Dynamics of reproduction success of waterfowls on different phases of 11-year climatic cycle (Selenga river delta, Southern Baikal)

On the basis of long-term researches (1973-1983) the dynamics of reproduction success of mass species of waterfowls in Selenga river delta (Southern Baikal) the authentic trend of increasing of this index in process of development the 11-year climatic cycle (from coldly and wetly to warm and dry phase), having non-linear character is revealed. Small rectilinear relation of this index changes is found only at diving ducks. Highly authentic equations of curvilinear regression with use of parabolic interpolating are received. In all cases three periods of natural changes of reproduction success of the birds, corresponding to the main phases of cycle of this level are well allocated. On its extent decrease of limiting influence of fluctuations the water level that conducts to increase of reproduction success of birds is observed.