Little Grebe
Tachybaptus ruficollis (Pallas, 1764)
Colymbus ruficollis Pallas, 1764, Vroegs Cat. Adumbratiunculae, 6; Podiceps minor L.: Elwes, Buckley, 1870: 341.
Order Podicipediformes
Family Podicipedidae
Conservation status: in Bulgaria: Vulnerable VU=B[1(b(iii+iv)c(iii))]C[2(i)], BDA-III; International: BeC-II.
General distribution. A Palearctic species whose breeding area embraces Europe, Northwestern Africa and the eastern coast of the Mediterranean. The European population is estimated at 99 000 – 170 000 pairs [1].
Distribution and abundance in Bulgaria. A breeding summer visitor, passage migrant and winter visitor. In the past it was ubiquitously distributed near marshes, rivers and pools, although not very often incubating, with 50 breeding breeding places of Northwestern Bulgaria, near the Danube, the Black Sea coast, in the region around Sofia, the valleys of the rivers Struma and Maritsa [2]. At present there are no significant changes in the distribution of the breeding breeding places. In the 80s its numbers were estimated at 200-300 breeding pairs [1]. On the basis of studies made (1981-86), total numbers of up to 1 500 breeding pairs are supposed [3]. Recently it has been estimated at 3 000 – 3 500 [4] or 800 – 1 900 breeding pairs [5]. The numbers of the population wintering in the country amounts to 635 individuals at the average with a maximum of 881 in 2000 [6]. The major concentrations are in the non-freezing large water basins of Southern Bulgaria: the Maritsa-Iztok Complex, ballast quarries along the rivers Maritsa and Tundzha and the Black Sea coast [3].
Similar species. None.
Habitats. Freshwater fish farms, lakes and microreservoirs with an open water surface and vegetation.
Biology. It breeds in rush with a density of 30-40 stems/m2; laying the eggs (6,1 at the average) takes place between 10 May and 31 May and the first ten days of June; lethality reaches 86% and often has to do with the numbers of the water ray [3].
Negative factors. Decrease of the area of freshwater fish farms because of a change of their use. Destruction of the overgrowths of reed and rush. Purposeful killing by lessees of water basins.
Conservation measures taken. Protected according to the Biological Diversity Act. A considerable part of the breeding places is included in the Natura 2000 protected zones.
Conservation measures needed. Measures must be envisioned in the future Management Plans of the territories included in Natura 2000 against killing and disturbance of breeding birds by lessees of fish farms and microreservoirs.
References. 1. Wetlands International, 2002; 2. Simeonov et al., 1990; 3. Nikolov et al., 1986; 4. Nankinov et al., 2004; 5. Iankov, in press; 6. Michev & Profirov, 2003.
Author: Hristo Nikolov
