The width and biotic integrity of riparian forests affect richness, abundance, and composition of bird communities

Abstract

In riparian forests, width contributes most importantly to maximizing diversity. Therefore, corridors with different widths should differ in richness, abundance, and composition. We tested this hypothesis for the bird communities of two forests on the Upper Paraná River floodplain, Paraná, Brazil. Richness and abundance were higher in riparian forest with mean width of 50 m in each margin and lower anthropogenic disturbance. Species diversity increased 30%, with increase in total width from 40 m to 100 m on average. Bird species composition also differed, and groups with the strictest ecological requirements were better represented in the wider, better-preserved forest. This indicates that conservation of riparian forests has a positive effect on their bird communities. We suggest that these environments are prioritized for recuperation, and that a 50 m width on each side of a stream is necessary for riparian forests to effectively fulfill their function in the landscape. We also note that the recently discussed Brazilian Forest Code does not conform to this requirement. © 2014 Associação Brasileira de Ciência Ecológica e Conservação. Published by Elsevier Editora Ltda.