Место издания:University of Salzburg Salzburg, Austria
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Последняя страница:100
Аннотация:The formation of the first populations of Pelophylax ridibundus in the middle Kamchatka was the result of single successful introduction by humans in the late 1980-s. At the present time, more than 20 localities were revealed in Kamchatka, most of them – in habitats with high supply of warm water all year round. In these populations, up to 8 offspring cohorts were recorded during a year. But in habitats with minimum warm water supply, only one cohort was revealed within each generation. In the Middle Ural, the new introduced populations of this species were formed in warm waters only. Besides two summer cohorts, one wintering cohort was formed, with metamorphosing in spring of next year. Interestingly, small wintering cohort was revealed in one population inhabited “non-warmed” waters.
The unique Rana temporaria population was formed in southern Kamchatka as a result of releasing 150 immature frogs. After 10 years, the numbers of breeding females was already 2,648 ! The activity season duration at the release locality (4 months) is 2 months shorter than that at the original locality of the translocated frogs from Moscow district. Female age at first reproduction is 3 or 4 years, both sexes demonstrate relatively slow postmetamorphic growth and low body length at each age. The presence of a small pool warmed by thermal waters (along with numerous unwarmed ones) and changes in the relationship between larval growth and development promoted this successful introduction.