Seasonal, diel and ontogenetic variation in feeding patterns of small yellow croaker in the central Yellow Sea
Abstract:Stomach contents of 1603 small yellow croaker Pseudosciaena polyactis, sampled from seasonal bottom trawl surveys in the central Yellow Sea between March 2001 and January 2002, were examined. The results showed that small yellow croaker was a carnivorous predator and >30 prey species were identified from stomach contents analysis. Crustaceans (mainly euphausiids and decapods) were the most important prey, occurring in 93·1% of the stomachs containing food, and accounting for 77·6% of the total food by mass. Feeding activity was highest in autumn and lowest in spring and winter. Decapods were more important in summer, whereas euphausiids were more important during other seasons. Ontogenetic differences were found in the diet composition and feeding activity within the range of size (standard length, LS) studied. The importance of fishes and decapods increased with LS, whereas euphausiids, copepods and amphipods decreased in importance with LS. Dietary breadth increased markedly for adults. A positive relationship was found between LS and prey size. In each season the maximum diel feeding activity occurred at 0800 and 2400 hours, indicating that there was crepuscular and nocturnal feeding by small yellow croaker.
Document Type: Regular Paper
Affiliations: 1: Fisheries College, Ocean University of China, 5 Yushan Road, Qingdao 266003, China and 2: Key Laboratory for Sustainable Utilization of Marine Fisheries Resource, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, 106 Nanjing Road, Qingdao 266071, China
Publication date: July 1, 2005