Monitoring of Breeding White-Headed Duck (Oxyura Leucocephala) Populations in Central Anatolia, Turkey

Monitoring of Breeding White-headed Duck (Oxyura leucocephala) Populations in Central Anatolia, Turkey Project supervisor: Itri Levent Erkol (Conservation Manager – Doğa Derneği) Project officer: İbrahim Kaan Özgencil (Biologist – Doğa Derneği) Project start and end dates: March, 2016 – September, 2016 INTRODUCTION White-headed duck (Oxyura leucocephala) is a diving duck from stiff-tailed ducks tribe (Oxyurini). It is the only Oxyurini species resident to the Palearctic region [4] and also one of the rarest birds in the region [26]. It is confined mainly to the steppe zones of the Palearctic [5]. The species occurs regularly in 53 countries, in 18 of which it occurs as a vagrant [25]. There are four assumed populations in the world [4] and there is no substantial differentiation across its whole range and no subspecies are recognized until now [5], [6]. Most of the world’s white-headed duck population breeds in Spain, Algeria, Tunisia, Kazakhstan, Turkey, Iran, Afghanistan, Tajikistan, Turkmenistan, Uzbekistan, Armenia, and Mongolia [1], [5], [25]. It is known that most of the world’s wintering population is hold in only seven countries: Algeria, Islamic Republic of Iran, Russian Federation, Spain, Tunisia, Turkey, and Uzbekistan [4], [25]. White-headed duck has been listed by IUCN as globally Endangered (A2bcde+4bcde in 2012’s Red List Assessment) since 2000 [25]. Global population of the species is declining [25]. Global population size in 2002 was estimated by Birdlife International as 7,900 to 13,000 individuals, 5300 to 8700 of which are mature individuals [25]. National Red List Status of white-headed duck in Turkey was determined as Endangered in 2004 [29]. At that time, the estimated breeding population size was 200-250 pairs which was down to 82-168 pairs according to another assessment done in 2013 [28], [29]. Breeding white-headed duck population in Turkey is estimated to have declined 40 to 69% in the last 12 years [28]. Main reasons for this decrease are habitat loss due to extensive wetland drainage, hunting and possibly low breeding success [1], [9]. In Turkey, the species breeds mainly in Central Anatolia and surrounding Mediterranean and East Anatolia [3]. Central Anatolia population was estimated as 150-200 pairs by Green et.al. after an expedition in 1987 [30]. Later, in 1989, Important Bird Areas publication yielded a population size of 188-198 pairs in the region [31]. The latest study about the breeding white-headed duck in the region was conducted in (another one is being conducted) 1994 and the study estimated that there were at least 150 pairs breeding in Central Anatolia [1]. Although most of the Turkish population has been breeding in Central Anatolia, Van Gölü in East Anatolia and surrounding lakes and wetlands has started to harbor high numbers of breeding pairs as well (Mustafa Erturhan, pers.comm). Wintering population in Turkey is mostly confined to the Mediterranean Region and smaller numbers are seen in Central Anatolia, Black Sea and Marmara regions [3]. In 1991, about half of the world’s population wintered in Lake Burdur in the Mediterranean; 10,927 white-headed ducks were seen in the lake [3]. In 2013, only 247 individuals were counted in Lake Burdur [32]. The Black Sea and Marmara regions seem to be increasing in importance for wintering white-headed ducks. In Mid-winter Waterfowl Surveys in 2013, 1,621 white-headed ducks were counted and 1,253 of these were from Marmara Region [32]. White-headed ducks favor shallow lakes or shallow parts of the lakes for breeding [5]. Although, water depths not exceeding 2.5m (usually less than 1m) are preferred, in places where there are floating vegetation masses like Sultan Marshes, the species can breed in waters as deep as 5m [1], [5], [30]. The species needs open pools which are flanked by dense vegetation which provide cover and nesting sites [5], [30]. Although the species mostly breeds in fresh water bodies, there also many records of use of saline and alkaline water bodies for breeding [5]. Eutrophic lakes are preferred over oligotrophic and mesotrophic lakes simply because eutrophic lakes can harbor a higher chrinomid biomass which is the main food source for both breeding pairs and their ducklings [4], [5], [7]. Today, in Central Anatolia, main white-headed duck breeding grounds are Lake Uyuz, Lake Mogan (both in Ankara province), Sultan Marshes (in Kayseri province), Akkaya Reservoir (in Niğde province), Lake Ulaş (in Sivas province). Akkaya Reservoir was home to about 15 pairs before it went dry in 2011. Now, the reservoir is back to good water levels and there are 3-4 pairs breeding there (Prof.Ahmet Karataş pers.comm.). Lake Ulaş harbored 3-4 pairs in the 2013 and this year there were 3 pairs breeding in