Dinámica temporal y espacial de una comunidad de aves en un gradiente altitudinal de la Cordillera Volcánica Central de Costa Rica, vertiente Caribe

Abstract

Conservation and management of biodiversity requires an accurate assessment of the dynamics and number of species in a given community. Between 2004 and 2009, bird richness was estimated along the Volcán Barva- La Selva transect on the Caribbean slope of the Cordillera Volcánica Central of Costa Rica at 100, 200, 400 and 500 m elevation. Species richness was compared between 100m and 500m and the probability that species from one altitude occurred at another was also estimated. The highest richness values were found at 500 m. The probability that a species that occurs at 100 m also occurs at 500 m was 92% (95% CI: 78.56% - 100%) and the probability that a species found at 500 m also occurs at 100 m was 68% (95% CI: 56.35% - 82.53%). Additionally, the richness and probabilities of local extinction and local colonization were estimated for the years 2005, 2006, 2007, and 2008. The community presented a trend towards increased annual richness with the highest point in 2007 followed by a decrease in 2008. During the period 2005-2008 the community experienced dynamic equilibrium with a higher proportion of local extinctions (local extinction rate of 7%) compared to local colonizations (local colonization rate of 5%).Entry and exit of latitudinal migratory species altered this tendency. A greater representation of trophic groups of birds is expected at 500 m elevation; however, the ecological integrity of the gradient should be maintained to preserve the community of birds.