The Asno de las Encartaciones is indigenous to the western part of the province of Biscay, and is concentrated in the municipalities of Artzentales, Balmaseda, Galdames, Gordexola, Güeñes, Karrantza, Lanestosa, Sopuerta, Turtzioz and Zalla.

[6] The Asno de las Encartaciones was presented at agricultural fairs in Gordexola in 1994 and at Markina in 1995.

As a result, a breeders' association, the Asociación para la protección y Defensa del Burro de Las Encartaciones, was formed in 1996, and a conservation plan, including a 12-hectare reserve at Gordexola, was published in 1999.

[2]: 45–46  No population data is published by the Ministerio de Agricultura, Alimentación y Medio Ambiente, the Spanish ministry of agriculture.

The coat is black or dark bay in colour; the belly, muzzle and surround of the eyes are pale-coloured.