sampling also precluded routine sharing of water 

 samples with others whose programs were de- 

 signed around standard depths, and, with the pre- 

 sent high cost of ship time, the pressure for shar- 

 ing samples is often considerable. Indeed, this 

 study was possible primarily because there was an 

 unusual amount of excess wire time available. 



On the other hand, there were advantages to SR 

 quite apart from the general merriment caused by 

 the unorthodox bottle spacing. The results from 

 the occasional closely spaced samples gave con- 

 tinual insight into the vagueries of small-scale 

 vertical stratification. For instance, within the top 

 30 m, samples separated by 1- and 2-m intervals 

 differed by <3% of their mean. In the region of the 

 chlorophyll maximum, between 75 and 125 m, the 

 same intervals produced deviations of 30% and 

 40%, indicating sharp layers and frequent inver- 

 sions. 



It is not within the scope of this paper to make 

 generalizations concerning the use of systematic 

 sampling versus SR. The potential advantages 

 and disadvantages of each have been dem- 

 onstrated in one environment. It is the responsi- 

 bility of all researchers to evaluate the use of RSS 

 in reference to their specific programs. If a poten- 

 tial problem is recognized, it is hoped that it will 

 stimulate a preliminary sampling study to 

 examine directly the consequences of RSS in the 

 biological system of interest. This worker's ex- 

 perience with SR was satisfactory, and the poten- 

 tial for biased data is sufficiently undesirable that 

 effort will be made to incorporate randomization 

 into future sampling designs. It is hoped that the 

 untidy profiles which will result will be accepted 

 with understanding by the scientific community. 



ACKNOWLEDGMENTS 



This work was supported in part by the Office of 

 Naval Research Grant N00014-75-C-0152, and in 

 part by the Marine Life Research Program, the 

 Scripps Institution of Oceanography's part of the 

 California Cooperative Oceanic Fisheries Investi- 

 gations, which are sponsored by the Marine Re- 

 search Committee of the State of California, and 

 by the National Science Foundation Grant GB- 

 286L 



Michael M. Mullin and Thomas Hayward criti- 

 cally reviewed the manuscript. Special thanks are 

 due to Hayward for unfaltering cheer and en- 

 thusiasm and occasional well-needed prompting 

 during 0300 chlorophyll casts. 



FISHERY BULLETIN VOL 76. NO. 3 



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