ANDERSON; A STOCHASTIC MODEL OF FISH SCHOOL SIZE 



comitant increase in (3 and decrease in a would 

 shift the probahility distribution towards a nar- 

 row range of small diameters. For example, if we 

 assume an increase in fishing activity off southern 

 California decreases a and increases fi by 50%, 

 then there would be a noticable decrease in the 

 occurrence of schools >20 m diameter (Figure 9). 



ACKNOWLEDGMENT 



I wish to thank Akira Okubo for his discussion 

 on this problem. 



LITERATURE CITED 



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1974. Stochastic models in biology. Acad. Press, N.Y., 

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Okubo. A.. W Sakamoto, t. Inagaki, and T Kuroki. 



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RADAKOV. D. V. 



197.3. Schooling in the ecology of fish. Wiley, N.Y., 173 p. 



SEREBROV, L. I. 



1976. Relationship between school density and size of 

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SHAW. E. 

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SMITH, P. E. 



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