Structure of relationship between fitness components in life history of Rana arvalis. 1. Dynamics of reproductive effort and its components [Russian]

摘要

The influence of dates of metamorphosis, size of animals at the termination of metamorphosis and the number of emerged juveniles on the reproductive characteristics and female body size were studied by group-marking of postmetamorphic Rana arvalis individuals of three generations. The frogs under study were emerged in a breeding pond and their adults were recaptured from the same pond in 3-7-years. The maximum values for the body length, egg diameter and reproductive effort were found in the females born in 1991. This generation was characterized by the maximum size at the termination of metamorphosis and the minimum number of the emerged juveniles. At the same time, similar variations in the mean annual values of the body length, fecundity, and egg diameters in individuals of different generations were revealed. The differences between generations of 1989 and 1990 were expressed more weakly, despite similar size and initial number of the juveniles. A general trend for each generation was an increase of female fecundity and egg diameter (but not reproductive effort) with increasing age. The mean age of mature females originated from early-juveniles were significantly younger than in late juveniles of the same generation. The most of females from the group of late small-sized ones reproduced for the first time after the 4th wintering, i.e. one year later than other groups. The, group distinguished within the generations differed weakly by the reproductive characteristics.