OWEN ET AL.: SPAWNING AND SURVIVAL OF LARVAL ANCHOVY 



mortality rates were statistically indistinguish- 

 able between sites. Mortality due to starvation 

 was about the same at the two sites. Larval 

 production at Site 1 was well above the CalCOFI 

 survey average, but Site 2 production and larval 

 mortality at both sites were similar to those over 

 the entire CalCOFI region. 



Habitat characteristics at the two sites dif- 

 fered substantially. Site 1 was relatively eutro- 

 phic, as seen by its high concentrations of larval 

 forage, zooplankton, chlorophyll, and phaeopig- 

 ment. Site 2 was much more energetic, as seen 

 by its greater wind speed, cuirent speed, mixed 

 layer depth, and depth of ma.ximiim stability. 

 With the exception of predatory copepod abun- 

 dance, every measured characteristic of the en- 

 vironment favored larval anchovy well-being 

 more at Site 1 than at Site 2. 



Yet the well-being of anchovy larvae was 

 about the same at the two sites. Anchovies 

 spawned under conditions where their larvae 

 could gi'ow and survive at about the same rates, 

 despite the differences noted in the respective 

 environments. Similar larval gi'owth rates and 

 the low incidence of starving larvae indicate 

 adequate forage availability in both habitats. In 

 agreement with MacCall's (1983) Basin Model, 

 rates of larval anchovy mortality at the two sites 

 were not greatly different and the same fraction 

 of the original larval production survived to the 

 schooling stage. 



We consider this work to be a pilot effort to 

 stimulate and guide research that we hope will 

 be more experimental in scope and execution. To 

 test our hypotheses, environments that more 

 completely span the "suitable basin" need to be 

 described and occupied long enough to follow 

 characteristics of larval fish cohorts from egg to 

 metamorphosis. 



ACKNOWLEDGMENTS 



This work is dedicated to the memory of Dr. 

 Reuben Lasker: he was our friend and guide. We 

 acknowledge and appreciate the wiUing hands 

 and shipboard skills of Ken Bliss, Bill Flerx, 

 Dennis Gruber, Sherri Hamer, Sue Longenotti, 

 Jack Metoyer, Patty Schmitt, and the most 

 excellent crew of RV David Starr Jordan. We 

 thank Jim DuFour of Scripps Institution of 

 Oceanography for providing the drifters, radio 

 tracking equipment, and tutorials. We thank 

 Rich Charter, Paul Fiedler, Larry Eber, Sherri 

 Hamer, Carol Kimbrell, Lee Inness-Brown, and 

 Pedro Paloma for technical support ashore. The 



paper also benefited from the comments of our 

 anonymous reviewers. 



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687 



