The Magdalena Valley dry forests are located between the Eastern and Central cordilleras of the Colombian Andes, along the dry inter-Andean valley formed by the Magdalena River, which flows north through the Andes to the Caribbean Sea.
Magdalena Valley Dry Forests
The Magdalena Valley dry forests ecoregion is located between the Eastern and Central cordilleras of the Colombian Andes, along the dry inter-Andean valley formed by the Magdalena River, which flows north through the Andes to the Caribbean Sea.
The Magdalena Valley dry forests occur at about 450 m (1,475 ft) and have a dry climate receiving less than 1,000 mm (40 in) of rain annually. The ecoregion has an area of 19,748 sq km (7,625 sq mi).
The valley floor is flat, with fertile alluvial soils and large ash deposits from the Huila and Puracé volcanoes. As a result, the dry Tatacoa Desert holds many vertebrate fossils dating from the Miocene era.
The Magdalena Valley dry forests are almost surrounded by the Magdalena Valley montane forests ecoregion. The dry valley merges into the Magdalena-Urabá moist forests at its northern end.
Annual rainfall in the Magdalena Valley ranges from 831 - 2,268 mm (33 - 89 in), distributed over two distinct rainy seasons. The rainy seasons last from April to July and from October to December. Consequently, there is a water deficiency from April to September.
In the Tatacoa Desert, part of this ecoregion, there is less than 700 mm (28 in) of rain annually.
The mean annual temperature throughout the Magdalena Valley dry forests ecoregion is 26.8 °C (80.2 °F). However, temperatures rise to an average of 30 °C (86 °F) in July and August.
Flora and Fauna
Since the climate is dry, vegetation includes cacti such as Armathocereus humilis and Stenocereus griseus. Vegetation in the Tatacoa Desert is thorny, including cactus species such as Opuntia and Melocactus.
Also common are woody species of bushes and trees; wild lime, palo verde, sweet acacia, and the endangered Bulnesia carrapo endemic to Colombia.
The endemic and highly threatened "May flower" (Cattleya trianae) is the national flower of Colombia. Also, the national flower of Colombia grows along the transition between these dry forests and neighboring moist forests.
Fauna biodiversity is relatively unknown but includes a few endemic subspecies, such as the burrowing owl (Athene cunicularia tolimae), tropical bobwhite (Colinus cristatus leucotis), and euphonia (Euphonia concinna).
Agriculture and overgrazing, especially from introduced goats, have destroyed much of the original habitat. As a result, the World Wildlife Fund gives the ecoregion the status of "Critical/Endangered."
Map depicting the location of the Magdalena Valley dry forests (in purple)