Tetrax tetrax (Linnaeus, 1758)
Otis tetrax L.: Reiser, 1894: 162; Klain, 1909: 120; Patev, 1950: 314; Boev, 1985: 103
Conservation status: in Bulgaria: Extinct EX, BDA-III: International: IUCN-NT; BeC-II, BoC-II, ECS-Spec 2, BD-I.
General distribution. A paleoxeric species common in Portugal, Spain, France, Italy, the Ukraine, Southern Russia, Kazakhstan. It winters in Portugal, Spain, France, Italy, Morocco, Algeria, Tunisia, Turkey, Kazakhstan.
Distribution and abundance in Bulgaria. Rare passage migrant and winter visitor that in the past probably bred in the country until the 50s of the previous century . In the last third of the 19th century and in the first half of the 20th century it was found (also in spring and summer and during the breeding period) near the village of Gabrovnitsa (Montana region), near the rivers Vit, Osam, Iskar (Pleven region), between the villages of Suvorovo and Vetrino (Varna region), near the town of General Toshevo and the villages of Beloklas, Krasen, Prisad and Karvuna (Dobrich region), between the town of Asenovgrad and the city of Plovdiv, in the regions of the cities/town of Haskovo, Pazardzhik, Stara Zagora, Sliven, Yambol, Burgas, near Kazanlak, Karnobat, Aytos, Kameno, in the Radomir and Sofia fields (the villages of Voluyak, Mramor, Kostinbrod, Bozhurishte, Petarch, Gurmazovo, Kubratovo, the town of Novi Iskar and the village of Kovachevtsi . In 1970-1980 it was reported near the village of Staroseltsi (Pleven region) , the Taukliman locality (Dobrich region) and the town of Valchidol  etc. Numbers: unknown. At the end of the 19th century its numbers declined considerably because of the enlargement of agricultural areas . Up to 10 individuals  are believed to be wintering in the country, but it has not been registered so far during the yearly mid-winter counts since 1977.
Habitats. Steppes and high-grass large and flat terrains (fallow lands, abandoned agricultural areas in flat and mountainous fields and foothill slopes. It settles secondarily in cultured steppes, meadows, pastures, hemp-fields, vineyards and places overgrown with Spear-grass, thorns and other bushes.
Biology. Ground-nesting, monogamous. It lays 2-6 eggs that incubate for 20-22 days. During the incubation the male guards the nest. It feeds on ground slow-moving insects and other invertebrates, on small vertebrates and vegetation parts.
Similar species. The Great Bustard (Otis tarda).
Negative factors. Destruction and change of habitats (ploughing, planting monocultures), disturbance, illegal hunting, killing young birds when gathering crops by harvesters with no safety equipment fitted.
Conservation measures taken. A protected species as of 1962, included in the Red Data Book of Bulgaria. Possibilities are discussed for developing a long-term programme for captive breeding and the release of birds in steppe flat reserves; for focused ecological optimization of the regions for re-introduction – planting of various grass species characteristic of the region; for the elimination or decrease of disturbance during the breeding season (April – July).
References. 1. Boev, 1985; 2. Simeonov et al., 1990; 3. Dimitrov, 1981; 4. Kostadinova, 1995.
Author: Zlatozar Boev