The Peruvian yungas are sub-tropical montane deciduous and evergreen forests that flank the Peruvian Andes' eastern slopes and central valleys. This region maintains one of the richest montane forest ecosystems in the Neotropics.
The Peruvian yungas are sub-tropical montane deciduous and evergreen forests that flank the eastern slopes and central valleys of the Peruvian Andes from northernmost to southernmost Peru. The ecoregion occupies an area of approximately 188,735 sq km (72,870 sq mi).
This region maintains one of the richest montane forest ecosystems in the Neotropics. As a result, many species of plants, birds, mammals, reptiles, amphibians and invertebrates are found only in this part of the planet.
In the Peruvian yungas ecoregion, vegetation is highly diverse, forming an elaborate mosaic of Andean montane vegetation types ranging from montane forests, premontane and lowland forests, dry forests, and high-elevation woodlands.
In the Peruvian yungas, vegetation is highly diverse, forming an elaborate mosaic of Andean montane vegetation types ranging from montane forests, premontane and lowland forests, dry forests, and high-elevation woodlands.
The WWF has delineated three yungas ecoregions along the eastern side of the Andes range:
Most of the Peruvian yungas ecoregion lies on the sub-Andean strip, a mountainous region running parallel to and at the base of the eastern range.
The terrain is steep and rugged, and altitudes vary dramatically within the ecoregion, from high plains to precipitous valleys. The steep slopes, ridges, and valleys each contain unique microclimates.
Precipitation ranges from 500 - 2000 mm (19 - 79 in) annually, and deciduous trees occur in dry habitats. Otherwise, the region has lush, dense vegetation, high species diversity and richness, and many endemic species.
At altitudes above 2500 m (8,200 ft) asl, average temperatures range from 6 - 12 ºC (42 - 54 ºF) in the northern section and 8 - 22 ºC (46 - 72 ºF) in the southern section. In low areas, the average temperature is 25 ºC (77 ºF).
Flora and Fauna
The Peruvian yungas contain over 3,000 species of plants. Tree ferns (Cyathea) and bamboo (Chusquea) are common.
Below 2,700 m (8,900 ft), the forest includes species such as cedar (Cedrela), trumpet tree (Tabebuia), and relatives of papaya (Carica). Above 3,500 m (11,500 ft), there are scrublands and wet rocky thickets with shrubs and land orchids, as well as forests of Podocarpus conifers.
There are at least 200 species of orchids (such as the genera Epidendrum and Maxilaria). Below 3500 m (11,500 ft) are the so-called cloud forests with the presence of bamboo (Chusquea) and arboreal ferns (Cyathea spp.).
Below 2700 m (8,800 ft), the forest becomes richer in species such as cedar, cetico (trumpet-wood) and relatives of papaya (Carica spp). Above 3500 m (11,500 ft), there are scrublands, wet rocky thickets with some shrubs and land orchids, and forests of romerillo (Podocarpus).
The Peruvian yungas contain over 200 species of vertebrates. The gallito de las rocas (Rupicola peruviana) is endemic. Notable mammals include the shrew opossums (Caenolestes) and Kalinowski's Agouti (Dasyprocta kalinowskii), as well as the northern pudú (Pudu mephistophiles) and the hairy long-nosed armadillo (Dasypus pilosus).
Notable species with limited distributions found here include the horned curassow (Pauxi unicornis), hummingbirds (Metallura theresiae, Heliangelus regalis), the long-whiskered owlet (Xenoglaux loweryi), and the Marañón poison frog (Dendrobates mysteriosus).
Endangered and threatened species include the yellow-tailed woolly monkey (Oreonax flavicauda), jaguar (Panthera onca), ocelot (Leopardus pardalis), spectacled bear (Tremarctos ornatus), neotropical otter (Lontra longicaudis), colocolo (Oncifelis colocolo), Andean cock-of-the-rock (Rupicola peruviana), and cinchona (Cinchona sp.).
The Peruvian yungas ecoregion also has endemic butterflies from the genera Dismopha, Callithea, Paridos, and Morpho.
However, the ecoregion is considered a nearly critically endangered state due to migratory agriculture, coca production, deforestation, selective cutting, and gradual urban development.
Map depicting the location of the Peruvian Yungas (in purple)