black sea red data book - Department of Biology

irds usually breed successfully. The heron preys in open or slightly vegetated
shallow water-bodies, searching for food. Its diet consists mostly of molluscs, insects
and their larvae, small copepods, spiders and leeches. A rare visitor to gardens in the
river valleys, where it may prey on invertebrates after rains.
Population trends. Hard to estimate, since it varies in sub-regions: in some places,
numbers sharply decrease, whereas new colonies appear in others. The population
"balances on the edge" and new colonies may not ensure its stability. Up-to-date
estimates of population size show fluctuations within 200-900 pairs.
Threats. Constant human disturbance, degradation of reed-beds in some regions, and
river pollution. Water pollution and a decrease in feeding capacity in big and small
river deltas as well as disturbance of colonies are the major threats.
Conservation measures taken. Special protection of all new colonies, expansion of
the network of reserves.
References
Kostin Y. V., 1983. Birds of the Crimea. 241 pp (in Russian).
Smogorzhevsk'kyi L. 0,1979. Divers, Grebes, Shearwaters, Cormorants, Shags,
Egrets, Herons, Flamingoes. Fauna of Ukraine. Birds. Kiev, Akad. Nauk. USSR 5:
432 pp. (in Russian).
Stepanian, 1994. Chervona Knyga Ukrayiny (Red Data Book of Ukraine). Kijiv,
Ukrajinska Encyclopediya Publ.: 308 pp. (in Ukrainian).
Compiled by J. Chernichko
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