The Food and feeding relationships of Snapper (Chrysophrys auratus) and some other fish-species trawled in Hauraki Gulf

Abstract

Feeding is examined in the eight most common demersal fish species taken by trawling in Hauraki Gulf. 1571 alimentary samples were used. The food table for each fish species is based on occurrence and on a modified points system of food analysis. All eight species feed on elements of the bottom fauna, with Crustacea the most important food group. Snapper (Chrysophrys auratus) is the most abundant fish - its abundance is probably explained by its greater diet diversity and smallest percentage of feeding overlap. Snapper feeding was studied temporally and spatially. Size of snapper, bottom, depth, time of day and geographical regions affected the occurrence and importance of food items, while season and sex did not. Analyses of food selection at specific stations showed that active interspecific competition was rarely present. Only for the three prey species, Hemiplax hirtipes. Tenagomysis macropsis and Amphiura sp., was slight competition noted.