The Passer is a small bird species. On the territory of Bulgaria there are 4 species – the sparrow is the most widespread, and in the villages and in the countryside there are the Polish sparrow, the sparrow rocky and the relatively new species with a low number – the Spanish sparrow.
They feed mainly on plant food, insects and other small invertebrates, feeding their little ones primarily with animal food. Their bead is fitted with a strong musculature and a scissor-fastening edge at the base, making it especially suited for shredding hard seeds. The nests are rounded with a lateral hole, can be found in tree branches or in holes.