Bolivian and Argentine yungas

Country/Territory Argentina,Bolivia
Area 60,000 km2
Altitude 800 - 3400m
Priority urgent
Habitat loss moderate
Knowledge incomplete

General characteristics

The yungas region essentially refers to the eastern slope of the Andes of extreme south-east Peru, Bolivia and Argentina. This particular EBA extends from Chuquisaca department of Bolivia, south through Tarija and the Argentine provinces of Jujuy, Salta, Tucumán, Catamarca and La Rioja. The altitude ranges from 800 m in the foothills up to 2,500 m, but sometimes reaches as high as 3,100 m. The northern end of the EBA is on the southern slope of the Cordillera Oriental of Bolivia, which branches out from the main Andean range running west to east. The northern slope of the Cordillera Oriental abuts the southern end of the Bolivian and Peruvian lower yungas (EBA 054). Adjacent to this EBA is the bottom end of the southern High Andes of Bolivia and Argentina (EBA 056 in part).

The climate is wet and humid with over 2,500 mm of rain annually brought along northerly trade winds. Correspondingly the vegetation consists of various evergreen forest formations, all of them with canopy heights not usually over 15 m. At higher altitudes, mainly between 1,200 m and 2,500 m, the forest is dominated by Andean alder Alnus acuminata, Podocarpus or pines. At lower altitudes these species are admixed with other trees, especially from the families Lauraceae and Myrtaceae.

Restricted-range species

The restricted-range bird species occur largely in the humid forests of the EBA, of which alder forest is especially important for Amazona tucumana and Cinclus schulzi, the latter being found always along fast-flowing streams in these forests. Atlapetes citrinellus shows the broadest habitat requirements, being found in hedgerows in agricultural areas, dense scrub and burnt forest as well as in coniferous and humid forests. C. schulzi winters at lower altitudes (to 800 m), and A. tucamana in other forests as low as 300 m. Elaenia strepera is an austral migrant, breeding only in this EBA and apparently wintering 3,000 km to the north in Venezuela (Marantz and Remsen 1991).

Species IUCN Category
Red-faced Guan (Penelope dabbenei) LC
Rothschild's Swift (Cypseloides rothschildi) NT
Blue-capped Puffleg (Eriocnemis glaucopoides) LC
Tucuman Amazon (Amazona tucumana) VU
White-throated Antpitta (Grallaria albigula) LC
Zimmer's Tapaculo (Scytalopus zimmeri) LC
White-browed Tapaculo (Scytalopus superciliaris) LC
Slaty Elaenia (Elaenia strepera) LC
Rufous-throated Dipper (Cinclus schulzii) VU
Yellow-striped Brush-finch (Atlapetes citrinellus) LC

Important Bird Areas (IBAs)
IBA Code Site Name Country
AR011 Alto Calilegua Argentina
AR012 Pampichuela Argentina
AR014 San Francisco-Río Jordan Argentina
AR015 Parque Nacional Calilegua Argentina
AR016 Yuto y Vinalito Argentina
AR018 Lagunas San Miguel y El Sauce Argentina
AR020 Tiraxi y Las Capillas Argentina
AR021 Reserva Natural Las Lancitas Argentina
AR022 Yala Argentina
AR023 Sierra de Zapla Argentina
AR024 El Fuerte y Santa Clara Argentina
AR025 Cerro Negro de San Antonio Argentina
AR026 La Cornisa Argentina
AR027 Acambuco Argentina
AR028 Itiyuro-Tuyunti Argentina
AR030 Santa Victoria, Cañani y Cayotal Argentina
AR031 Río Seco Argentina
AR033 Parque Nacional Baritú Argentina
AR034 Parque Provincial Laguna Pintascayoc Argentina
AR037 Fincas Santiago y San Andrés Argentina
AR038 Abra Grande Argentina
AR039 Río Santa María Argentina
AR045 Parque Nacional El Rey Argentina
AR046 Palomitas y Ebro Argentina
AR050 Cuesta del Obispo Argentina
AR078 Cuesta de las Higuerillas Argentina
AR080 Cuesta del Totoral Argentina
AR083 Trancas Argentina
AR087 Sierra de San Javier Argentina
AR090 Parque Provincial Los Ñuñorcos y Reserva Natural Quebrada del Portugués Argentina
AR091 Río Los Sosa Argentina
AR092 Parque Provincial La Florida Argentina
AR093 Parque Nacional Campo de los Alisos Argentina
AR094 Cuesta del Clavillo Argentina
AR095 Reserva Provincial Santa Ana Argentina
BO021 Reserva Biológica Cordillera de Sama Bolivia
BO042 Reserva Nacional de Flora y Fauna Tariquía Bolivia
BO046 Serranía de Aguarague Bolivia

Threat and conservation

It has been estimated that as much as 60% of the forest in the yungas of Argentina has disappeared (Vervoorst 1979). There are no estimates for the Bolivian part of the EBA, but recent ornithological surveys (e.g. Fjeldså and Mayer 1996, Tyler and Tyler 1996) have noted large areas of degraded land within the humid yungas-though there are also extensive forests remaining such as a 1,300 km2 tract between the Pilcamayo and Pilaya rivers in Montes Chapeados. Natural forests in Argentina have disappeared mainly through logging of valuable woods, conversion for agriculture, and plantations of exotic pines Pinus; road-building, human colonization and uncontrolled tourism have further increased habitat destruction (WWF/IUCN 1997).

The alder forest zone is especially important for the threatened Cinclus schulzi; its riverine habitat is endangered by reservoir construction, hydroelectric and irrigation schemes, eutrophication, deforestation and stock-grazing (Tyler and Tyler 1996).

There are a number of protected areas overlapping with the EBA, several of which are known to hold the restricted-range birds. These include Tariquía National Reserve (2,469 km2) in Bolivia, and Calilegua National Park (760 km<+>), Baritú National Park (724 km2), El Rey National Park (442 km2) and Potrero de Yala Provincial Park (43 km2) in Argentina. Importantly, there is a proposal currently being considered by Tucumán provincial government in Argentina to create the Campo de los Alisos National Park (2,500 km2), which would cover much of the Sierra de Aconquija (Halloy et al. 1994). This national park would secure protection for populations of all the restricted-range species of this EBA (as well as several species from the High Andes of Bolivia and Argentina, EBA 056).

Recommended citation
BirdLife International (2023) Endemic Bird Areas factsheet: Bolivian and Argentine yungas. Downloaded from http://www.birdlife.org on 28/01/2023.