Porzana parva (L., 1776)
Porzana minutta Bp.: 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. A Palearctic species whose area is from Siberia to Kazakhstan, Tadzhikistan, the delta of the river Voga, the Caucasus Mountains, the Sea of Azov and along the northern coast of the Black Sea to the delta of the Danube. It breeds irregularly in many countries of Central and Eastern Europe, including the Balkan peninsula.
Distribution and abundance in Bulgaria. A breeding summer visitor with a fragmented distribution; in the past, there were only two certain evidences of breeding [1, 2, 3]. In the second half of the 20th century it was registered during the multiplication period in the Botevgrad valley [4], the swamps around Sofia [5, 6], the Burgas lakes [7; 8, 9], the Rose Valley [10]. At present it breeds along the banks of the Danube (the Mechka fish farms), regularly along the Black Sea coast (the Alepu marshes and lakes Arkutino, Shabla and Durankulak, the most significant breeding place in Bulgaria). Among the places within the country, it incidentally breeds in the swamps of Dragoman and Straldzha [13, 14], in the fish farms near the village of Orsoya, and the drainage canals of the Mladost quarter in Sofia. During migration it is is registered throughout the country. The supposed numbers in the country are between 800 and 1 000 pairs [11].
Habitats. Vast areas of water basins with large, thin reedbeds, coloured with small water mirrors and floating water vegetation; drainage canals thickly overgrown with reed and rush [11].
Biology. Males court from the middle of April to the middle of the first decade of June. The nests are located on the water surface amongst the reed. They are built out of thin stems and leaves of reed. The clutch consists of 6-11 eggs. Both parents incubate. Data of the breeding success are missing. In the autumn, the migratory behavior is manifested immediately after sunset [16]. Food: water insects and small invertebrates [16].
Similar species. Baillon's crake (Porzana pusilla).
Negative factors. Destruction of the habitats, mowing of the reed; burning the reedbeds in the winter.
Conservation measures taken. Protected according to the Biological Diversity Act. The most stable population is in Durankulak Lake, which is a Protected Locality.
Conservation measures needed. Preservation of its habitats; study of its distribution. Mapping and study of all significant reedbeds in the country, permanent monitoring of their state.
References. 1. Patev 1950; 2. Reiser 1894; 3. Paspaleva-Antonova 1961; 4. Simeonov et al. 1984; 5. Simeonov & Sofroniev 1968; 6. Nankinov 1982; 7. Prostov 1964; 8. Donchev 1980; 9. Roberts 1981; 10. Donchev 1977; 11. Delov 2000; 12. Delov 2001; 13. Delov 2002a; 14. Borisova et al. 2005; 15. Simeonov et al. 1990; 16. Delov 2002b; 17. Delov 2002c.
Author: Ventseslav Delov