Cladocera and Copepoda (Calanoida, Cyclopoida) crustaceans of the Runa, Borzhava, Vododilnyi massifs (Ukrainian Carpathians)

15 species of plankton crustaceans (7 – Cladocera and 8 – Copepoda (Calanoida and Cyclopoida)) from reservoirs of the Runa, Borzhava, and Vododilnyi massifs are noted. The objects of research were found in 13 of the studied reservoirs within the Runa massif, Vodiv­kania and Preluchnyi areas, as well as the upper stream of Husnyi and Zhdenievka rivers; five inhabited reservoirs were found in the Borzhava massif, and three in the Vododilnyi one. Pond size measurements of the Velyka Trustsia and two Borzhava lakes were carried out. The natural glacial origin of the Velyka Trustia lake which is located to the northwest of the top of the Runa massif is doubtful. Most likely it was formed by the erection of artificial dams. Chydorus sphaericus (OF Müller, 1776) and Daphnia obtusa Kurz, 1874 (Cladocera) are the most common species in the investigated area. The highest density of plankton crustaceans was recorded in the reservoirs of natural origin: the Borzhava lake 1 – 170.3 thous. ind./m3, in the meadow puddle of the Vododilnyi massif – 253.5 thous. ind./m3. Daphnia obtusa dominates in these communities with 55–97 % of the total number of crustacean plankton. Under the condition of a low number of reservoirs in this area a high concentration of aquatic diversity, which was observed in single aquatic habitats within the massifs of Runa, Borzhava, and Vododilnyi is very valuable. Their value ability enhances the importance of the reservoirs’ conservation level in preserving the biodiversity of mountain areas. The presence of stenobiotic and endemic hydrobiont taxa (Daphnia obtusa Kurz, 1874, Mixodiaptomus tatricus (Wierzejski, 1883)) indicates that these reservoirs deserve the preservation of the existing natural abiotic conditions of their ecosystems without further increasing the level of anthropogenic pressure. Water bodies of the Vododilnyi massif are oligosaprobic, single water bodies of the Runa and Borzhava massifs are oligosaprobic, while the other reservoirs are β-mesosaprobic. Vehicle and motorbike tourism is the main current negative factor of anthropogenic pressure in the water basins and reservoirs of the studied area. This impact influences the stable existence of natural aquatic ecosystems to a high extent, as all such reservoirs are located on the roadside or close to dirt roads.