Studies on the Environmental Condition for Short Necked Clam Survival at the Mouth Area of the Ashida River

Abstract

Short necked clams Tapes japonica were reared by means of feeding with the suspension of mud which were collected from tidelands at the mouth area of the Ashida river. The clams fed with the suspension could survive longer than 19days, though the longest duration of survival was 13days in clams without feeding. Similar effect could be obtained by feeding with the filtrate of the suspension. There were clear differences in the effect of feeding among the muds from 4 different stations at the river mouth area. These differences could explain the difference in recovery which were observed in the releasing test at each station.