Iran possesses a very rich and divers bird fauna, despite the fact that large portion of the country are arid to semi-arid; 491 species have been recorded.
Tow main factors are responsible for this; the great range of habitats-from permanent snows to deep deserts and from lush deciduous forest in the north to palm groves and mangrove in the south – and Iran's position at a crossroads between three major faunal regions. The bulk of the country lies within the Palearctic realm. Lying along the southern edge of this region .
Iran's bird fauna includes a large western Pale arctic faunal element, reaching its eastern extremity in the central Alborz and Zagros mountains, and a smaller, which extends into north-east Iran in the highlands of Khorasan. In southern Iran, two other faunal regions have a pronounced influence on the avifauna: the Indo-Malayan realm in the south-west.
Of 324 breeding species,131 occur widely in the Palearctic region. Eightyone are western Palearctic species, reaching the easternmost extremities of their ranges in Iran, while 19 are typically eastern Palearctic species, reaching the westernmost tip of their ranges in Iran . a further 25 species are characteristic of the great Saharo-Sindian desert belt which stretches along the southern adage of the Palearctic region from North Africa through the Middle East to Mongolia, while another 24 are Palearctic species with restricted ranges in the Middle east.

The bird fauna of southern Iranian Baluchistain and the southern Persian Gulf coast is predominantly Indo-Malayan, origin reaching the north-west Iran there is a small Afrotropical
influence with six breeding species of African origin. Finally, there are nine species of seabird and shorebird of the Indian Ocean, which breed on islands in the Persian Gulf and the Strait of Hormoz...