Hippos can recognise their friends' voices

By Helen.
Science correspondent.

The image is from Nicolas Mathevon.

There is an image caption.

The scientists studied the Hippos in the nature reserve.

Hippos are loud and travel long distances across lakes and rivers.

The function of the noise the animals make has been a mystery.

Hippos at a nature reserve in Africa have distinctive honks that allow them to tell a friend from a foe.

The team says the animals can probably hear voices.

Prof Nicolas Mathevon, from the University of Saint-Etienne in France, studied the sounds animals make across the world.

Hippos have a wide vocal range, but very little is known about their social communication.

He said that they are able to recognise each other by their voices because of the information they have about the individual. The social relationships between individuals are supported by this recognition ability.

The image is from Nicholas Mathevon.

There is an image caption.

There are a number of lakes with different hippo populations.

Researchers from France recorded the sounds of hippos in a special reserve.

According to the study, the most common call of the Hippo is the wheeze-honk.

The biologists broadcast the wheeze-honks of Hippos from the shore of lakes to see how other people responded.

Hippos could tell apart people from their voices. According to the researchers, the animals can tell apart friend from foe and also distinguish between individuals, though they can't be certain of this.

The large mammals were paying close attention to their surroundings and responded immediately to the broadcasts even though they appeared to be lounging around on the water.

The animals responded more aggressively to unknown Hippos, with louder and more frequent calls, and territorial displays of dung spraying.

Prof Mathevon said it was important to learn more about the biology and behavior of the Hippos.

He said that the knowledge could help with conservativism, as wild hippos are sometimes moved from one location to another to keep local populations healthy.

He said that the work may inspire them to make recordings to allow local Hippos to get used to the new ones before they arrive.

Hippos are not yet extinct in the wild. Hippos cause hundreds of human deaths a year and are a source of animal-human conflict.

Current Biology published the research.