Lying c.45 km west-south-west of Hamadan, the site is a shallow basin 21 km long by up to 12-14 km wide, almost completely surrounded by a ring of hills 1,800-2,100 m high. The central area remains grassland, but is heavily grazed by domestic livestock and Euphorbia is common, while the gently sloping perimeter is cultivated with cereals. The small towns of Assadabad and Kharkiz are situated on the northern margin, and there are about nine small villages scattered across the plain. The main Hamadan to Kermanshah road crosses the eastern edge of the plain. The surrounding hills are Artemisia steppe. The plain is relatively densely populated. Land ownership is private.
See box for key species. The best breeding area for Otis tarda in western Iran in the 1970s. Birds were present March-September, and it was believed that c.20 females were nesting; up to 30 birds (8 males, 22 females) were recorded in the early 1970s, but local farmers reported that numbers in autumn had been as high as 80-100 c.15 years previously. Winter visitors include Aquila chrysaetos and Accipiter nisus, and passage migrants include Aquila nipalensis, Circus pygargus and C. macrourus.
Non-bird biodiversity: None known to BirdLife International.
BirdLife International (2020) Important Bird Areas factsheet: Assadabad plain. Downloaded from http://www.birdlife.org on 27/09/2020.