FIELD GUIDE Terrain and Flora
Terrain and Flora
Few countries on earth can rival Costa Rica for biodiversity. Despite its tiny size, the nation is home to almost 5 percent of the world’s identified living species, including an estimated 1,200 types of butterflies. This astonishing wealth of wildlife is due to the country’s great variety in relief and climate, from lowland wetlands to cloud-draped mountains. As a result, Costa Rica has several distinct “life zones,” each with a unique combination of climate, terrain, flora, and fauna.
Lowland Rainforest
Tropical rainforests cloak many of the plains and lower mountain slopes of the Caribbean lowlands and Pacific southwest, its canopies forming an uninterrupted sea of greenery. These complex ecosystems harbor much of the country’s wildlife. Hardwood trees, such as mahogany and kapok, may tower 200 ft (61 m) or more, and rely on widespreading roots to support their weight. These forests comprise distinct layers, from ground to treetop canopy. Each layer has its own distinct microclimate as well as flora and fauna, with the vast majority of species concentrated at higher levels. Tapirs and jaguars inhabit the ground level, while birds and monkeys cavort in the treetops. Animals such as kinkajous, sloths, and arboreal snakes are also adapted for life in the branches, which are weighed down by vines, epiphytes, and other vascular plants.
Montane and Cloud Forests
Named for the ephemeral mists that envelop them, Costa Rica’s cloud forests are typically found at elevations of 3,300 ft (1,000 m) above sea level, which accounts for more than half of Costa Rica’s terrain. These areas show extreme local variations in flora. On wind-swept exposed ridges, trees and shrubs grow closer to the ground, forming forests with a primeval quality. Protected areas have taller vegetation with several levels, although the lush canopies rarely reach 100 ft (30 m). Epiphytic plants such as orchids and bromeliads cling to branches, which also drip with lichen, fungi, mosses, and liverworts. The interplay of sunshine, clouds, and rainfall produces flora of astounding diversity. Fauna is correspondingly abundant, although the mists and thick foliage hamper sightings.
Páramo
Páramo ecosystems, a mix of grassland and scrubland, are found in small regions above the forest line. These arid treeless uplands are a populated by tenacious species of rodents, lizards, and snakes, and are valuable hotspots for observing the processes of evolution.
Dry Deciduous Forest
Once covering most of Guanacaste and Nicoya, dry forests today cover only about 200 sq miles (520 sq km) of Costa Rica. The mostly deciduous flora sheds its leaves during seasonal droughts, making wildlife easier to spot. Conservationists are trying to revive dry forest ecosystems.
Wetlands and Mangroves
Wetlands range from coastal mangroves, such as the Terraba-Sierpe delta in the Pacific southwest, to inland lagoons, such as Caño Negro in the north. Many habitats are seasonal, flooding in the wet season from May to November; wildlife gathers in the December–April dry season. Mangroves thrive in alluvial silts deposited by rivers, forming a vital coastal nursery for marine creatures, such as the olive ridley turtle, and avian fauna, such as the frigate bird.
Marine Environments
Costa Rica’s coastline stretches over 800 miles (1,290 km). Promontories and scalloped bays are common on the Pacific side, while the Caribbean coast is almost ruler straight. Small patches of coral reef fringe the coast off the central Pacific and southern Caribbean shores. Many beaches, notably Tortuguero on the northern Caribbean coast, provide nesting grounds for turtles. Bahía Ballena (“Whale Bay”) on the southern Pacific side is a famous birthing ground for colossal humpback whales (and coincidentally features a sandbar shaped exactly like a whale’s tail).
FIELD GUIDE Terrain and Flora
t Rocky marine environments at low tide.