A total of 212 carnivorous coastal fish species from New Caledonia,
represented by 7335 individuals, were analysed for their diet. Fifty two
prey items were identified and later grouped into broader taxonomic
categories refered as “prey types”. For each fish species 6 biological
traits were defined: maximum adult size, major biotope, schooling behaviour,
home range, nycthemeral behaviour, degree of crypticity. A general linear
model was fit to the diet data taking into account these traits, and depth
of capture and fish family. This model was applied to the average number of
prey types/stomach and to the volume of 5 prey types: nekton, crustaceans,
molluscs, echinoderms, worms. A second analysis was performed on the effect
of observed size on diet composition, taking into account these traits and
taxonomy. This analysis was restricted to species with at least five
individuals, representing 113 species from 33 families. More detailed
information is given for the three major families, Serranidae, Lutjanidae
and Lethrinidae and intra-family variations are illustrated for Lethrinidae.
All the factors tested had significant effects on diet, fish size and
taxonomy being the two major factors. The five prey types analysed in detail
displayed marked differences according to the factors studied. In particular
nekton increased in importance with fish size, whereas crustaceans decreased
and molluscs presented a dome shaped relationship. Nekton and crustaceans
made the bulk of the diet of most species, with molluscs being at times
important. Echinoderms and worms were never a major food item and were eaten
only by a restricted range of species.