Distribution patterns and community composition of waterbirds in wetlands in the state of Rio de Janeiro
Bird, Community structure, Spatial and temporal variation, Continental aquatic environments
Understanding how communities vary in space and time concerning environmental conditions
and abiotic factors is essential to promote waterbird conservation, either in natural or human-
altered areas. This work aimed to verify the effects of environmental heterogeneity and spatial,
temporal, and weather variation on the distribution and composition of waterbird communities
in continental wetlands. The community structure of waterbirds differed between lakes of
artificial, natural, and temporary origin. Richness and abundance increased with increasing lake
area and distance from human settlement; however, they decreased with increasing depth and
extension of open surroundings. Abundance was also influenced by pH, increasing in sites with
less acidic pH, and semi-shaded surroundings and grazing pressure, decreasing the number of
individuals with the increase of these two variables. The environmental variables with the
greatest contribution to the distribution of guilds were the lake area, pH, semi-shaded
surroundings, distance from human settlement, macrophyte, and aquatic vegetation height. On
the temporal scale, richness remained relatively stable, however, abundance increased over
time. Temporal trends were also identified in species composition and dispersion patterns.
Precipitation and temperature did not influence richness, indicating that the high number of
resident species contributed to a relatively constant richness over time. However, variation in
species abundance was inversely related to precipitation and temperature levels, which also
influenced environmental conditions acting on the availability of resources and foraging sites
for waterbirds. The results suggest that aspects of community structure, richness, abundance,
and guilds, are uncoupled and respond in an independent and shared way to the effects of
environmental and anthropic variables in inland lakes. Therefore, these aspects must be
considered in a common framework when analyzing changes in the structure of waterbird
communities.