A 55-km stretch of the Dez river, several associated oxbow lakes, and the adjacent marshy plains of Deh Noh and Ahu Dasht (8,000 ha of wetlands), c.35-90 km north of Ahwaz. The river forms a deep channel with steep earth banks. Dense riparian forest (Tamarix and Populus euphraticus) up to several hundred metres wide lines the river and surrounds the lakes which also have some Phragmites beds. The adjacent plains, largely under wheat and other crops, are dotted with shallow marshy depressions and meandering creeks which flood in winter.
See boxes for key species. The wetlands are very important for wintering surface-feeding ducks, geese (including Anser erythropus), Pelecanus crispus and Threskiornis aethiopicus. This stretch of river is the only known haunt of Anhinga rufa in Iran while the reeds around the oxbow lakes form one of the very few sites in Iran where Turdoides altirostris is known. The riverine thickets support a typical Mesopotamian bird fauna, with large breeding populations of Hypocolius ampelinus and Passer moabiticus, but also several species (e.g. Columba palumbus, Turdus merula, Parus major) more typical of Zagros oak forest. Other notable species include Eudromias morinellus, Ceryle rudis, Halcyon smyrnensis and Petronia xanthocollis. At least 133 species have been recorded in the area.
Non-bird biodiversity: Mammals: a few tens of Dama mesopotamica (E) still survive in the forest along the river; this is the only known truly wild population in the world. Other species include Gazella subgutturosa (rare).
BirdLife International (2021) Important Bird Areas factsheet: Dez river marshes and plains. Downloaded from http://www.birdlife.org on 25/01/2021.