A very large, permanent, shallow, fresh to brackish lake, lying in the Seistan desert in extreme south-west Afghanistan at 500 m, and surrounded by vast Phragmites reedbeds. It derives its waters from the Khashrud river, which is dry in summer but in spring carries meltwater from the central highlands of Afghanistan; formerly the Helmand river was also important but since construction of Kajaki Dam this river has carried little water into the Puzak. The wetland has always been subject to wide fluctuations in size according to variations in rainfall and snowfall in the mountains. About a third of the swampland is in Iran but by far the most permanent wetland is in Afghanistan, where at least formerly the habitat probably never dried out completely, even in the driest years. The wetland is fringed by Tamarix scrub, and surrounding desert is dominated by Artemisia steppe. In the 1970s the human population was relatively small (a total of c.1,000 in several villages).
This is the most important wetland in Afghanistan and of major international importance, estimated to hold up to one million wildfowl in winter. A total of 357,000 birds was counted in January 1976 during an aerial survey organized jointly with the Iranian government: see box for key species. Other wintering species in the 1970s included Tadorna tadorna (211), Circus aeruginosus (51) and Porphyrio porphyrio. Little is known of breeding or passage species as most visits have been in mid-winter; former breeding species included Phoenicopterus ruber, Anser anser, Cygnus olor, Netta rufina (possibly), and currently may still include Picus squamatus flavirostris (although possibly now extinct in Seistan through destruction of trees), Caprimulgus mahrattensis (reported as common by Cumming 1905 but not found subsequently, even by Paludan in 1949) and C. aegyptiacus (probable).
Non-bird biodiversity: Mammals: Canis lupus (V) is said to be common. The entire Seistan area is a unique ecosystem, but is very poorly known.
BirdLife International (2020) Important Bird Areas factsheet: Hamun-i-Puzak. Downloaded from http://www.birdlife.org on 23/01/2020.