Feeding habits of Solenocera melantho in the northern East China Sea.

Abstract

The feeding habits of the mud shrimp Solenocera melantho were determined based on the analysis of 720 stomach contents sampled in the northern East China Sea during June 2009 and May 2010. The diet of the specimens was studied in relation to the season, sex, size class and reproductive condition. The diet of S. melantho consisted of 43 different prey categories, which belonged to small crustaceans, protozoa, polychaetes, algae, fishes and molluscs. Among these, crustaceans, foraminifera and polychaetes made up the main diet of S. melantho with 34.7%, 29.4% and 12.4% in abundance, respectively. Diet composition showed seasonal fluctuation and ontogenetic change. The predominant prey was foraminifera, algae and invertebrate eggs in spring, foraminifera, fishes and polychaetes in summer and autumn, and polychaetes and foraminifera in winter. The feeding intensity was high in spring and summer, and low in autumn. The small size group (<24 mm CL) tended to like foraminifera and algae, while the large size group (≥24 mm CL) preferred polychaetes and crustaceans. Females with advanced ovaries also displayed low stomach fullness, suggesting that feeding activity was affected by the reproductive cycle. S. melantho displayed a high food niche in both sexes and each season, which could be attributed to the fluctuations in available resources. The average trophic level of the S. melantho in four seasons was 2.67, indicating that the species in the northern East China Sea was of low-level carnivores.