Biological Importance

The Mesoamerica hotspot includes all tropical and subtropical natural plant formations from the Panama Canal west and north through Costa Rica, Nicaragua, Honduras, El Salvador, Guatemala and Belize, and southern and central Mexico as far as northern Sinaloa (Río Fuerte) on the Pacific coast and the middle of the Sierra Madre Occidental west of Tampico on the Gulf Coast. It includes all tropical and subtropical moist and dry forest zones usually considered part of the Neotropical region, but not the truly Nearctic (warm temperate) regions of northwestern Mexico.

The hotspot covers all of Central America (except for the region east and south of the Panama Canal, which is included in the Chocó-Darién-Western Ecuador hotspot); the Mexican states of Chiapas, Tabasco, Colima, Veracruz, Oaxaca, Campeche, Yucatán, Quintana Roo; and parts of the Mexican states of Jalisco, Guerrero, Puebla, Sinaloa, Nayarit, Michoacán, Tlaxcala, Mexico, Morelos and Tamaulipas. In size, it ranks eighth among the 25 hotspots; yet in terms of biodiversity, it heads the global list along with the Tropical Andes and Sundaland.

The very high biodiversity of this region is in part attributable to its geographic position at the junction of two of the world's great biogeographic realms - the Nearctic of North America and the Neotropical of South and Central America and the Caribbean - and its role as a land bridge between the continents. It was only about 5 million years ago (very recently in geological time) that parts of Central America rose above sea level, creating a land bridge between North and South America. For the first time, South American monkeys and sloths met North American squirrels and raccoons in the forests of Central America. Aided by the diverse topography of the land bridge - including ancient crystalline uplands, younger metamorphic mountain ranges, and active volcanoes - the region developed its own unique species, resulting in high faunal and floral endemism in the transition zone itself.

Levels of Biological Diversity and Endemism

This hotspot has an estimated 24,000 species of vascular plants, of which approximately 5,000 (21%) are endemic. The figure for total diversity is fourth highest, exceeded only by the Tropical Andes, Sundaland and Mediterranean hotspots, while the figure for endemism ranks 10th on the global list. Vertebrate diversity is even more impressive. Mammal diversity is the second highest on the hotspot list, with 521 mammal species (195 species of rodents alone), exceeded only by the Guinean Forests of West Africa. Of these, 210 (a remarkable 40%) are endemic, surpassing by 50 the number of endemic mammal species in any other hotspot. Resident bird species number 1,052 and migrant species 141, for a total of 1,193, second only to the Tropical Andes. Of these, 251 (21%) are endemic, again exceeded only by the Tropical Andes. Not surprisingly, this region is also a top priority for BirdLife International, which recognizes no fewer than 17 Endemic Bird Areas within the hotspot, covering almost its entire extent; this figure also is exceeded only by the Tropical Andes. The region is a critical flyway for at least 225 migratory species; three of the Western Hemisphere's four migratory bird routes converge in Mesoamerica.

This region is ecologically complex and has been organized and subdivided according to many different scientific approaches. The World Life Zone System of Ecological Classification has been widely used in Mesoamerica; the entire region except for parts of Mexico and eastern Nicaragua has been mapped using this approach. In the Mesoamerica Hotspot, 30 of these life zones have been mapped - 25% of all life zones known to exist on the planet. Fifteen of these occur in the tropical latitudes, extending from Panama into a few spots in southern Honduras and El Salvador, and ranging from Tropical Basal Dry Forest, Tropical Basal Moist Forest, and Tropical Basal Wet Forest up to Tropical Subalpine Rain Páramo. The other 15 occur in the subtropical latitudes, extending from central Nicaragua north into Mexico and ranging from Subtropical Basal Dry Forest, Moist Forest and Wet Forest up to Subtropical Nival, found on some Mexican volcanoes with permanent snowfields.

