Table 3. — Estimates of the effective mouth size of the pelagic trawl (PD based on estimated distance trawled 

 (speed X time), the catches of four lantemfishes, and the catches of four lantemfishes and volumes for IKMT's 

 on "paired" cruises. 



cover large nets from oceanographic vessels. We 

 need to compare catches of different-sized trawls, 

 however, in order to evaluate biases and to learn 

 what portions of the plankton-micronekton- 

 nekton spectrum are effectively sampled by dif- 

 ferent nets. 



Acknowledgments 



This research was supported by the Office of 

 Naval Research through Contract N00017-76-C- 

 0067 under Project NR083-102. I am grateful to 

 M. Willis, D. Stein, and R. Mesecar for comments 

 on the manuscript, to J. Fisher, F. Evans, and 

 D. Stein for invaluable help at sea, and to 

 G. Loverich for design and evaluation of the 

 pelagic trawl. 



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WILLIAM G. Pearcy 



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