Branta ruficollis (Pallas, 1769)
Rufibrenta ruficollis (Pall): Prostov, 1964: 49; Kaltchew, 1964: 295.
Order Anseriformes
Family Anatidae
Conservation status: in Bulgaria: Vulnerable VU [A2(a)], BDA-II; III; International: IUCN-VU, CITES-II, BeC-II, BoC-I, II, ECS-Spec 1w, BD-I.
General distribution. A Palearctic species breeding in the tundra and the forest tundra of the peninsulas Yamal, Gidan and Taimir in Russia. It winters along the Black Sea coast of the Ukraine, Romania and Bulgaria. In 2005, the estimate of the world population was about 38 500 birds.
Distribution and abundance in Bulgaria. A passage migrant and winter visitor around the lakes Shabla and Durankulak (sometimes in Srebarna Lake and the Burgas lakes) [1-10]. Sporadically it winters in reservoirs within the country and the valley of the Danube [11, 12]. Until the end of the 60s, there were singular birds and small flocks of 20-30 individuals [1]. Between 1969 and 1985, its numbers varied widely (up to 16 566 individuals in January 1980) [1, 2]. Between 1986 and 1995, the numbers had a maximum of 59 206 individuals [4] and in the last 11 years they were between 14 266 and 67 795 individuals (up to 71% of the world population) [6, 7, 9, 13].
Habitats. Shore lagoons, freshwater lakes, the sea aquatory in the coastal zone, winter sown fields with corn-wheat cultures, etc.
Biology. It forms small thinned colonies around nests of birds of prey [14, 15]. The breeding success varies in the different years [10, 16]. It feeds on grasses (Gramineae and Cyperaceae), and in the wintering sites on leaves of sown fields with winter wheat, maize and wheat grains, etc. [8, 10, 14].
Similar species. None.
Negative factors. Illegal shooting; poisoning; disturbance in the places for spending nights and for feeding. Change of agricultural cultures, in the mode of managing arable lands. Building tourist infrastructure around the wetlands; building wind turbines. Probably the global change of the climate and bird flu (H5N1).
Conservation measures taken. The species and its habitats are protected according to the Biological Diversity Act. A National Plan for the preservation of the species is enforced. The major sites for spending nights are protected and Management Plans are enforced for them. The key sites for feeding have been specified, some of them were bought by nature-preservation organizations. For 11 years there has been monitoring in the lakes Shabla and Durankulak and campaigns for the control of hunting. There is a good level of information among the population.
Conservation measures needed. Expansion of the existing Protected Territories and declaration of new ones. Inclusion in the Natura 2000 network of places important for the species. Purchasing and renting agricultural lands. Restriction of the building of wind turbines in Dobrudzha. Reduction of the disturbance of hunting. Studies and monitoring.
References. 1. Ivanov & Pomakov, 1983; 2. Michev et al., 1983; 3. Michev et al., 1991; 4. Michev & Profirov, 1997; 5. Dereliev, 1998; 6. Dereliev, 2000a; 7. Dereliev, 2000b; 8. Dereliev et al., 2000; 9. Michev & Profirov, 2003; 10. Dereliev, in press; 11. Kostadinova, 1997; 12. Kostadinova & Dereliev, 2001; 13. Dereliev et al., 2005; 14. Cramp, Simmons, 1977; 15. Dementjev & Gladkov, 1952; 16. Madsen et al., 1999.
Authors: Sergei Dereliev, Pavel Simeonov