| Cauca Valley dry forests | |
|---|---|
 Endemic grayish piculet | |
 Ecoregion territory (in purple) | |
| Ecology | |
| Realm | Neotropical |
| Biome | tropical and subtropical dry broadleaf forests |
| Geography | |
| Area | 2,800 km2 (1,100 sq mi) |
| Country | Colombia |
| Coordinates | 03°52′13″N76°21′13″W / 3.87028°N 76.35361°W Coordinates: 03°52′13″N76°21′13″W / 3.87028°N 76.35361°W |
| Conservation | |
| Conservation status | Critically endangered |
The Cauca Valley dry forests is a tropical dry broadleaf forest ecoregion in Colombia.
The Cauca Valley dry forests occupies an area of 7,300 square kilometers (2,800 sq mi), extending in a long, narrow strip along the Cauca River. The Cauca Valley is nestled between the Cordillera Occidental and Cordillera Central in the northern Andes. These ranges create a rain shadow, which makes the Cauca Valley drier than the surrounding forests. The Cauca Valley dry forests lie below 1000 meters elevation; the higher slopes are occupied by the distinct Cauca Valley montane forests. Most of these forests have been cleared for agriculture over the years making it one of the most critically endangered ecoregions in Colombia. Laguna de Sonso Nature Reserve has a small area of protected forest.
The ecoregion is part of the 103,000 square kilometres (40,000 sq mi) Tumbesian-Andean Valleys Dry Forests global ecoregion, which holds six terrestrial ecoregions: Tumbes–Piura dry forests, Ecuadorian dry forests, Patía Valley dry forests, Magdalena Valley dry forests, Cauca Valley dry forests and Marañón dry forests. The fauna and flora of the global ecoregion have high levels of endemism. [1]
The main plant communities are open woodland, deciduous dry forest, evergreen dry forest, riparian forest, arid scrub and wetlands. The natural vegetation has been almost completely displaced by human activities, chiefly agriculture.
Three endemic or near-endemic birds found in the ecoregion are the white-chested swift (Cypseloides lemosi), grayish piculet (Picumnus granadensis), apical flycatcher (Myiarchus apicalis).
The Cauca Valley dry forests have been mostly converted to agricultural fields. The city of Cali lies in the ecoregion.
The Sierra Nevada de Santa Marta is an isolated mountain range in northern Colombia, separate from the Andes range that runs through the centre of the country. Reaching an altitude of 5,700 m (18,700 ft) just 42 km (26 mi) from the Caribbean coast, the Sierra Nevada is the highest coastal range in the tropics, and one of the highest coastal ranges in the world, being 250 metres (820 ft) shorter than the Saint Elias Mountains in Canada. The Sierra Nevada encompasses about 17,000 km2 (6,600 sq mi) and serves as the source of 36 rivers. The range is in the Departments of Magdalena, Cesar and La Guajira.
The Tropical Andes is northern of the three climate-delineated parts of the Andes, the others being the Dry Andes and the Wet Andes. The Tropical Andes' area spans 1,542,644 km2 (595,618 sq mi).
The Ecuadorian dry forests (NT0214) is an ecoregion near the Pacific coast of the Ecuador. The habitat has been occupied by people for centuries and has been severely damaged by deforestation, overgrazing and hillside erosion due to unsustainable agriculture. Only 1% of the original forest remains. The patches of forest, mostly secondary growth, are fragmented. They are home to many endemic species at risk of extinction.
The Tumbes–Piura dry forests (NT0232) is an arid tropical ecoregion along the Pacific coasts of southern Ecuador and northern Peru. The ecoregion contains many endemic species of flora and birds adapted to the short wet season followed by a long dry season. Threats include extraction of wood for fuel or furniture, and capture of wild birds for sale.
The Marañón dry forests (NT0223) is an ecoregion in northern Peru. It covers the lower valley of the Marañón River and its tributaries along the eastern edge of the Andes. It has a dry climate due to rain shadow from mountains further east. The habitat has long been modified by farming, ranching and logging and is now threatened by construction of hydroelectric and irrigation dams.
The Patía Valley dry forests (NT0225) is an ecoregion in southwestern Colombia. It covers a dry valley surrounded by mountains. The original habitat has mostly been destroyed by human activity, although a few pockets remain.
The Magdalena Valley dry forests (NT0221) is an ecoregion in Colombia along the upper Magdalena River, a large river that runs from south to north between the two main cordilleras of the Andes. There are many endemic species, but much of the original habitat has been destroyed by agriculture and over-grazing, mainly by goats. The habitat is not protected by any national park, and is at risk of complete destruction.
