LA SELVA-BRAULIO CARRILLO MAMMALS 



3 



humedo que circunda el complejo pronto se transformara en una isla aislada de bosque pro- 

 tejido. Asi, el area se volvera cada vez mas valiosa como refugio para muchas especies 

 que necesitan espacios grandes en que el habitat no ha sido perturbado. 



Costa Rica, with an area of 51,022 km^, is a small country, but one of almost 

 unparalleled biotic diversity. Within the country's borders there are more than 

 12,000 species of plants, including 1 ,200 species of orchids and 2,000 tree species. 

 Costa Rica has more than 1,200 species of butterflies, more than are known from 

 all of Africa. There are some 150 species of amphibians and more than 212 species 

 of reptiles. More than 850 species of birds have been found in Costa Rica; this repre- 

 sents 10% of the world's species and more than have been found in the United States 

 and Canada combined. The native mammal fauna consists of at least 200 species, 

 all of which still can be found within the country's borders. The human population 

 of Costa Rica numbered 2.7 million in 1988 and is increasing at a rate of 2.6% 

 annually. Predictably, man and nature have come into direct conflict in recent years. 



On his fourth and final voyage to the New World in 1502, Christopher Colum- 

 bus became the first European to land on what the Spanish later termed the "Rich 

 Coast," Costa Rica. At the time of the Spanish conquest in the early 1500's, primary 

 forests covered an estimated 49,000 km^ or 96% of the national territory. This 

 land cover consisted of tropical dry forest, tropical moist forest, tropical wet forest, 

 tropical premontane moist forest, tropical premontane wet forest, tropical premon- 

 tane rain forest, tropical lower montane moist forest, tropical lower montane wet 

 forest, tropical lower montane rain forest, tropical montane wet forest, and tropical 

 montane rain forest (Holdridge 1967; Hartshorn 1983). Remaining land cover may 

 have included tropical subalpine rain paramo and savannah. The extent of indigenous 

 deforestation is unknown, but has been considered minimal. This may not be true 

 however, as there is increasing evidence that rather dense populations of Indians 

 lived in the Atlantic lowlands. 



The primary settlers of the northern Caribbean lowlands of Costa Rica were 

 individual families of European descent, the "campesinos." Land was cleared by 

 individuals working with hand tools. Large tracts of intact forest remained in this 

 area as late as the early 1970's. In the late 1970's and early 1980's habitat destruc- 

 tion in this region occurred at a significantly higher rate. This was due in part to 

 increased human population densities and the availability of chain saws. However, 

 perhaps of greater effect were two economic factors: (1) the increased need for 

 and value of lumber as a building material within Costa Rica; and (2) the soaring 

 international market for beef combined with the discovery that African cattle (Zebu, 

 Bos indicus) would prosper in this region when the forest was cleared and introduced 

 grasses planted. 



By 1940, 15,000 km^ of the forested habitat of Costa Rica had been altered. 

 During the following 37 years, an additional 18,000 km^ was deforested (Sader 

 and Joyce 1988). Thus, more primary forest was destroyed between 1940 and 1977 

 than during the preceding 400 years (Oficina de Planificacion del Sector Agro- 

 pecuario 1979). By the 1960's, nearly 50% of the forest had been destroyed by 



