Abstract
This paper describes the feeding habits of topshell collected in the coastal area of Aoshima, Kyoto Prefecture during a period from June to October 1984.
The shell fed mainly on the red algae (Gelidium sp. and Corallinoideae) and the brown algae (Sargassum spp., Sphacelaria spp., Dictyota dichotoma and Punctaria latifolia) in the night In the daytime, on the other hand, only the brown algae such as Sphacelaria spp. and Sargassum spp. were found in the stomach.
The weight of stomach contents was higher during night than daytime and most starved shells were found in the daytime.
Above results suggest that feeding time of the shell is mainly night time and that Gelidium is more important food for the shell compared with brown algae such as Sphacelaria spp. and Sargassum spp., because of the quicker digestion of Gelidium.
