Bozo (sometimes Boso, 'house of straw') is spoken by the Bozo, the principal fishing people of the Inner Niger Delta in Mali. According to the 2000 census, the Bozo people number about 132,100. The Bozo dialect cluster is often considered to be one language, but there is quite a bit of diversity. Ethnologue recognizes four languages on the basis of requirements for literacy materials. Bozo is part of the northwestern branch of the Mande languages; the closest linguistic relative is Soninke, a major language spoken in the northwestern section of southern Mali, in eastern Senegal, and in southern Mauritania. The Bozo often speak one or more regional languages such as Bamana, Maasina Fulfulde, or Western Songhay. The language is tonal, with three lexical tones.