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In 2012-2013, six parks and urban forests in Kiev with a different level of anthropogenic load were investigated. Twenty-six species of ants from three subfamilies were found in the studied localities with oak (Quercus robur) forests and parks. The ant assemblages are classified into three types according to the number of dominants and their territoriality: (a) mono-and bidominant continuums of associations with weakly territorial dominants Lasius emarginatus and L. fuliginosus, having the highest population densities, and the "behavioral" dominant Camponotus ligniperdus; (b) monodominant associations with a territorial dominant (species of the Formica rufa group); (c) degraded associations in the parks where the dominants are absent and are substituted by the influents Lasius niger and Myrmica rubra. Continuums of associations with weakly territorial dominants have a more developed structure as compared with a monodominant association with the territorial dominant F. rufa producing considerable pressure on the subordinate species. Dominants, subdominants, and influents manifest different types of foraging strategy. A dominant and a subdominant can interchange individual foraging strategy and mobilization; in influents, the strategy remains constant. When the mobilization strategy is used by an influent, only the number of the mobilized workers can be modified, especially in the association without a dominant. Thus, dominants and subdominants have a more flexible foraging strategy due not only to the environmental conditions, but also to the more tight interrelations between the species. With the growth of anthropogenic load the territorial dominant F. rufa increases its pressure upon the subordinate ant species, reducing the intensity of mobilization of their workers to bait. Ant assemblages in the broad-leaved forests of Kiev consist of five chorological complexes, where the leading and layer-connecting role is played by the climbing herpetobiont Lasius emarginatus and the multilayer species F. rufa and L. fuliginosus. Degradation of the associations leads to the disappearance of the species of the two above complexes, disconnection of the layers, and, following the impoverishment of the association structure, weakening and disappearance of hierarchical links. As compared with other cities studied, Kiev has less anthropogenically disturbed ant assemblages with distinct hierarchical structure where the typical forest species F. rufa, L. fuliginosus, L. emarginatus, and C. ligniperdus may act as dominants. Preservation of ant assemblages in Kiev is ensured by the forests and parks present within the city.

General patterns of transformations in multispecies associations of ants in urbanized areas are revealed. The most vulnerable species in the assocation is the species that occupies the second rank in the hierarchy. As the association of the same type degrades, the subdominant species gradually disappears and then re appears in the community. A monodominant association dominated either by a territorial species or by a weakly territorial species degrades towards a simplified community that consists of one species of a rather high rank in the hierarchy (a weakly territorial dominant or subdominant) and one or two influent species. Bidominant associations without subdominant species are derivates of partly degraded monodominant asso ciations with a weakly territorial dominant species.

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