The body condition dynamics of Pelobates fuscus toadlets from three local populations (namely, Lakes Sadok, Kruglen’koe and Lebyazhye: the Medveditsa river valley, Saratov region) in the period of their migration from spawning lakes in 2013 is characterized by the bimodality of most parameters. In the population from the waterbody with a constant hydrological regime (Lake Lebyazhye), two peaks of the size and weight traits and body condition of toadlets are formed in this period.