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intense herb ivory. Without urchin 

 decrease by a factor of approx- 

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 on and preferences for certain 

 8). Differential effects on algal 

 ue to differences in grazing inten- 

 biomass removed). In this locality, 

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 bi omass algal community. In other 

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However, if fishes avoid some algal 

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reefs 

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gal comm 

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unities a 

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to all herbivore groups, the 

 bi vores may be masked. Spatially 

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 lgal communities with different 



and abun- 



117 



