Spatial distribution of birds under the influence of the tides in a mud bank area in the estuary of Cananéia, state of São Paulo, southeastern Brazil

The spatial distribution of individuals in a community is defined by environmental, morphological and ecological issues. In the case of estuarine bird species, the morphology directly influences the foraging and, consequently, the degree of dependence of the tidal regime. Aiming to study the dynamics of a community of birds in a mud bank (Baixio do Brocuanha) located in the City of Cananéia, south coast of the State of São Paulo, southeastern Brazil, we evaluated the spatial and temporal distribution of the species under the influence of the tide. For this, observations from a fixed point were made, counting of individuals of each species at set intervals and plotting points to estimate the location of each individual. Graphs of the mud bank’s occupation dynamics and maps of spatial-temporal distribution were made based on the analysis of the collected data. From the thirty species using the Baixio do Brocuanha, Ardea alba (Linnaeus, 1758) was always the first to occupy the area and the last one to leave. The species widely distributed in the mud bank were Eudocimus ruber (Linnaeus, 1758) and Egretta caerulea (Linnaeus, 1758). Platalea ajaja (Linnaeus, 1758), Egretta thula (Molina, 1782), Ardea alba (Linnaeus, 1758) and A. cocoi (Linnaeus, 1766) were restricted to a smaller sectors of the mud bank near the water bodies. Finally, we highlight the diversity of species recorded in the area as well as the relevance of the Baixio do Brocuanha as a feeding site for resident and migratory bird species.