Kirikova T. The role of aquatic invertebrates in foraging and distribution of tundra waders in limans and lagoons of the Azov-Black Sea region

For the first time, it was made an assessment of the role of aquatic invertebrates of limans and lagoons of the Azov-Black Sea coast in the foraging and seasonal distribution of tundra species of waders migrating along the Mediterranean continental flyway. For the first time, the resources of aquatic invertebrates were evaluated, predominantly benthic organisms, providing the waders with the energy necessary to migrate to their breeding areas and required in the early stages of the breeding season. The structure of forage items of waders (according to the analysis of their stomachs) included both aquatic and soil invertebrates. The polychaetes Polychaeta (with frequency of occurrence from 27 to 100 %), chironomid larvae Chironomidae sp. (from 44 to 96 %) and small crustaceans Crustacea (from 1 to 65 %) constituted the basis of the diet. The diet was diversified by beetles and their larvae Carabidae, Dytiscidae (from 1 to 40 %), and gastropods Gastropoda (from 1 to 8%). For the first time for the region, it was proved that the distribution of flock species of waders was determined by the size of foraging areas, while the location of the other studied species of waders - by the biomass of forage items. The decrease in the number of tundra waders, observed in recent years at migration stopovers in the south of Ukraine, may be associated with the decrease in forage and changes in the structure of benthic coenoses as well as with the reduction in the foraging areas.