Study of age and body size in two population of marsh frogs (Pelophylax ridibundus) in north of Iran

The determination of animal´s age is important to obtain information about life history of species, growth, age and longevity or population structure. In amphibians skeletochronology is an effective tool to estimate the age. In the present study, the age structures of 50 samples (30♂, 20♀) in the two populations of Pelophylax ridibundus(Ranaidae) distributed in north of Iran (Rasht and Sari) were determined. The phalangeal cross-sections showed that males are on average older than females. The ages ranged from 4 to 13 years, with an average age of 8.50±2.13 years in males and 6.55±1.40 years in females. Frogs from Sari were older and larger than Rasht frogs. The correlation between age and SVL (the snout-vent length) was positive in both localities. With this study, we obtained new information about age and size of P. ridibundus in north of Iran. These kinds of studies on the same and similar species allow us to understand environmental effects on populations’life history characteristics. The age of maturity will be helpful for planning captive breeding programs and conservation in the future.