Isthmian-Atlantic Moist Forests Habitat
This taxon occurs in the Isthmian-Atlantic moist forests, an ecoregion covering the lowland Atlantic versant at chiefly below 500 metres elevation in southern Nicaragua, northern Costa Rica, and most of Panama; these moist forests represent the epitome of wet, tropical jungle. This forest ecoregion evolved from unique combinations of North American and South American flora and fauna, which came together with the joining of these continents around three million years before present.
The ecoregion is classified to be within the Tropical and Subtropical moist broadleaf forests biome. Currently, much of this ecoregion has been converted to subsistence and commercial agriculture. The Isthmian-Atlantic moist forests exhibit a high level of species richness, with 1021 vertebrate taxa alone having been recorded here, with a particularly vast assortment of amphibians, many of which are endemic or near endemic; moreover, among the amphibians there are many representatives of anuran, salamander and caecilian taxa.
This ecoregion located at the juncture of Central and South America. Condensation over the warm land produced by moisture-laden air from the Caribbean Sea colliding with the mountains produces constant high humidity and precipitation. Annual rainfall ranges from about 2500 millimetres (mm) in central Panama to over 5000 mm in southern Nicaragua. Basalt bedrock is the parent material of the residual and often unconsolidated soils covering the hilly areas of this ecoregion. Old alluvial terraces form the base of the swamp forests and flat lands in the lowest elevations and near the Caribbean Sea coast. The northern section of this ecoregion is formed of a wide, relatively flat alluvial plain, with a gradual elevation change from sea level to 500 metres in elevation
This ecoregion is characterised by a lush, high canopy tropical evergreen forest of huge buttressed trees reaching 40 metres (m) in height, and an associated rich epiphytic flora. The palm component includes many sub-canopy and understory species. Abundant subcanopy palm species are Amargo Palm (Welfia regia), Walking Palm (Socratea exorrhiza), and in permanently flooded areas, Raphia taedigera. Seasonal swamp forests occur in the lowest and flattest areas in Nicaragua and northern Costa Rica, particularly along the coastal zone, where they grade into mangrove forests. In these swamp forests, Gavilán Tree (Pentaclethra macroloba) dominates the canopy, along with Caobilla (Carapa nicaraguensis). The Almendro (Dipteryx panamensis) and the Monkey-pot Tree (Lecythis ampla) are two notable canopy emergents.
While small in areal size, the 1500 hectare La Selva Biological Station in northeastern Costa Rica hosts permanent populations of large predators such as the Jaguar (Panthera onca) and herbivores like Baird's Tapir (Tapirus bairdii), probably because of its biological corridor connection to the upper montane forests of Braulio Carrillo National Park. The Atlantic lowlands and middle elevations contain some of the rarest butterfly species in Central America and some of the world's highest butterfly species richness.
A considerable number of amphibian taxa occur in the ecoregion. Endemic anurans to the Isthmian-Atlantic moist forests include the Misfit Leaf Frog (Agalychnis saltator), which breeds in swamps, but lives mostly in the tree canopy; the Tilaran Robber Frog (Craugastor mimus); Diasporus tigrillo and the Cross-banded Treefrog (Smilisca puma), found only on the Caribbean versant of Costa Rica and Nicaragua. A further endemic frog to the ecoregion is the Rio Changena Robber Frog (Craugastor jota), narrowly limited to Río Changena, Provincia Bocas del Toro, Panamá. Other anuran species found here are: Veragua Robber Frog (Craugastor rugosus), a nocturnal anuran whose ova are laid in leaf litter; Agua Buena Robber Frog (Diasporus vocator), whose breeding occurs in bromeliads.
An endemic reptile found in the Costa Rican part of the ecoregion is the Viquez's Tropical Ground Snake (Trimetopon viquezi). Four taxa of marine turtles are found in the ecoregion's coastal zones, including the Green Turtle (Chelonia mydas EN), who may take almost six decades to reach sexual maturity; the Hawksbill Sea Turtle (Eretmochelys imbricata CR) is another marine species found here. In addition a number of freshwater turtles are found here such as the Brown Wood Turtle (Rhinoclemmys annulata LR/NT). Other reptiles found in the ecoregion include the Spectacled Caiman (Caiman crocodilus LR/NT); and Cienega Colorado Worm Salamander (Oedipina uniformis NT), a limited range amphibian found only in Costa Rica along slopes surrounding the Meseta Central.
- C.Michael Hogan and World Wildlife Fund. 2010. "Isthmian-Atlantic moist forests". Encyclopedia of Earth, National Council for Science and the Environment, Washington DC ed.Mark McGinley. updated 2013
- S.D. Davis, V.H. Heywood, O. Herrera MacBryde, J. Villa-Lobos and A.C. Hamilton, editors. 1997. Centres of Plant Diversity. A Guide and Strategy for their Conservation. Volume 3. The Americas. IUCN Publications Unit, Cambridge, U.K. 562 pp.