The objective of this study was to determine the birdspecies in the Yuvacik Dam watershed in the province of Kocaeli, The total area of the study site was 25800 ha, and was subdivided to 60 plots (the size of each plot, 2x2 km). Observations and inventory for each species were carried out. A total of 130 species belonging to 38 genus of 16 orders were identified. Eighty-seven were classified as Passeriformes. Forty two species breed in the region. A total of 21223 birds were counted. According to IUCN criteria, two species, (Ficedula semitorquata (Von H., 1885) and Sitta krueperi (Pelzeln, 1863), were categorized as near threatened (NT).