Bubo bubo (Linnaeus, 1758)
Bubo maximus Sibb.: Finch, 1859: 381; Radakoff, 1879: 167; Reiser, 1894: 104; Bubo maximus Flemm.: Farman, 1868: 204; Elwes, Buckley, 1870: 76; Hristovich, 1890: 192; Jordans, 1940: 134; Bubo ignavus Rchw: Klain, 1909: 91.
Conservation status: in Bulgaria: Endangered EN=[B-1], BDA-II, III; International: CITES-II, BeC-II, ESC-Spec 3, BD-I.
General distribution. A Palearctic species whose area embraces Western and Central Europe, the Apennines and the Balkan peninsulas, the region beyond the Caucasus Mountains, the European and the Asian part of Russia, Iraq, Iran, Turkey, Jordan, Syria, Israel, Northern Indochina, Sakhalin island.
Distribution and abundance in Bulgaria. Resident. Until the middle of the 20th century, it was rather frequent in valleys and mountains at altitudes of up to 1 700 m . Until the 1990s, it was found at altitudes of up to 1 400 m with total numbers of 120-150 breeding pairs . It is most common at places of altitudes of 100-300 m , more frequently in the karstic belt of the area in front of the Balkan range [4, 5]. The numbers were estimated at 120-150 , 100-150 , 125 , 600-700  and 420-490  breeding pairs.
Habitats. Hard-to-access sites, rarely visited by man, mainly in rock massifs and screes, caves, the environs of forests, thinned old forests, often in river valleys near the river.
Biology. Monogamous. The breeding season is from February to August. The female lays 2-4 white eggs. Incubation continues for 34-36 days. During that time she is fed by the male. The young ones fly away at the age of 7 weeks. It mainly feeds on small mammals(hamsters, hedge-hogs, hares, wandering domestic cats). Its frequent prey are birds: domestic doves, turtle-doves, thrushes, small magpies, ducks, partridges, etc. The hunting area has a radius of 1-2 km.
Similar species. None.
Negative factors. Shooting by poachers, destruction and change of the habitats, disturbance, poisoning by victims (mouse-like) of rodenticides.
Conservation measures taken. Protected according to the Biological Diversity Act. Included in the Red Data Book of Bulgaria (1985). About half of the breeding places fall within Protected Natural Territories. A slogan was published for the protection of the species.
Conservation measures needed. Inclusion in Protected Natural Territories of its non-protected habitats, mainly in the valleys. Increase of the nature conservation culture of the population.
References. 1. Patev, 1950; 2. Simeonov et al., 1990; 3. Simeonov, Michev, 1985; 4. Simeonov, 1985; 5. Simeonov, Boev, 1988; 6. Kostadinova, 1997; 7. Kostadinova, Mihailov, 2002; 8. Nankinov et al., 2004; 9. Iankov (in press).
Authors: Zlatozar Boev, Yordan Hristov, Dobromir Domuschiev