Bolivian montane dry forests


The Bolivian montane dry forests is an ecoregion in Bolivia on the eastern side of the Andes. It is a transitional habitat between the puna grasslands higher up to the west and the Chaco scrub to the east. The habitat is under severe stress from a growing human population.

Geography

Location

The ecoregion is in the dry mountain valleys of the Andes in southern Bolivia. It has an area of. In the south large areas of the ecoregion are found within the Central Andean puna and Southern Andean Yungas. To the east the dry forests transition into the Dry Chaco ecoregion. Further north smaller areas of the ecoregion are found in contact with the Central Andean dry puna, Central Andean wet puna and Bolivian Yungas.

Terrain

The terrain is rugged, with cliffs, steep hillsides, valleys and gullies.
Altitudes are from above sea level.
In the east fingers of the dry forest stretch into the yungas, while in the west fingers of puna grassland extend into the dry forest.

Climate

At a sample location at the Köppen climate classification is "Cwb": warm temperate, winter dry, warm summer. At this location the mean monthly temperatures range from in July to in November.
Yearly total precipitation is about. Average monthly precipitation is below in May–August, and rises to in January.

Ecology

The ecoregion is in the neotropical realm, in the tropical and subtropical dry broadleaf forests biome.

Flora

The dry forest ecoregion is a transitional habitat between the puna grasslands higher up to the west and the Chaco scrub to the east. It contains dry slopes with scattered shrubs and columnar cacti, seasonal dry forest and wetland forest along river courses. Where the spiny forest has been unaltered it holds species such as Vachellia caven, Prosopis alpataco, Dodonaea viscosa, Schinopsis marginata and Aspidosperma quebracho-blanco.

Fauna

Several mammal species more common in the tropics are at the southern limit of their territory in the ecoregion. There appear to be a variety of feline species including cougar, ocelot, Pampas cat, Geoffroy's cat and jaguarundi. Endangered mammals include the Bolivian chinchilla rat and short-tailed chinchilla.
Endemic birds include the Bolivian recurvebill, Bolivian blackbird, citron-headed yellow finch, Cochabamba mountain finch, Bolivian warbling finch, torrent duck, wedge-tailed hillstar, black-hooded sunbeam and grey-bellied flowerpiercer. Endangered birds include the red-fronted macaw and Bolivian spinetail.
Endangered amphibians include the frog Telmatobius sibiricus.

Status

The subtropical lower montane dry and moist life zones in the deep valleys between the mountains of the eastern Cordillera include the towns of Comarapa, Independencia, Totora, Tapacarí and Arque. These are the most favorable areas for human settlement, and have long been farmed, leaving little of the original vegetation.
The World Wildlife Fund gives the Bolivian montane dry forests ecoregion the status of "Critical/Endangered". The growing human population is creating urban sprawl and over-hunting, collecting wood for fuel and converting land for agriculture, causing habitat fragmentation.
Protected areas include the Madidi National Park and the Cordillera de Sama Biological Reserve. Others are the Tariquía Flora and Fauna National Reserve and Torotoro National Park.