The Caribbean lowlands harbor significant moist, wet forest and rainforest life zones in both the subtropical and tropical latitudes. Subtropical wet and rain forests exhibit very high species diversity and are well represented in this hotspot by La Selva Lacandona in southern Mexico, the Toledo District of Belize, the La Mosquita region of Honduras, Nicaragua's Costa de Miskitos, and the Sarapiquí and Tortuguero Plains of northeastern Costa Rica. Pine savannas occur on exceptionally poor sandy soils in northeastern Nicaragua in particular and are dominated by the Caribbean pine and oak.

Prioritization of Corridors within the Hotspot

The entire Mesoamerica hotspot represents a global conservation priority; however, the region's size and international scope, and the limited funding available, necessitate further prioritization of corridors within the hotspot to achieve the greatest impact. The southern region of the Mesoamerica Corridor harbors the highest mountain forests in Central America, with the most extensive and best-protected cloud forests in the region. The design and implementation of conservation initiatives in these corridors is the first step toward preservation of species and ecosystem diversity throughout the hotspot.

Factors in selection of these target corridors for CEPF investment included:

• need to focus limited resources for greater impact;
• desire to capitalize upon Conservation International's existing program based in Costa Rica to achieve economies of scale for managing CEPF in the region;
• desire to support existing conservation priority-setting processes;
• goal of strengthening existing NGO partnerships;
• opportunities to support existing priority corridors of the MBC; and
• potential to connect adjacent protected areas with a binational focus, such as those between southern Nicaragua and Costa Rica and between Costa Rica and Panama.

The argument for focusing on the southern region of Mesoamerica and particularly for these three specific corridors was also driven by a scientific assessment showing that this region holds at least 37 Threatened terrestrial vertebrate species. Of these, 25 are endemic to the southern region, and 28 are endemic to Mesoamerica (half of Mesoamerica's threatened endemics). The 25 species are concentrated in three areas: the mountains of northern Costa Rica; the Pacific slope of southeast Costa Rica, including the Osa Peninsula; and the Atlantic slope of the mountains of eastern Costa Rica and western Panama, including Isla Escuda de Veraguon. In addition, these three areas hold 12 Threatened species with wider range. Only three of the region's Threatened species are not represented within the corridors.

These biological considerations, coupled with the need to maximize return on limited investment, resulted in the decision to focus CEPF investment on the southern region of the Mesoamerica hotspot, and specifically on three priority areas: the Rio San Juan-La Selva corridor between Nicaragua and Costa Rica; the southern Talamanca region connecting with the Osa Peninsula; and the northern Talamanca-Bocas del Toro corridor. Concentrating CEPF investment in these corridors is a logical first step for a phased approach to CEPF involvement in Mesoamerica. Therefore, the CEPF's approach in Mesoamerica will be implemented in distinct phases concentrating on Southern Mesoamerica first and Northern Mesoamerica within the next three years.

The northern region of Mesoamerica possesses critical conservation targets within the hotspot. Extending from the southern states of Mexico to the borders of Guatemala, Honduras, and El Salvador, ongoing prioritization processes have identified three key conservation areas: the Zoque Forest of Oaxaca, including the Chimalapas region; the Quetzal Corridor linking El Triunfo Biosphere Reserve with the western highlands of Guatemala; and the Selva Maya region of Guatemala, Mexico, and Belize. In Selva Maya, an alliance of NGOs called the Selva Maya Coalition is beginning to unite efforts and develop a joint strategy to protect this vast tropical forest region spanning three national borders.

The CEPF's focus on the south reflects the need to address the critical conservation requirements of both regions separately. The CEPF management team hopes to secure authority from the Donor Council to emphasize the northern region of Mesoamerica in a different cycle of preparation and future grantmaking. This Ecosystem Profile presents both an overview of the broader Mesoamerica perspective and data specific to the three priority corridors in Nicaragua, Costa Rica, and Panama.

