Ecological Gradients Influencing Waterbird Communities in Black Water Lakes in the Anavilhanas Archipelago, Central Amazonia

Renato Cintra

doi:10.1155/2012/801683

Abstract

For the first time, and in a large spatial scale, the influence of ecological properties on the aquatic bird community of black water lakes in Brazilian Amazonia is evaluated. Bird surveys were conducted in 45 lakes. A total of 3626 individuals in 48 bird species were recorded; of these, 31 are aquatic, and 18 of these are primarily piscivorous. Bird richness and abundance were not significantly related to lake shape and productivity but were influenced by hydrological period (low versus high), water depth, transparency, lake isolation, and habitat richness. Matrices of bird species by lake were subjected to multivariate analyses (NMDS) to evaluate how these parameters influence bird community. The variation in bird species composition was positively correlated to lake depth and isolation and negatively correlated to water transparency and habitat richness. The results indicate that period, lake physical characteristics (depth, water transparency), isolation, and habitat richness are determinants of aquatic bird community composition in the black water lake systems of Amazonia.

Highlights

IntroductionTropical wetlands provide habitats for a wide variety of plants, fishes, birds, and mammals
Ecological studies on the composition and structure of biological communities are critical to understanding the interactions between the species and populations that comprise them, to explain local and regional biodiversity [1, 2], and are essential to guiding management actions and conservation policies.Tropical wetlands provide habitats for a wide variety of plants, fishes, birds, and mammals
Bird surveys were conducted on the black water lakes of Anavilhanas Archipelago, state of Amazonas, Brazil (Figures 1 and 2, 2◦3 S and 3◦2 S, 60◦22 W, and 61◦12 W), a National Park administered by Instituto Chico Mendes (ICMBio-MMA, Brazil), located 40 km northwest of Manaus, the Amazonas state capital

Summary

Introduction

Tropical wetlands provide habitats for a wide variety of plants, fishes, birds, and mammals. Aquatic environments (rivers, lakes, and wetlands) represent 6% of Brazilian Amazonia, and over 100,000 km of lakes and swamps [3]. Aquatic birds are ubiquitous components of Amazonian freshwater systems. Their role in the ecological dynamics of these systems has often been overlooked, as in other rainforest areas in the Neotropics (but see [4,5,6]). In order to evaluate the impacts of human activities on freshwater systems and improve their conservation value, the status and trends of freshwater biodiversity need to be monitored [7]

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Results

Conclusion