Gadwall

(Mareca strepera) (Anas strepera)

Category of conservation concern (IUCN, 2020) – Least Concern

Population size: 2020: 69-141 pairs (2007: 70-120 pairs)

Distribution pattern

Species with a small population and with dispersed breeding sites, grouped in neighbouring squares along the River Danube and the Black Sea coast. Main breeding sites are in the Orsoya and Mechka fishponds, the Srebarna Lake and the Burgas Wetlands. As a whole, the distribution pattern is similar to that in Europe. The rather specific requirements of the species for its breeding habitats determines the uneven and patchy character of the distribution. Favours large and overgrown with vegetation wetlands.

Population estimation for the period 2013 – 2020: During the period 2013-2020, the species was found in 41 squares. Its breeding has not been confirmed in five squares, where it was reported before 2013. Deterioration of some of the habitats explains their disappearance. New habitats have been established in two squares – in the Thracian Plain and the Sofia Field. The number of the species has greatly decreased in the main breeding grounds along the Danube River – the Orsoya Fishpond and the Mechka Fishpond Protected Areas. This is due to the neglect of the fishponds and a change in their use. Most of the Mechka Fishponds have been drained and turned into arable land.

Population size in Special Protection Areas of Natura 2000: 67-131 pairs (97% of the population). The highest numbers have been registered in the SPAs “Yatata” (12 pairs), “Belene Islands Complex” (14-26 pairs), and “Srebarna” (2-16 pairs).

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 (coastal lagoons, standing fresh waters, standing brackish waters), bogs and marshes (water fringe vegetation) and humid grassland communities on the banks of the wetlands. The inhabited by the species wetlands along the River Danube are heavily overgrown with water fringe vegetation, while the breeding habitats in the Burgas and the Varna wetlands are more open and with hygrophilous vegetation at the fringe of the water bodies.

Trends in population changes for the period 2013-2020

Threats

Drainage of wetlands, changes in the water levels and in the hydrological regime of water bodies during the breeding season, disturbance.

Irina Kostadinova, Svilen Chesmedjiev