.
The authors are affiliated to Oxford University and collaborated with local NGO Save The Elephants in this study.
The two lead scientists, Dr Beth Mortimer and Prof Tarje Nissen-Meyer, along with two other researchers, worked inside the Samburu National Reserve to capture the ground-based vibrations.
They found that by recording the vibrations that elephants generate through the ground, they could classify particular elephant behaviours.
Computer models showed they could detect and classify particular behaviours over kilometres.
“Rapid running in elephants is a sign of distress or aggression, and we estimate that these high-force behaviours will propagate over many kilometres, potentially providing useful information to promote vigilance in spatially-separated elephant groups,” the authors say.
The findings also suggest that human-generated noise may heavily interfere with elephants' ability to communicate through vibrations.
This means developments like the SGR and roads in inside Kenya’s national parks will interfere with animal life in greater ways than previously believed.
“The impact of other noise on this mode of communication mode is particularly worrying given the increased levels of human-generated seismic vibrations in remote locations,” says Dr Mortimer.
Save The Elephants’ CEO Frank Pope, said: “Legends and folklore have long spoken about the way elephants can not only communicate across long distances, but also detect other events that shake the ground like far-off thunder. This study marks a new phase in trying to understand the nature of the vibrations elephants produce and how they might be used by elephants themselves. Along the way, it is opening our eyes to the challenges posed by human-generated noise in an increasingly crowded landscape.”
Elephants are the largest land mammals in the world. Their only predators are humans.