Results of mid-winter waterbird counts in Iran in the early 1970s

The mid-winter waterbird counts in Iran were initiated by the Department of theEnvironment in January 1967. The counts focused on pelicans, flamingos, swans, geese,ducks, cranes and coots, but some counts were also made of other species of waterbirds. By the early 1970s, the counts were sufficiently comprehensive to enable estimations to be made of the total numbers of many species of waterbirds present in Iran in the mid-winter period. The overall results of the counts and these population estimates are presented in a series of tables. It was estimated that in an ‘average’ year in the early 1970s, there were approximately 2,000–2,200 pelicans, 48,000–51,000 flamingos, 380–460 swans, 27,000– 32,000 geese, 2.0–2.4 million ducks, 2,300–2,800 cranes and 370,000–410,000 coots wintering in Iran. The number of birds reaching Iran in autumn and remaining throughout the winter was greatly affected by weather conditions both in Iran and in the north Caspian region. In mild winters, large numbers of the hardier species, notably the swans Cygnus spp., remained throughout the winter in the north Caspian, while in extremely severe winters, a large part of the Russian wintering populations moved south into northern Iran. In dry years, when many of the wetlands in Khuzestan, central Fars and Seistan remained dry throughout the winter, large numbers of waterbirds continued on south to winter in the Indian subcontinent or Mesopotamia. In the winter of 1969/70, when conditions were unusually mild in northwestern Iran, large numbers of birds overwintered in the wetlands of the Urumiyeh basin in Azarbaijan, but in most years these wetlands froze over in December, and most birds had left the area by the time of the mid-winter counts.