Tropical Ecology and Conservation [Monteverde Institute]

Alternative Title

Agresión en la interacción del color y la preferencia de la concentración de azúcar en los colibríes (Trochilidae) del bosque nuboso de Monteverde



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Publication Date

November 2008


In Monteverde, Costa Rica, a number of hummingbird species coexist that are extremely important for pollination. Hummingbirds may prefer flowers of a certain color because they associate it with a higher nectar reward. They also may be territorial and defend especially rich food sources, dominant birds driving away all subordinates. The purpose of this study was to investigate color and sugar concentration preference in hummingbirds using artificial feeders, and to determine whether dominance and aggression has an effect on food choice. Many hummingbird-pollinated flowers are red, so I hypothesized that all species would show a preference, and predicted that all would initially choose the red feeder of highest sugar concentration, eventually also choosing the two other high concentration feeders, realizing their equal reward. I also predicted that larger, male hummingbirds would dominate the food source more territorial, dominating the food source and forcing smaller birds to choose their second choice feeder. This was done by hanging six feeders of red, yellow and purple and high and low sugar concentration and recording species preference. I found that the Violet Sabrewing was the species that most often chose the red, high concentration feeder, as predicted (p=0.041669, df=2, x2= 6.356). No conclusions could be made about the three other species investigated as results were not significant. Preference was seen in the Violet Sabrewing, as differences in feeder preference decreased when only the last four days of data were analyzed, suggesting that color preference decreased. Most aggression was observed from the Violet Sabrewing (p=0.006019, df=9, x2=23.08). This species was clearly dominant likely due to its large size. El propósito de este estudio fue investigar el color y la preferencia de la concentración de azúcar en colibríes usando comederos artificiales, y determinar si la dominancia y la agresión tienen un efecto en la elección de alimentos.


Hummingbirds, Colibries, Monteverde Cloud Forest Reserve (Costa Rica), Reserva Biologica Bosque Nuboso Monteverde (Costa Rica), CIEE Fall 2008, CIEE Otoño 2008


Student affiliation : Department of Biology, Western Washington University Born Digital

Subject: topical

Hummingbirds; Colibries; CIEE Fall 2008; CIEE Otoño 2008

Subject: geographic

Monteverde Cloud Forest Reserve (Costa Rica); Reserva Biologica Bosque Nuboso Monteverde (Costa Rica)



Holding Location

Monteverde Institute MVI



Interaction of color and sugar concentration preference with aggression in Monteverde Cloud Forest hummingbirds (Trochilidae)



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