tory, which is benthic in nature (Goldberg 1 1976). 

 Additionally, larvae of 3 to 15 mm length of both 

 these species feed primarily on zooplankton, 

 which have been shown to be most abundant near 

 the bottom in the nearshore San Onofre area 

 (Barnett and Sertic 1979). 



The absence of queenfish larvae in the neuston 

 during the summer, and low concentrations in 

 the midwater compared with the epibenthic 

 level during the same period, may be due to the 

 formation of the thermocline (density gradient) 

 preventing eggs from entering the upper water 

 column prior to hatching. Larvae of G. lineatus 

 are more prevalent in these levels during the 

 winter, when the water column is well mixed. 



Length-frequency distributions of all three 

 larval species are dependent on spawning cycles 

 and behavioral and feeding patterns. Length- 

 frequency distributions are reasonably accurate 

 indicators of spawning periods, dependent on the 

 life history of the species in question. Larvae of 

 larger size classes are generally prevalent dur- 

 ing periods of lowest abundance, after the main 

 spawning period ends. During spawning peri- 

 ods, the distribution is dominated by smaller lar- 

 vae. In distributions of northern anchovy, which 

 apparently spawns intermittently year-round in 

 the San Onofre region, the variability of the 

 length-frequency median from month to month 

 is highest in the neuston net and lowest in the epi- 

 benthos. Northern anchovy larvae apparently 

 migrate from the neuston soon after hatching, 

 but return upon reaching lengths of about 20 

 mm. Superimposed on spawning cycles, this 

 phenomenon induces a high degree of variability 

 to length-frequency medians of neuston samples. 

 Larvae of the two sciaenid species, however, are 

 benthic in nature, leading to increased variabil- 

 ity in epibenthic samples, where the majority of 

 these larvae are collected. At any one time, the 

 major determining factor regulating the length- 

 frequency distribution of these larval species 

 near San Onofre is the reproductive state of each 

 of the species. 



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