The montane forests that grow along the Magdalena river valley, on the inner slopes of the Eastern and Central Cordilleras, of the Northern Andes in Colombia, are very rich both in animal and plant diversity and endemic species. Being the Eastern cordillera of sedimentary origin, due the uprising of the highly volcanic Central cordillera, the soils are very diverse so the forests that grows on them. In the middle of the Magdalena Medio, surrounded by moist forests, rises the Serranía de San Lucas, up to 2,000 meters, little known biologically.
Location and General Description
Located between 1° 30’ and 8° 20’ N and along the 73° W, these montane forests have a wet climate, usually with cloud forests forming at around the 1,800-2,200 meters above sea level (masl) belt, and again above 2,800-3,200 masl belt. The climate is in general seasonally wet, being the rainy seasons between April and June, and October to December.
The soils of the eastern slopes of the Central cordillera are volcanic ashes, while the ones from the western slopes of the Eastern cordillera are mainly sedimentary. The watershed drains towards the Atlantic Ocean through the Magdalena River; other important tributaries of the Magdalena are: from south to north, the Suaza, the Saldaña, the Sumapaz, the Chicamocha, the Carare and the Cauca with the Nechí.
The vegetation on this forests are very diverse, being rich in both plant and animal life. The most dominant trees are Cedrela odorata, Juglans neotropica, Decussocarpus rospigliossi, Podocarpus oleifolius, Cordia alliodora, Quercus humboldtii, Aniba perutilis, Anacardium excelsum, Tabebuia serratifolia, Vochysia ferruginea, Jacaranda caucana, Tabebuia rosea, Hieronyma macrocarpa and palm trees such as Ceroxylon quindiuense, C. alpinum, C. parvifrons, C. sasaimae, C. vogelianum and Dictyocaryum lamarckianum. Several orchids are endemic to these ecosystems; Cattleya trianaei to the upper Magdalena and C. warscewickzii to the San Lucas – Nechi region; Odontoglossum crispum and Odontoglossum nobile, Miltoniopsis vexillaria and Masdevallia coccinea, among the best known.
There are several endemic areas within this ecoregion; the upper Magdalena, in the Huila territory, with species of birds such as Athene cunicularia tolimae or Euphonia concinna, and the Cattleya trianaei, the national flower of Colombia. In the hills along the cordilleras there are other endemics such as Ceroxylon sasaimae, Odontoglossum crispum, Heliconia reptans, H. oleosa, H. huilensis, H. mutisiana, H. laxa, H. estiletioides and H. abaloi.
Large vertebrates found in this forests are the mountain lion (Puma concolor), the spotted cat (Leopardus tigrina), the spectacled bear (Tremarctos ornatus), the spider monkey (Ateles geoffroyi), the Andean wolly monkey (Logothrix lagothricha lugens), the Colombian tapir (Tapirus terrestris colombianus), the mountain tapir (Tapirus pinchaque), the red brocket deer Mazama rufina, the pacarana Dinomys branickii, the mountain paca (Agouti taczanowskii), the red howler monkey (Alouatta seniculus) and several others; among the birds, the blue billed curassow (Crax alberti), the huamán or mountain eagle (Oroaetus isidori), the wattled guan (Aburria aburri), the yellow-eared parrot (Ognorhynchus icterotis) actually on the verge of extinction, the golden-headed quetzal (Pharomachrus auriceps), the crested quetzal (Pharomachrus antisianus), the Andean cock-of-the-rock (Rupicola peruviana) and many more. To this forests arrive several species of migratory song-birds and raptors such as the rose-breasted grosbeak (Pheucticus ludovicianus), the broad winged hawk (Buteo platypterus), the swainson’s hawk (Buteo swainsoni), the summer tanager (Piranga rubra) and others.
Among the species of special concern are the yellow-eared parrot (Ognorhynchus icterotis), the Colombia’s national flower (Cattleya trianaei) or Christmas orchid, the Andean rosewood (Aniba perutilis), the Andean wolly monkey (Lagothrix lagothricha lugens), the mountain tapir (Tapirus pinchaque), the spectacled bear (Tremarctos ornatus), the wax palms Ceroxylon spp. and more.
Few areas are still in good condition due to large scale use of the slopes for coffee growing and farming, but also because more than 70% of the Colombian population lives in this region. The best-preserved areas are the upper Magdalena around the Los Guacharos National Park; the slopes of Nevados del Puracé and Huila, and the Serranía de San Lucas. The remaining areas have forest fragments of variable size. Today many canyons, basins and forest fragments have the remaining biodiversity of the region and all of remains are in urgent need of conservation.
There are several parks in the upper Magdalena basin, such as Guácharos, Puracé, Huila, Hermosas, Nevados, Picachos, Sumapaz and Chingaza, that conserve most of the high montane forests, mostly above 3,000 masl, but unfortunately, below 2,000 masl there are few conservation figures or initiatives, besides an insipient movement of nature reserves of the civilian society that is aiming to protect most of the remaining fragments of native forests among a "sea of grasses and exotic conifers and eucalyptus". Besides protecting the remnant fragments of native habitats, forest corridors between fragments, conservation areas and altitudinal gradients should be established.
Types and Severity of Threats
If actual trends continue in the region, one could expect more contaminated waters and rivers, the destruction of many forest fragments, the extinction of many animal and plant species, specially amphibians, large mammals, several birds, aquatic life, several orchids and precious timber. The loss of biodiversity in general is expected for the near future.
The conversion of the remaining forest fragments into nature reserves or any other form of management and conservation is a trend in the civilian society of Colombia, that aims to preserve most of the fragments and water bodies within this ecoregion.
Justification of Ecoregion Delineation
These montane forests surround the Magdalena Valley, containing the transitional habitat between the distinct dry forests of the lowlands and the peaks of the northern Andes. This ecoregion is bound by the western slopes of the Cordillera Central and the eastern facing slopes of the Cordillera Oriental, and are flanked by páramo habitats on either side. Delineations for this ecoregion were derived at an ecoregion workshop for the Northern Andes, with the purpose of distinguishing these unique montane forests. Lower limits follow the 1,000 m elevational contour. Because this ecoregion is bound by high mountains, which are formidable barrier to distribution in many species, it retains many unique and endemic species assemblages occurring on an elevational gradient (high beta-diversity).
- Complejo Ecoregional de los Andes del Norte (CEAN). Experts and ecoregional priority setting workshop. Bogota, Colombia, 24-26, July, 2000.
- Hernández-Camacho, Jorge, et al. 1992; Regiones Biogeográficas de Colombia, en La Diversidad Biológica de Iberoamérica, Halffter, G., Editor. CYTED-D, México.
Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.