BEARDSLEY: DESIGN AND EVALUATION OF A SAMPLER 



west Fisheries Center, National Marine Fisher- 

 ies Service, NOAA, Kodiak, Alaska, pers. 

 comm.) Biologists from the Fish Commission 

 of Oregon (Jack G. Robinson, per. comm.) now 

 insert a modified sampler, 2 ft wide by 9 ft tall, 

 in the mouth of a conventional 41-ft Gulf shrimp 

 trawl to achieve estimates of trawl efficiency. 



ACKNOWLEDGMENTS 



The enthusiastic support and advice of Rich- 

 ard M. McNeeley, Manager of the Conservation 

 Engineering Program in the Division of Marine 

 Fish and Shellfish, Northwest Fisheries Center, 

 Seattle, Wash., are gratefully acknowledged. 

 Donald D. Worlund, Division of Fisheries Data 

 and Management Systems, Northwest Fisheries 

 Center, Seattle, helped in the statistical evalu- 

 ation. I also thank Robert P. Larsen, Skipper, 

 and the crew of the NMFS research vessel John 

 N. Cobb and Olaf Engel, Skipper of the chartered 

 vessel Baron, for aid in the collection of shrimp 

 samples. 



LITERATURE CITED 



Abramson, N. J. 



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RiCKER, W. E. 



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253 



