Ivanov G. A. RussiaSaratovSaratov State University, 33 Astrakhanskaya Str., Saratov 410012, Russiaecoton@rambler.ru Author's articles STRUCTURAL DYNAMICS OF THE SPAWNING ANURAN TAXOCENOSES IN FLOODPLAIN LAKES OF THE MEDVEDITSA RIVER VALLEY (SARATOV REGION) Reproductive ecology of Anuran Amphibians: Effects of internal and external factors