Cage experiments in shallow water (3 m) confirm that polychaete recruitment occurs 

 slowly (probably via larval settlement), and that numbers of recruits are strongly 

 decreased by exposure to fish predation compared to controls (Reaka, unpub. data). 

 The remaining groups of major invertebrate taxa appear to be unaffected by fish 

 predators. Finer taxonomic resolution of these taxa (in progress) may yield 

 additional effects. It is also possible that a greater difference in predation 

 pressures between the A and C reefs would have shown a more pronounced effect. At 

 the moment, however, we conclude that the secretive habits of many of these cryptic 

 invertebrates protects them from pronounced effects of predators upon their popu- 

 lations at this study site. 



ACKNOWLEDGMENTS 



This work was supported by grants from the NOAA National Undersea Research 

 Program (NA80AAA03715, NA81AAA01500) and the National Science Foundation (0CE-78- 

 26605) to M.L. Reaka. In addition, we are grateful to Frank Pecora, Joseph 

 Landsteiner, Cheryl Van Zant, Jane Dominguez, David Moran, Hugh Reichardt, Joseph 

 Dineen, and Miriam Smyth for their assistance as either aquanauts or members of 

 the surface research team during our Hydrolab missions. We particularly thank the 

 Hydrolab staff for their support and cooperation throughout the study. This is 

 Contribution No. Ill from the West Indies Laboratory. 



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