black sea red data book - Department of Biology

Biology. A breeding and migratory species. Spring migration takes place in April
and is over by early May. Mass egg-laying is in late May, early clutches appear by
the middle of the month. Breeds in loose colonies, often together with terns and other
waders. Clutch size is always four, double clutches of 6-8 eggs may be found in
places of high concentration. Hatching peaks in mid June, or in the second ten days
of the month. Fledglings occur from mid July onwards. Autumn migration is hardly
detectable, post-breeding movements gradually become migration. A sharp decrease
follows in August, the majority leaves by early September. Single birds may stay till
early October. Surface or plankton aquatic invertebrates form the basic diet of Black-
winged stilts, but birds can forage on the ground for insects and spiders as well.
Population trends. Probably a stabilization of numbers in the years ahead.
Threats. Water pollution, cattle grazing, human disturbance, high prédation risk.
Conservation measures taken. Creation of reservoirs within the ranges of water
protection zones in estuaries and coastal lakes.
References
Red Data Book of Ukraine, 1994. 347 pp.
Siokhin V. D., 1.1. Chernichko, T. B. Ardamatskaia et al, 1988. Colonial
Hydrophilic Birds of the South of Ukraine: Charadriformes. Kiev, Naukova Dumka:
176 pp. (in Russian).
Compiled by J. Chernichko
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