Hippos spray poop when they hear a hippo stranger

Hippos recognize strangers’ voice and respond in their own way

Hippos tend to poop significantly when hearing an unfamiliar hippo’s call. They do it to mark their territory.

Hippos’ social lives have been investigated in a study published in the journal Current Biology. The study took place in the Maputo Special Reserve in Mozambique, where numerous groups of hippos live in different lakes, allowing researchers the opportunity to record sounds from animals that lived close together as well as utter strangers.

The researchers recorded the animals’ reactions and played the calls for them. “We found that the vocalizations of a stranger individual induced a stronger behavioral response than those produced by individuals from either the same or a neighboring group”, said co-author Nicolas Mathevon of the University of Saint-Etienne. Hippos replied to the recordings by vocalizing back, approaching or spraying poop, or a mixture of these behaviors, but on hearing a stranger’s sound, the hippos were more likely to unleash stool.

The research could be useful if hippos need to be relocated to preserve their species. “Before relocating a group of hippos to a new location, one precaution might be to broadcast their voices from a loudspeaker to the groups already present so that they become accustomed to them and their aggression gradually decreases”, Mathevon suggests. The same might be done for the hippos that are being relocated, as an exercise for both parties to get to know each other.

The IUCN Red List of Threatened Species, which catalogs the conservation status of animals and plants, lists hippos as vulnerable species but the future investigations will help the researchers learn more about how hippos interact. Whether they’re using their mouths or their asses, they’re expressive animals.

Source cnet.com