[2] The ecoregion occurs in elevations ranging from 400 to 3,500 metres (1,300 to 11,500 ft) on the eastern slopes of the Andes in Bolivia, extending into a small portion of southeastern Peru.

Fog and rain deposited by northern trade winds contribute to the high humidity and precipitation of the Yungas.

[2] Mammals found in this ecoregion include the spectacled bear (Tremarctos ornatus), Geoffroy's cat (Leopardus geoffroyi), lowland tapir (Tapirus terrestris), jaguar (Panthera onca), jaguarundi (Herpailurus yagouaroundi), pacarana (Dinomys branickii), and dwarf brocket deer (Mazama chunyi).

[2] Interesting bird species include the diademed tapaculo (Scytalopus schulenbergi), green-capped tanager (Stilpnia meyerdeschauenseei), Andean cock-of-the-rock (Rupicola peruvianus), and southern helmeted curassow (Pauxi unicornis).

Steep terrain, high precipitation, and difficult access have kept much of this ecoregion in a natural state.