176 
Psyche 
[Vol. 88 
Fig. 1. The ravine forest at Cuesta Angel, near Cariblanco, Heredia Province, 
Costa Rica. 
Methods 
The Cuesta Angel ravine is an extensive strip of very steep 
primary and river-bottom forest (Fig. 1) filtering down from the 
highest mountains of Costa Rica’s Cordillera Central and tapering 
into the northeastern lowlands known as Sarapiqui. Because of its 
rugged profile much of the ravine remains blanketed in forest even 
though surrounding level areas have been largely converted to 
pastures. This ravine is within the recently extended Carillo Nation- 
al Park. There have been relatively few field studies of plants and 
animals in the ravine, even though both its invertebrate and 
vertebrate faunas contain many forms not found in other parts of 
Costa Rica. “Cuesta Angel” is located about 10 km south of the 
village of Cariblanco (10° 16'N, 84° 10'W), Heredia Province, and is 
classified as montane tropical wet forest (elev. about 1200 m) 
(Holdridge 1967). The vertical drop in the ravine is about 300 m. 
