Feeding behavior and food consumption of Japanese whelk, Buccinum isaotakii (Neogastropoda: Buccinidae)

Abilities of detection and preference of food by a Japanese whelk, Buccinum isaotakii, were investigated under laboratory conditions. Consumption per food item and the corresponding assimilation efficiency were also de termined. Whelks were more sensitive to fresh foods than boiled foods, detecting them in a short period of time varying between 3.8 (±0.8) and 23.1 (±3.1) minutes. B. isaotakii preferred fish, polychate and bivalves and the time spent on these foods was more than 10 min as compared with those of shrimp (2.0 min) and squid (1.0 min). The highest daily consumption rate was observed on sardine, followed by scallop, polychaete and oyster. The relationship between shell length and consumption of different food items was positive. The coefficients of determination were relatively high for sardine, scallop, polychaete and oyster (r 2, between 0.46 and 0.51) but not for clam, mussel shrimp and squid (r 2, between 0.003 and 0.176), suggesting that the former could be predators of consumption for B. isaotakii. Observed were relatively high assimilation efficiencies on sardine, scallop, polychaete, and oyster, ranging from 30 to 70%. The present results are the intial information pertaining to the feeding biology of this whelk, thus, in-depth studies like an energy budget are recommended to deepen the understanding about seed production and resource management.