A skeletochronological estimation of age structure in a population of the Guenther’s frog, Hylarana guentheri, from western China

Abstract

Age determination in amphibians is crucial to investigation of life-history traits. In this context, we studied age structure of the Guenther’s frog, Hylarana guentheri, population from southwestern China located at an altitude of 300 m using skeletochronological method. Our results showed that age in adult males ranged from 1 to 4 years, and from 2 to 6 years in adult females. Average age in females was significantly older than males in 2008 and 2009. Also, females had significantly larger average body size than males in both years. A significant relationship between age and body size within each sex was found in this species for both years. The ANCOVA analysis revealed that there was significant difference in body size between sexes when the effect of age was removed. The von Bertalanffy’s model showed that females had larger asymptotic body size than males, but growth rate of females was smaller than males.