Environmental grouping of freshwater rotifers (Rotatoria)

The study is devoted to trophic assessment of reservoirs of Kabardino-Balkar Republic. The basis of food supply for fishes is waterbodies on which the bioproductivity of ponds depends. For larvae practically of all fishes, irrespective of the nature of their food up to adulthood rotifers are the main nu-trition. There was the need of studying the biology of major groups and types of rotifers, definitions of their production in ponds, role estimates in the food of fishes. It should be noted that the range of food of all species of fish at larval stage of development is similar. On the basis of the obtained data specific production (R/V-coefficient) which can be used in fishery practice for the assessment of bioproduction of reservoirs was calculated. 10 nursery and 10 finishing ponds during 2008-2015 were investigat-ed. Collecting fresh-water rotifers was carried out two times a month according to Epstein’s system which is simple system adaptation for quality collec-tion of zooplankter, and also by the techniques de-scribed by N.M. Bessonov, Yu.A. Privezentsev. By consideration of the question of trophic chain of reservoirs studied that part which is used in fage by a certain type of nekton at this age stage. The zoo-plankton is investigated on experimental and pro-duction ponds, generally presented by widespread forms, characteristic for eutrophic reservoirs of pond type. 56-85 types of the hydrobionts belong-ing to three main groups - Rotatoria, Cladocera, Copepoda were revealed. Dominant position on the number was everywhere held by rotifer (Rotatoria) - 50-73 species and subspecies. Conducted re-searches repeatedly confirmed the regularity of increase in specific variety noted earlier in the community of rotifers in the ponds of Kabardino-Balkar Republic with I on the V fish-breeding zone (from mountain to steppe) at general increase in the number of hydrobionts. In general so far in vari-ous types of studied reservoirs of Kabardino-Balkar Republic 216 species and 45 Rotatoria forms are known. The vast majority of them is given for the first time for the republic, 18 types and forms - for the first time for Russia.