FEEDING OF PENAEUS-JAPONICUS BATE (DECAPODA, PENAEIDAE) IN POND CULTURES - SIZE DESCRIPTORS AND FOOD SELECTION

The feeding pattern of Penaeus japonicus Bate, cultured at different d ensities, with and without the addition of artificial diets, is invest igated in the present paper, to identify any character of prey influen cing the feeding preferences of shrimps. Biometric, calorific and gut contents data of shrimps at different developmental stages were record ed, as well as the abundance of benthic prey. A larger size is correla ted with an increase of energetic value in the shrimp tissues, as conf irmed by the logarithmic relationship between length and weight. Resul ts indicated that artificial diets are chosen at the same rate in each size class and are a good source of energy for shrimps. P. japonicus is able to use different food sources, and its feeding preferences Var ied according to its size. The preferred prey were polychaetes, Chiran omus larvae and bivalve molluscs. Young specimens, however, preferred certain items, such as copepods and Abra ovata, while adults also used amphipods and other mollusc species. Results may be related to the di fferent size and shape of prey.