Given that all three CEPF priorities in Southern Mesoamerica have received significant multilateral funding, CEPF will favor projects that demonstrate longer-term financial sustainability. Project proposals demonstrating a binational focus will be reviewed more favorably. The three distinct regions of South Mesoamerica will be eligible for the following distribution of resources:

Cerro Silva-Indio Maiz-La Selva Corridor

This expansive area in southeast Nicaragua and the northern Costa Rica (La Selva) region spans more than 840,000 hectares, and consists of coastal, wetland, and tropical forest ecosystems. Beginning at the Rio Grande de Matagalpa and Cerro Wawashan in the north and extending south to Costa Rica and west to Lake Nicaragua, the region includes the Los Guatuzos and San Miguelito wetlands and the Solentiname archipelago of Lake Nicaragua, and represents one of the most untouched areas of Mesoamerica.

Talamanca-Osa Corridor

This corridor spans more than 100,000 hectares and links the southern Pacific coast of Costa Rica with the expansive Talamanca mountain range. It includes the Osa Peninsula and the Piedras Blancas National Park.

Talamanca-Bocas del Toro Corridor

Including the La Amistad Biosphere Reserve, this region of more than one million hectares connects the Talamanca mountain range with the Caribbean coastline and wetlands of northwestern Panama. This area includes the Ngobe indigenous territory.

Status of Protected Areas in Mesoamerica

Although many Mesoamerican countries declared protected areas in the 1950s and 1960s for recreation or outstanding archeological monuments, new protected areas were not established until the mid-1970s following the of rapid natural resource deterioration. Currently, the Central American System of Protected Areas (SICAP) includes 411 declared and 391 proposed protected areas, covering 9.5 million hectares or 19% of the region. Of these, 70 are national parks (3.6 million hectares); 45 are biological reserves (460,000 hectares); 43 are forest reserves (1.4 million hectares); 71 are wildlife refuges (490,000 hectares); 32 are special protection zones (310,000 hectares); 37 are archeological areas; 12 are recreation areas; 15 are wetlands; and six biosphere reserves. The region includes at least 37 Ramsar sites and seven World Heritage sites.

Costa Rica leads the region in protected areas as a percentage of total land, with 132 protected areas covering 12,295 square kilometers (24% of the country's land). Guatemala is next, with 34 protected areas covering 24,564 square kilometers (23%); Nicaragua has 73 protected areas covering 21,888 square kilometers (17%); Panama has 12,957 square kilometers of protected areas within the hotspot (29% of the Mesoamerica Hotspot portion of Panama and 17% of the country as a whole); Belize has 14 protected areas covering 2,397 square kilometers (10%); Honduras has 8,636 square kilometers (8%); and El Salvador has so little habitat left that only 52 square kilometers are protected, representing less than 3% of the country.

It is important to note that two-thirds of these areas each protect less than 10,000 hectares; only 38 areas protect more than 50,000 hectares. About half of these protected areas have prepared management plans - generally with minimal funding for implementation - and it is estimated that about one-third of have no on-the-ground institutional presence within them. Costa Rica's protected areas are notable for the size and technical capacities of their personnel, but across the region few protected areas have adequate staff and most managers are insufficiently trained. More than 23 distinct ethnic groups live within the region's protected area system. Tourism brings approximately 1 million visitors per year to these protected areas, especially in Costa Rica.

While these numbers may seem low, it should be noted that in 1987, there were only 220 protected areas in the region, covering only 10.8% of the land. The progress made in the 1990s should be recognized; yet it is essential to reinforce the protection of those areas already declared. An overview of the protected areas in this ecosystem profile's area of focus is shown in Table 1.

The full list of protected areas in the ecosystem profile's area of focus is in Table 2.

The movement for private protected areas is growing rapidly in Mesoamerica, especially in Costa Rica. The Costa Rican Association of Private Protected Areas has registered more than 81 private protected areas, and similar groups are just getting started in Nicaragua and Panama.

All seven Central American nations have ratified the Central American Biodiversity Treaty, and in 1997 all Central American presidents agreed to support the Central American Protected Areas System and the Mesoamerican Biological Corridor. This example of regional cooperation was reaffirmed in March 2001, and reflects a strong commitment to environmental problem-solving at the regional level.

 

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