Estimation of survival rate in the early stage of released artificial young abalone by the capture-recapture data

The artificially cultured young abalone Haliotis discus hannai of individuals were released in the survey area of Iwate prefecture for estimating the mortality rate. The population size and mortality rate were estimated from the data of the recoveries from the multiple experiments using the Petersen method, Bayes estimation method and revised Jolly model. Validity of these estimations was examined by the same method in the test tank. The Bayes method gave the stablest estimation under the condition that there is no immigration and the initial population size is known. The value of the mortality rate estimated by the Bayes method was 0.0162•day-1 during the first 23 days after the release. The decrease of resource was divided into death and emigration using the Skellam model. It was shown that the decrease of abalone was caused mainly by death.