FISHERY BULLETIN: VOL. 83, NO. 4 



METHODS 



Georges Bank, a large, submerged, marine plateau, 

 is located off the northeastern coast of the United 

 States (Fig. 1). It has been the site of an intense 

 fishery for several centuries, and a large interna- 

 tional fleet exploited the area from the 1960's to the 

 mid-1970's. The NEFC has conducted annual bot- 

 tom trawl surveys on the Northwest Atlantic con- 

 tinental shelf since the autumn of 1963. Annual 

 spring surveys commenced in 1968 and, in addition, 

 several summer and winter cruises have been under- 

 taken on an intermittent basis. Surveys were con- 

 ducted from Nova Scotia to Hudson Canyon from 

 1963 to 1966 and coverage was extended to Cape 

 Hatteras beginning in 1967. Grosslein (1969) and 

 Azarovitz (1982) described the details and justifica- 



tion for the surveys, but a brief summary is 

 appropriate 



The objective of the surveys is to obtain statistical- 

 ly meaningful abundance estimates of the offshore 

 marine fish populations in the aforementioned areas. 

 Secondary objectives included the collection of data 

 for distribution studies, age and growth determina- 

 tions, predator-prey interactions, and a host of 

 special purpose investigations. The potential area 

 was divided into zones (strata) based on depth and 

 biological considerations. Stratified random samples 

 were selected with allocation to each strata propor- 

 tional to its area. A 30-min sample with a standar- 

 dized research bottom trawl and a 1.25 cm cod end 

 liner was accomplished. All fish, as well as major in- 

 vertebrates, were sorted to species, weighed, and 

 measured, and some fish were sampled for other 



MAINE 



44' 



42° 



40" 



74' 



72* 



70' 



68' 



66° 



64" 



Figure 1.— Georges Bank and Gulf of Maine region with shoreline place names and other associated geographical landmarks. 



508 