the lake (Ferdi Akarsu pers. comm.). Breeding populations in Lake Mogan, Lake Uyuz and Sultan Marshes were the subject of this project. Although, there haven’t been any studies about breeding white- headed duck population in Lake Mogan, records from e-bird show that there aren’t many breeding records from the lake. It seems that the lake serves more like a pre-breeding ground, where numbers as high as 34 birds are seen in March and April. Due to its small size, Lake Uyuz never harbored many breeding pairs; a previous survey conducted in 1991 and 1993 suggested a population size 2 to 10 pairs in the lake [1]. In an unpublished study conducted by Doğa Derneği in 2014, the population size was estimated to be around 9-10 pairs. Breeding population in Sultan Marshes was estimated as around 20 pairs in 1991, before the marshes went dry [1]. There used to be other breeding grounds in Central Anatolia including the vast marshes of Ereğli and Hotamış [1], [3]. Those places have almost completely been dried by The General Directorate of State Hydraulic Works (DSI) during the last 20 years. Ereğli Marshes’ white-headed duck population size estimated as 30-35 pairs and Hotamış Marshes’ population was estimated as 40-50 pairs in 1991 [1]. Lake Kulu was another place where white-headed duck were breeding [3]. The breeding population there was estimated between 30-40 pairs in 1991 [1]. The lake is no longer used by white-headed ducks for breeding. The reasons behind this are not very well known [3]. It should be noted that there are and have been many reports from other small water bodies throughout the region. This calls for an immediate need for detecting and monitoring of these small sized water bodies because they me harboring surprising numbers of white-headed ducks. Future studies aiming at discovering and monitoring of possible white-headed duck breeding grounds in Central Anatolia should be encouraged. Turkey along with Russia has the highest percentage of threatened bird species (about 10%). Main problems for white-headed ducks living in Turkey are habitat loss and degradation, hunting, trapping in fishing nets, lead poisoning and competition with carps over food sources [4], [9]. Habitat loss and degradation occurs as a result of catastrophic water policies of DSI including wetland drainage and dam constructions. A good example can be the case of Ereğli Marshes and Hotamış Marshes. These two used to extensive, so extensive that some people used to call them “seas”. Now they are almost completely dry. Hunting in Turkey is another problem for white-headed ducks and other waterfowl. 2 years ago, the government took the charge of conducting Mid-winter Waterfowl Surveys in the country. Since then, they are corrupting the data and keeping the results secret; the results are no longer public. This corrupted data is then used to set new hunting quotas which are far beyond acceptable range. This year’s hunting quotas are literally death sentences for many of the species. People have run online campaigns, written to the related ministries and governmental bodies, but it didn’t work. The quotas are still the same and many waterfowl and other game birds are killed in numbers that are way too higher than acceptable limits. Hunter are not allowed to hunt white-headed ducks and their meat is not much favored by hunters [9]. Still, due to the lack of an efficient escape mechanism [5] and illegal hunting, white-headed ducks are shot both intentionally and unintentionally. These problems apply to our study sites which are located in Central Anatolia Region. Aim of this study was to monitor breeding white-headed duck populations in two lakes in Ankara province: Lake Mogan and Lake Uyuz. Two other sites were also studied: Mogan Flood Control Dam (a newly discovered breeding ground for the species) and Sultan Marshes. Along with monitoring of the populations in the study sites, detecting and documenting possible threats for white-headed duck populations was also one of the aims of the project. The project also included some social work where our staff informed locals, bird photographers and birdwatchers about the project and the species. Study sites Lake Mogan: Lake Mogan is a medium sized, shallow lake having a surface area of 561.2 ha [20]. It is located in Gölbaşı intercity district of Ankara. Gölbaşı has a total population of 122,288 [8]. The lake is 25 km south of Ankara city center [20] and is surrounded in the North by dense human settlements (Figure 1 below). There are many restaurants and recreation areas along shores of the lake. The biggest recreation area in the region is Mogan Park, which is located on the western shores of the lake. Mogan Park is big park; it has a total area of 203,650 square meters and is visited by hundreds of people every day [20].

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