Maturity and Clutch Frequency of Female Rana porosa brevipoda in the Northern Ina Basin, Nagano Prefecture, Japan

Abstract

Reproduction of female Rana porosa brevipoda was studied in the northern Ina Basin, Nagano Prefecture, Japan. The age at first reproduction was estimated to be 2 years. The smallest female with mature eggs was 47mm in SVL. Based on the ovarian cycle of mature females, it is suggested that at least some individuals deposit two clutches in a breeding period, and that weights of the second clutches are much lighter than those of the first ones.