Water-level controlled reservoir as refugia for waterbirds in an urban landscape

Abstract

Artificial wetlands can play an important role in waterbird conservation due to habitat loss and degradation of natural wetlands. Urban reservoirs can harbor waterbird communities, but they usually have lower biological diversity than natural wetlands. However, the value of reservoirs for waterbird conservation in urban areas needs further exploration. Here, we surveyed the waterbird community in a water-level controlled reservoir of an urban area in southeastern Brazil. We evaluate the seasonal variation in species composition, richness, and abundance. Monthly samplings were carried out between July 2017 and February 2018, through a boat line transect. A total of 7762 waterbirds were recorded, belonging to 32 species and 16 families. There were significant differences in species composition and abundance between dry and rainy seasons. The community was dominated by generalist and resident species, which Gallinula galeata and Jacana jacana were the most abundant species. We did not register migratory shorebirds during the surveys. Our results highlight the importance of reservoirs in urban areas, as they harbor feeding areas and breeding sites and may serve as refuges during dry seasons for resident waterbirds. We suggest management strategies to improve the importance of water-level controlled reservoirs as breeding areas for resident species and migratory stopover for shorebirds. Our results may also be considered for urban planning and waterbird conservation in urban areas.