Seasonality in the Brazilian Pantanal influences avian functional diversity

ABSTRACT

Seasonality significantly affects environmental changes in the Pantanal, especially during wet and dry periods. Inundation and drought impact the onset of flowering and fruiting and the occurrence of insects. Because such resources may vary across seasons, it is expected that avian functional diversity also changes. We examine how functional diversity changed over time, as measured by functional richness and functional divergence. For functional richness, we observed a functionally overdispersed bird community over the seasons, whereas for functional divergence, two different patterns were found: (1) functionally overdispersed bird communities during the wet and receding seasons and (2) functionally clustered avian communities in the dry and rising seasons. The diversity of functional groups did not significantly vary across the seasons, as expected, but varied between forests and savannas. The environment has restricted resources in certain seasons, benefiting species with specific functional characteristics, however, bird species in the Pantanal are often generalists adapted to using a wide variety of food resources. Although the habitat turnover rate is an important factor that influences bird species composition across seasons, the changes in species composition still allowed the maintenance of certain functional characteristics, contributing to conservation of the existing functional groups in the ecosystem.

KEYWORDS:

• Functional richness
• functional divergence
• seasonality
• savanna
• forest

Acknowledgments

We greatly appreciate the financial support from the following institutions: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brasil; Instituto Nacional de Ciência e Tecnologia em Áreas Úmidas (INAU/UFMT/CNPq/INCT); Centro de Pesquisa do Pantanal (CPP); and the Brehm Funds for International Bird Conservation (BF), Germany. Furthermore, we thank the SESC Pantanal administration for permission to conduct research on their property and for their logistical help with our fieldwork, and Dr. Ana Silvia Tissiani for her technical support to prepare the figures.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

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Additional information

Funding

This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; Brehm Funds for International Bird Conservation; Instituto Nacional de Ciência e Tecnologia em Áreas Úmidas.