Picoides tridactylus Brehm, 1831
Conservation status: in Bulgaria: Endangered EN [A4(c, e)], BDA-II, III; International: BD-I, BeC-II.
General distribution. A Siberian-Canadian species with a breeding range including the taiga of Europe, Asia and North America. The subspecies P. t. alpinus is a glacial relict found in the mountains of Central and Southeastern Europe, including the Balkan peninsula, where two meta-populations survived with small numbers.
Distribution and abundance in Bulgaria. Resident. At the beginning of the 20th century it was considered common at some places in the Rila mountain, but until the end of the century it remained understudied and with few registered breeding places in the mountains Rila, Pirin and the Western Rhodopes [1, 2,3]. In 1995-2005, it was found in more places in the three mountains as well as in Vitosha mountain ; Recently it was registered also in the reserves Mantaritsa and Soskovcheto and above Prespa Hut, in the Western Rhodopes (T. Zlatanov, P. Shurulinkov, unpublished information). Numbers: 90-130 breeding pairs; of the Rilo-Rhodope meta-population common for Bulgaria and Greece – 140-230 pairs, of the Western Balkan one – 80 – 290 pairs .
Habitats. Old coniferous, mainly spruce forests with more dying trees, most frequently at altitudes between 1 400 and 1 800 m.
Biology. In Central Europe incubation (usually 3-5 eggs) is from the middle of May to the beginning of June, lasting for 14 days. . In Pirin, feeding the young is at the beginning of June and flying away from the nest at the end of the month ; 95% of the food consists of insects – xylophages and their larvae, found in dying trees with slightly falling-off bark and soft wood [7,8]. In Central Europe it breeds in old natural, mainly spruce forests; the breeding and winter territories are from 40 to 230 ha [8, 9, 10; Z. Spiridonov, L. Mileva, unpublished information)].
Similar species. None.
Negative factors. Felling old coniferous forests and fragmentation of their massifs; sanitary felling. The destruction of forests for building ski tracks in Pirin National Park. The narrow specialization for food and habitat; competition by the Black Woodpecker and the White-backed Woodpecker.
Conservation measures taken. Protected according to the Biological Diversity Act. Included in the Red Data Book of Bulgaria (1985). Declaration of the mountains Pirin and Rila as National Parks, the Rila Monastery as Nature Park, with the strict reserves within their territories, preserving 65% of its population.
Conservation measures needed. Conservation in protected territories of the old natural coniferous forests in the Western Rhodopes and a ban on felling in them. A planned increase of the area of the old forests and restoration of a structure close to the natural one.
References. 1. Spiridonov, 1985; 2. Darakchiev, 1969; 3. Simeonov, 1971; 4. Iankov (ed.), 2007; 5. BirdLife International, 2004; 6. Makatsch, 1976; 7. Fedyushin, Dolbik, 1967; 8. Vladishevskiy, 1980; 9. Scherzinger, 1982; 10. Ruge, Weber, 1974.
Authors: Geko Spiridonov, Petar Shurulinkov, Tsvetan Zlatanov