Sylvia borin (Boddaert, 1783)
Conservation status: in Bulgaria: Endangered EN B [1a], BDA-II; International: BeC-II, BoC-II.
General distribution. A species with a European type of distribution. The breeding area embraces almost the whole of Europe, without the southernmost parts of Greece and Italy and Asia .
Distribution and abundance in Bulgaria. A breeding summer visitor. Until the first half of the 20th century it was registered breeding in a scattered manner in different parts of the country [2-7]. It has had a sporadic distribution also since 1950 [8-13]. At present it has scattered punctate breeding places along the territory of the whole country up to 1300 m altitude; in all breeding places under 10 pairs in a UTM square . The total numbers are about 120-250 pairs.
Habitats. Thinned deciduous forests with a rich shrub underbrush, parks, gardens; less often in woody and shrub plantations and in yards in human settlements rich in trees and bushes .
Biology. The nest is in bushes, with a height of usually not more than 1 m. It lays in May. The clutch contains 4-5 (2-6) whitish, poorly spotted eggs. One or two clutches. The female incubates in the course of 11-12 days . The food consists of insects and small fruits.
Similar species. The Barred Warbler (Sylvia nisoria), the Common Whitethroat (Silvia communis).
Negative factors. Destruction of forest habitats and the shrub thicket in the deciduous forests; major felling and other forestry activities during the multiplication period.
Conservation measures taken. Protected according to the Biological Diversity Act. A small part of the population is in Protected Territories.
Conservation measures needed. A more detailed study of the distribution, numbers, biology and ecology aimed at particularizing the threats.
References. 1. BirdLife International, 2004; 2. Finsch, 1859; 3. Radakoff, 1879; 4. Alleon, 1886; 5. Boetticher, 1919; 6. Jordans, 1940 7. Patev, 1950; 8. Petrov, Zlatanov, 1955; 9. Prostov, 1964; 10. Paspaleva-Antonova, 1965; 11. Donchev, 1970; 12. Simeonov, 1973; 13. Petrov, 1981; 14. Georgiev, in press; 15. Cramp, 1988.
Author: Dimitar Georgiev