Spotted Crake
Porzana porzana (L., 1776)
Porzana maruetta Gray et Bechst.: Hristovich, 1890: 216.
Order Gruiformes
Family Rallidae
Conservation status: in Bulgaria: Endangered EN B(1a)+ C(2b); BDA-II, III; International: BeC-II, BoC-II, BD-I.
General distribution. Probably with a European type of distribution, embracing the Northern Black Sea coast, in the north to Arkhangelsk and Ural, in the east to Altai and with separate habitats in Asia.
Distribution and abundance in Bulgaria. A breeding summer visitor, insufficiently studied in the past and without certain proof of breeding [1]. During the multiplication period it was found in the lakes Srebarna [2, 3] and Durankulak [4, 5], in the valley of the town of Botevgrad [6], the swamps around Sofia and the town of Radomir and in the Yambol region [7], the Rose Valley and the Burgas lakes [8; 9]. At present it breeds along the Danube valley, irregularly along the Black Sea coast (the Burgas lakes, the tailings-ponds near the town of Malko Tarnovo) and within the country. The largest habitats are in the Dragoman Swamp and in the other water basins of the Straldzha Swamp [12, 13]. It has also been found in the Sofia field. The numbers are between 200 and 400 pairs, with considerable fluctuations in the different years [11].
Habitats. Large bogs and boggy meadows, mainly overgrown with Carex [11]. It prefers rice fields, turfy marshes and wet meadows along their periphery. In the brackish water basins along the Black Sea coast, mainly wandering and migrating birds are observed.
Biology. Males court from the beginning of April to the first decade of July, continuing for about 10 days. The territorial area of a pair in the Dragoman Swamp is 1,08 ha. The nests are built out of stems of swamp vegetation, hidden in thick herbaceous tufts. The clutch consists of 6-11 eggs, coloured with brown, rusty and light gray dots and spots. It feeds on water insects and small invertebrates [16].
Similar species. The Little Crake (Porzana parva); Baillon's Crake (Porzana pusilla).
Negative factors. Drainage of the bogs; building dikes and roundabout paths; mowing and grazing in the natural habitats; decay of rice production.
Conservation measures taken. Protected according to the Biological Diversity Act. The most stable population (about 40% of the national one) is in the remains of the Straldzha and Dragoman swamps that are proposed for inclusion in the system of protected territories.
Conservation measures needed. Preservation of its habitats; study of its distribution. Mapping and study of the bogs in the country, stimulation of rice production, discontinuation of pastures and mowing in the registered habitats. Carrying out specific hydrotechnical activities preventing the drying up of bogs during the hot summer months.
References. 1. Patev, 1950; 2. Paspaleva-Antonova, 1961; 3. Petrov, Zlatanov, 1955; 4. Simeonov, 1975; 5. Cramp, Simmons, 1980; 6. Simeonov et al., 1984; 7. Hristovich, 1890; 8. Prostov, 1964; 9. Roberts, 1981; 10. Simeonov, 1968; 11. Delov, 2000; 12. Delov, 2002; 13. Borisova et al., 14. Simeonov et al., 1990. 15. Delov, 2002a. 16. Delov, 2002b.
Author: Ventseslav Delov
