COLTON: TEMPERATURE TRENDS AND GROUNDFISH DISTRIBUTION 



AMERICAN PLAICE 



CATCH PER TOW 



Di-io 



n 11-50 



 51-100 



 101-)- 



Figure 5. — Distribution of American plaice during October-November. 



designs were used, but for most cruises a strat- 

 ified random sampling technique was employed 

 in which station location and number were pro- 

 rated by area and depth zone. A complete 

 description of the sampling design currently 

 being employed is given by Grosslein (1969). 

 Although an -effort was made to standardize 

 sampling techniques, comparative tows made 



with the Albatross III and the Delatvare and the 

 Albatross IV and the Delaware showed that fish- 

 ing efficiency varied to some extent between ves- 

 sels and with towing methods (stern vs. side 

 trawling). Fishing efficiency also varies with 

 time of day and with species and age of fish 

 (Bigelow and Schroeder, 1953; Colton, 1965; 

 Fritz, 1965) . However, for the purpose of de- 



643 



