Feeding ecology of the sand shrimp Crangon hakodatei Rathbun, 1902 (Decapoda: Crangonidae) in the East Sea of Korea

The feeding habits of the sand shrimp Crangon hakodatei in the East Sea (Korea) were investigated through analysis and comparison of the stomach contents of 602 individuals according to season, shrimp size class, and prey diversity. The diet of C. hakodatei consisted of 17 prey categories mainly comprising crustaceans, molluscs, polychaetes, nematodes, algae, and fishes, with crustaceans dominating the diet. Molluscs, nematodes, and fishes were also important prey, whilst other categories including polychaetes and algae comprised small percentages of the diet. For small C. hakodatei individuals (<10 mm carapace length [CL]), amphipods and mysids comprised more than 67% of the prey in both relative abundance and frequency of occurrence. Large individuals (>10 mm CL) tended to be more dependent on amphipods than mysids. Amphipods and mysids together constituted the dominant prey, accounting for more than 50% of the diet in terms of both percent occurrence and relative abundance. The abundance and occurrence of prey showed a seasonal variation, with amphipods and mysids being the predominant prey in autumn (45%), winter (30%), and spring (40%). Amphipods were the dominant prey with regard to season, size class, sex, and area.