Berkeley Scientific Journal

Habitat fragmentation is currently the greatest threat to the avifauna of Costa Rica. To study its effects on bird species composition in the Monteverde region, I surveyed three sites of varying degrees of fragmentation. I did not detect a significant difference in the species richness and heterogeneity among the three sites. My study showed, however, that the species composition changed drastically among sites. Furthermore, the predominant feeding guilds of the species unique to each site changed between sites, suggesting that food availability is an important determinant of where a bird lives. The proportion of insectivores was inversely related to fragmentation, and omnivores are perhaps less affected by fragmentation than other feeding guilds because they are able to use a higher variety of food resources. Certain species were only found at the more continuous sites, including the Black-breasted Wood-quail (Odontophorus leucolaemus), which implies they may be more sensitive to habitat fragmentation.