Seasonal development of harpacticoid copepods in the North-East of European Russia

Data of more than 30 years about the harpacticoid copepods of the North-East of European Russia were used to investigate planktonic and benthic species in different types of water bodies. All 28 species and subspecies of harpacticoids known for the study region were found in summer. In spring, Attheyella nordenskjoldi nordenskjoldi and Moraria brevipes reproduced in the rivers and Canthocamptus staphylinus staphylinus bred in temporary water bodies. In the investigated river, the harpacticoid abundance was controlled primarily by water level, while in lentic habitats water temperature determined the formation of egg-sacs in females. Temperature conditions also influenced the speed and duration of ontogenesis. Timing of reproduction of the widespread and dominant species varied depending on temperature conditions for each area of the region under study.