The cry is known as a spacing call, a warning to other indris to keep their distance, to prevent competition for food.
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Large short-tailed lemur of Madagascar having thick silky fur in black and white and fawn
The Indri (Indri indri), also called the Babakoto, is one of the largest living lemurs. It is a diurnal tree-dweller related to the sifakas and, like all lemuroids, it is native to Madagascar.
Indri are the members of an ethnic group of Sudan. They live in Southern Sudan. Most of them are Muslims. The number of persons in this group is about 1,000. They speak Indir, an Adamawa-Ubangi language.
(INDRIS) Inland Navigation Demonstrator for River Information Services