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Quantitative estimate of importance of Amu-Daria valley as a flyway for birds migrating across the Karakum desert

2001; Elsevier BV; Volume: 47; Issue: 2 Linguagem: Inglês

10.1006/jare.2000.0725

1095-922X

Victor N. Bulyuk, Allamurad K. Shamuradov,

Rangeland and Wildlife Management

The purpose of the present work was to establish the importance of Amu-Daria valley as a flyway for birds migrating across the Karakum desert. The authors observed bird passage at two nearby sites: in the typical desert landscape in the south-eastern Karakum and in the valley of Amu-Daria. Counts were done in spring and autumn of 1981 and 1990. To get quantitative estimates of diurnal movements of birds at all altitudes the visual observations and two optical methods were used. The data show that the vegetation strip running from north to south along the Amu-Daria valley does not play a major role as a flyway for many migratory birds in crossing the arid belt of Central Asia. Practically all groups of birds that cross the arid belt, including those ecologically connected with water or humid habitats, migrate over both river valleys and desert areas. The overall flow of migration over the south-eastern part of the Karakum recalculated for 1km at all altitudes in seasonal directions nearly equals the flow over Amu-Daria valley in autumn. In spring the flow of birds over the desert exceeds several times the flow over the valley.