Common Pochard

(Aythya ferina)

Category of conservation concern (IUCN, 2020) – Vulnerable

Population size: 2020: 69 -266 pairs (2007: 100-250 pairs)

Distribution pattern

With grouped and dispersed distribution, mainly along the Danube River and the Black Sea coast, where the main breeding sites are situated: Srebarna Lake, the Fishponds Mechka and Orsoya, the Burgas wetlands and especially in the Poda and Komlushka Plains. Single pairs breed in certain years in the Thracian Plain, the Danubian Plain and the Sofia Field, at some sites in Western Bulgaria, and along the Arda River valley.

Population estimation for the period 2013 – 2020: During the period 2013-2020, the species was not found in some old breeding sites, but there was an increase in the number in some key localities. A decrease was observed mainly in the former fish farms, which are abandoned and the water regime is severely disturbed. The species has been gradually increasing its presence and numbers in the country since the middle of the last century. The main breeding habitat is located in the region of the Burgas Lakes, where almost one third of the breeding pairs are registered.

Population size in Special Protection Areas of Natura 2000: 69-239 pairs (100% of the population). The highest numbers have been registered in the SPAs “Mandra-Poda Complex” (13-40 pairs), “Burgas Lake” (9-36 pairs), and “Belene Islands Complex” (10-28 pairs). Virtually the entire breeding population is found within the territory of the national ecological network.

Comparative distribution of the species compared to the first breeding birds atlas (Iankov, 2007): Breeding locality until 2007 | Breeding locality until 2007, confirmed after 2015 – | New breeding locality after 2015. – The breeding localities after 2015 are identified on a base of raw data from smartbirds.org.

Habitats

Breeds in non-marine waters (lagoons, standing fresh waters, standing brackish waters), in bogs and marshes (water fringe vegetation) and in humid grasslands, when situated on the banks of the wetlands. Prefers relatively open and extensive natural and semi-natural wetlands.

Trends in population changes for the period 2013-2020

Threats

Changes in the management and in the use of artificial wetlands leading to drainage of some of the water bodies, accelerated succession, and overgrowing with water-loving vegetation. Deteriorated water regime of the natural wetlands and the associated succession of the vegetation. The main breeding sites are threatened by possible activities for deepening of the Danube River for improving the navigation on the river, which may lead to deterioration of the water regime of the main breeding sites of the species. Urbanization of areas near the coastal lakes, and drainage of natural wetlands along the Black Sea coast.

Nikolay Petkov, Svilen Chesmedjiev