Floral resources and habitat affect the composition of hummingbirds at the local scale in tropical mountaintops.

Lc Rodrigues,M Rodrigues

doi:10.1590/1519-6984.06913

Abstract

Hummingbird communities tend to respond to variation in resources, having a positive relationship between abundance and diversity of food resources and the abundance and/or diversity of hummingbirds. Here we examined the influence of floral resource availability, as well as seasonality and type of habitat on the composition of hummingbird species. The study was carried out in two habitats of eastern Brazilian mountaintops. A gradient representative of the structure of hummingbird community, based on species composition, was obtained by the ordination of samples using the method of non-metric multidimensional scaling. The composition of hummingbird species was influenced by the type of habitat and floral resource availability, but not by seasonality. Hummingbird communities differ between habitats mainly due to the relative abundance of hummingbird species. The variation in composition of hummingbird species with the variation in floral resource availability may be related to differences in feeding habits of hummingbirds. Hummingbird species with the longest bills visited higher proportions of ornithophilous species, while hummingbirds with shorter bills visited higher proportions of non-ornithophilous species. The results demonstrate that at local-scale the composition of hummingbird species is affected by the type of habitat and floral resources availability, but not by seasonality.

Highlights

In bird communities the species richness and abundance of individuals may vary spatially and temporally (Malizia, 2001) due to population processes and individual movements within and between habitats (Loiselle and Blake, 1991; Poulin et al, 1993)
We describe the seasonal variation of the hummingbird species richness and composition in two different habitats (‘typical campos rupestres’ or open rocky fields, and ‘capões de mata’ or forest patches) and its correlation to floral energetic resources
With the exception of male and female of A. scutatus (Figure 2A and B) and Campylopterus largipennis (Boddaert, 1783) (Figure 2C), which were more frequently captured in the open rocky fields, the other hummingbirds were more frequently observed in the forest patches or had similar frequencies between the sampled habitats (Figure 1)

Summary

Introduction

In bird communities the species richness and abundance of individuals may vary spatially and temporally (Malizia, 2001) due to population processes (births and deaths) and individual movements within and between habitats (Loiselle and Blake, 1991; Poulin et al, 1993). The main reasons for movement are related to variation in resource availability, habitat structure, climates conditions and competition The capture rates of frugivorous birds have been positively correlated with fruit availability (Loiselle and Blake, 1991)

Objectives

Methods

Results

Conclusion