Hope for the White-headed Duck, Oxyura leucocephala (Aves: Anatidae) in Turkey despite a declining breeding population and abandonment of its traditional wintering area?

Abstract

The development of the breeding and non-breeding populations of the White-headed Duck, Oxyura leucocephala, in Turkey was analysed based on all available records from the period 1966–2016 from 99 different areas. Breeding is confined to Inner Anatolia and the eastern parts of the country. The breeding population had been estimated as 200–250 pairs in the period 1996–2001 but recent observations show that it does now not exceed 80–125 pairs which is a decline of about 50% within two decades. The non-breeding winter population comprises approximately 8,500–10,000 individuals. Burdur Lake has traditionally housed more than 90% of the population but is no longer a significant resting place. The numbers started to decrease from more than 10,000 birds at the beginning of the 1990s to a few hundred in the early 2000s. Now only very small numbers overwinter there. The reason seems to be a combination of water pollution and decreasing water level. After a period of more than 10 years, the numbers in Turkey started to increase again, and most birds are now concentrated at Manyas Lake in Western Anatolia. In 2016, the population reached a winter maximum of approximately 6,000. In the post-breeding season, up to 4,000 individuals were recorded in Eastern Anatolia in October 2014 which is far more than has ever been recorded in this season before.