The diet composition of juvenile Korean piscivorous chub, Opsariichthys uncirostris amurensis were studied using 277 specimens collected from January to December 2004 in the surf zone of Nakdong river estuary. The size of Opsariichthys uncirostris amurensis ranged from 2.6 to 9.1 cm in standard length (SL). Opsariichthys uncirostris amurensis was carnivore that consumes mainly amphipods and insects. Its diet also included small quantities of polychaetes, fishes, and algae and plants. Opsariichthys uncirostris amurensis showed ontogenetic diet change. Smaller individuals (< 4 cm SL) mainly consumed amphipods. The portion of these prey items decreased with increasing fish size, and this decrease was paralleled with increased consumption of larger preys such as polychaetes and fishes. Insects were preyed moderated values in all size classes. Opsariichthys uncirostris amurensis diet also showed diel change with consuming more on amphipods and polychaetes during day.

• 백근욱 | GunWook BAECK
• 허성회(경상대학교 해양생명과학과/해양산업연구소) | Sung Hoi HUH (Department of Marine Biology &#x0026; Aquaculture / Institute of Marine Industry, College of Marine Science, Gyeongsang National University, Tongyeong 650 160, Korea)
• 박주면(경상대학교 해양생명과학과/해양산업연구소) | Joo Myun PARK (Department of Marine Biology &#x0026; Aquaculture / Institute of Marine Industry, College of Marine Science, Gyeongsang National University, Tongyeong 650 160, Korea) Corresponding author