WATSON and DAVIS: LARVAL FISH DIETS IN SHALLOW COASTAL WATERS 



larvae contained food in that stratum. Block E is not shown because no larvae occurred there. Water 

 attributable to a given food category; %F0 = the percent of the larvae containing food items that contained 



surveys. In both cases, sampling was mainly 

 after midnight, in contrast to all other surveys 

 when sampling was mainly before midnight. The 

 potential influence of moonlight on feeding inci- 

 dence could not be addressed in this study, since 

 all samples were collected within five days of 

 new moon. However, as noted above, the study 

 by Bagarinao and Hunter (1983) suggests that 

 nocturnal feeding is possible during full moon, at 

 least near the surface. 



Cross-shelf differences in feeding incidence 

 were apparent for 5 of the 12 stage-taxon cate- 

 gories examined; for 4 of these, feeding incidence 

 was higher near shore and lower in seaward 

 blocks. This may reflect a higher level of feeding 

 intensity near shore, but since the nearshore 

 blocks were always sampled earlier than the 

 offshore blocks during each survey, the alterna- 

 tive explanation that these patterns merely re- 



flected the cessation of larval feeding at night 

 cannot be dismissed. The results for Athennop- 

 sis calif omiensis, and perhaps for Leuresthes 

 tenuis, are more likely to represent real, but 

 small-scale differences in feeding incidence since 

 these two species were collected mainly in the 

 two or three shallowest blocks, and relatively 

 little time elapsed between samples. 



The composition of the larval diets described 

 in this study is similar to the diet described for 

 many larval marine teleosts (e.g., Arthur 1976; 

 Sumida and Moser 1980; Hunter 1981) in that 

 major fractions were contributed by copepod 

 nauplii and copepodites. In the present study, 

 the harpacticoid copepod Euterpina acutifrons 

 was an important component of the diets of all 

 six taxa examined. This copepod species has not 

 been noted in other studies as being such an 

 important dietary component and the reason for 



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