FISHERY BULLETIN: VOL. 80, NO. 2 



emphasize differences among individuals and 

 increase observed variability. 



The most plausible mechanism for explaining 

 low growth variability at Moolach Beach com- 

 bines limitation and removal processes. If the 

 population is food limited in the open ocean and 

 selective predation on smaller, slower growing 

 individuals is occurring, the observed variability 

 in size-at-age will be small. Using the otolith 

 aging technique this hypothesis is testable. It re- 

 quires a comparison of the size-at-age distribu- 

 tion of fish found in the stomachs of predators 

 with the distribution shown in Figure 3. 



A hypothesis arising from this study is that 

 survival, not growth, is enhanced in the estua- 

 rine nursery ground compared with the open 

 coast. Testing of this hypothesis will be an impor- 

 tant step in understanding the role that estuaries 

 play in the life history of many fishes. 



ACKNOWLEDGMENTS 



I would like to thank W. G. Pearcy, C. B. Miller, 

 and A. V. Tyler for their guidance and assist- 

 ance; B. Frey, E. Krygier, and C. Creech for pro- 

 viding accessory data; and J. L. Laroche and W. 

 Wakefield for their invaluable assistance 

 throughout the course of this study. 



Funding was provided by Oregon State Uni- 

 versity Sea Grant Project No. A/OPF-1. 



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