Tropical Ecology and Conservation [Monteverde Institute]

Alternative Title

Las concentraciones de azúcar, la agresividad en el colibrí, y la composición de la comunidad en Monteverde, Costa Rica



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Publication Date

August 2006


We studied hummingbird communities in Cañitas, Monteverde, Puntarenas, Costa Rica to observe territorial tendencies when given high and low percentage sugar concentration of food resources at artificial feeders along the edge of a forest patch. We wanted to determine if community composition was disproportionately affected by more aggressive, and therefore territorial species. We observed interactions of hummingbirds at artificial feeders of 20 and 33% sugar concentration. We found a disproportionately high number of visits by Rufous-tailed Hummingbirds (Amazilia tzacatl) at both sets of feeders (52.5% at 20% feeders and 89.4% at 33% feeders). We found a higher frequency of visits by all species at low reward feeder than at the high reward feeder (1016 visits at 20% feeders and 716 at 33% feeders) and a higher proportion of aggressive interactions at the lower reward feeder. Rufous-tailed hummingbirds were the most territorial species at our study site and their behavior influenced the relative abundance of subordinate species. Contrary to what we expected, we found that frequency of close chases and far chases at different sugar concentration feeders were not different than random.


Estudiamos las comunidades de colibríes en Cañitas, Monteverde, Puntarenas, Costa Rica para observar las tendencias territoriales cuando se les dio concentraciones de recursos alimenticios en comederos artificiales a lo largo del borde de un parche de bosque. Queriamos determinar si la composición de la comunidad estaba desproporcionadamente afectada por especies mas agresivas, y por lo tanto territoriales.


Hummingbirds, Species diversity, CIEE Summer 2006

Palabras claves

Colibríes, Diversidad de especies, CIEE Verano 2006


8 pages

Geographic Location

Cañitas (Guanacaste, Costa Rica)

Holding Location

Monteverde Institute


English; Spanish

Media Type



Digital Only





Sugar concentrations, hummingbird aggressiveness, and community composition in Monteverde, Costa Rica, August 2006



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