Skeletochronological Age Determination and Comparative Demographic Analysis of Two Populations of the Gold-spotted Pond Frog (Rana chosenica)

To obtain demographic information on threatened gold-spotted pond frog (Rana chosenica Okada,1931) populations, we determined the ages of 45 male and 13 female frogs (20 males and 9 females fromCheongwon and 25 males and 4 females from Tae-an) and compared the age structures and growth patternsof the two populations in 2006. The snout-vent length (SVL) and body weight of female frogs were greater thanthose of male frogs in both populations. Male frogs’ ages ranged 2 to 7 years old and females’ ages ranged3 to 6 years old. In both populations, 4 years old male frogs were the most abundant age-sex class. The agestructures of the two populations were significantly different and the growth coefficients of male frogs from theCheongwon population were greater than those from the Tae-an population. The mean age of males from theTae-an population was higher than that from the Cheongwon population. However, the SVL and body weightsof male frogs were not different between two populations and there was no difference between the twopopulations in the mean male SVL at any age. The results could increase our understanding of the life-historyof this threatened frog and may be useful in conservation planning.