Study of larval growth and population estimation of Rana ridibunda in Anzali wetland

According to many literatures Rana ridibunda probably has the potential to become a commercial species which was exploited at least once about 30 years ago in Anzali wetland region. In this study, the larval growth was surveyed at 5 stations in Anzali wetland and the sampling was performed by sieve every 10 days and 2200 larvae were measured and grouped in length frequency classes. The population estimation was done at 20 stations by Jolly-Seber and Leslie methods. The results showed that the maximum length and weight of larvae were 87.7 mm and 5.1 gr respectively. Frequency of total length classes higher than 56 mm and body length more than 26 mm were very little. The findings showed that total frequency of larvae decreased as time proceed. Mortality rate of larva was very high about 97 % and first metamorphosed specimen was observed at early June after about 43 days. According to this study the average survival rate of Rana ridibunda in all studied stations was 0.64 ± 0.16 percent and the average population density was 1.033 N/m2. Maximum sustainable yield was estimated to be about 0.304 individual/m2.