The Northern Andean páramo (NT1006) is an ecoregion containing páramo vegetation above the treeline in the Andes of Colombia and Ecuador. In the past, when the climate was cooler, the treeline and the páramo units were lower and the units were connected. During the present warmer Holocene epoch the páramos have migrated uphill, shrinking and becoming isolated. They contain many rare or endangered species, some of them restricted to a narrow area of one mountain or mountain range. The ecoregion is relatively well preserved, but faces threats from over-grazing and farming.
The Santa Marta páramo (NT1007) is an ecoregion containing páramo vegetation above the treeline in the Sierra Nevada de Santa Marta mountain range on the Caribbean coast of Colombia. The isolated position of the range has allowed unique species to evolve. Some are related to those found in Central America and the Caribbean coastal areas, and some to species from the Andes. The habitat is relatively stable, but has been drastically changed from the original by long-term human activity.
The Cordillera Central páramo (NT1004) is an ecoregion containing páramo vegetation above the treeline in the Andes mountain range of northern Peru and southern Ecuador. Due to its isolation there are high levels of endemism. Despite many human settlements and some destruction of habitat by agriculture and mining, the ecoregion is relatively intact.
The Venezuelan Andes montane forests (NT0175) is an ecoregion in the northern arm of the Andes in Venezuela. It contains montane and cloud forests, reaching up to the high-level Cordillera de Merida páramo high moor ecoregion. The forests are home to many endemic species of flora and fauna. Their lower levels are threatened by migrant farmers, who clear patches of forest to grow crops, then move on.
The Cordillera Oriental montane forests (NT0118) is an ecoregion in Venezuela and Colombia along the east slopes of the eastern cordillera of the Andes. The extensive region of submontane and montane forests includes distinctive flora and fauna in the north, center and southern sections. The ecoregion is home to numerous endemic species of fauna. Despite extensive changes due to logging, farming and ranching, large areas of the original habitat remain intact, and the ecoregion has rich biodiversity.
The Catatumbo moist forests (NT0108) is an ecoregion in Venezuela and Colombia to the west and east of Lake Maracaibo. It includes four regions of moist forest on slightly higher ground than the dry forest and mangroves that surround the lake. The forest has unique flora related to the flora of the Amazon basin. It is badly degraded due to farming, livestock grazing and oil exploration.
The Bolivian montane dry forests (NT0206) 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.
The Chocó–Darién moist forests (NT0115) is an ecoregion in the west of Colombia and east of Panama. The region has extremely high rainfall, and the forests hold great biodiversity. The northern and southern parts of the ecoregion have been considerably modified for ranching and farming, and there are threats from logging for paper pulp, uncontrolled gold mining, coca growing and industrialisation, but the central part of the ecoregion is relatively intact.
The Northwestern Andean montane forests (NT0145) is an ecoregion on the Andes mountains in the west of Colombia and Ecuador. Both flora and fauna are highly diverse due to effect of ice ages when the warmer climate zones were separated and the cooler ones combined, and interglacial periods when the reverse occurred. Because the environment is hospitable to humans, the habitat has been drastically modified by farming and grazing since the Pre-Columbian era.
The Magdalena Valley montane forests (NT0136) is an ecoregion in the Andes mountains of central Colombia.
The Cauca Valley montane forests (NT0109) is an ecoregion in western Colombia. It covers the sides of the Cauca Valley, which runs from south to north between the Central and Western Ranges (cordilleras) of the Colombian Andes. The ecoregion is home to very diverse fauna and flora, due in part to its varied elevations and climates, in part to its position near the isthmus of Panama, the route along which North American species invaded South America and then diversified as they moved to the upper parts of the Andes. Little of the original habitat remains at lower levels, but higher up there are sizeable blocks of forest, some of which ate protected.
The Santa Marta montane forests (NT0159) is an ecoregion in the Sierra Nevada de Santa Marta, a massif on the Caribbean coast of northern Colombia. The ecoregion covers altitudes from near sea level up to around 3,300 metres (10,827 ft), where it gives way to Santa Marta páramo. The isolation of the massif and the range of elevations and climates has resulted in a wide variety of species including many endemics. The lower levels contained tropical rainforest, which has largely been cleared. Higher up, this gives way to cloud forest. Much of this has also been cleared for coffee plantations, pasture for sheep and cattle, and farming.
The Eastern Cordillera Real montane forests (NT0121) is an ecoregion in the eastern range of the Andes of southern Colombia, Ecuador and northern Peru. The ecoregion covers the eastern slopes of the Andes, and includes montane forest that rises from the Amazonian rain forest, with cloud forest and elfin forest at higher elevations. It is rich in species, including many endemics. It is threatened by logging and conversion for pasturage and subsistence agriculture.
