FISHERY BULLETIN: VOL. 73, NO. 1 



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NORTHERN MID-ATLANTIC 



BIGHT 



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TEMPERATURE 



Figure 16. — Index of abundance (geometric mean) of Raja senta captured in each subarea during winter 1969 within tempera- 

 ture intervals of 1°C. See Figure 3 for explanation of fractions and whole numbers. 



was found over almost the entire temperature 

 range in the Gulf of Maine and off southeastern 

 Nova Scotia. (Figures 20-22). 



INTERSPECIFIC RELATIONSHIPS 



Five of the species cooccurred significantly 

 writh one or more of the other species (Table 3). 

 Raja laeuis was associated with bothi?. erinacea 

 and/?, ocellata for half or more oi the Albatross IV 

 cruises. Raja erinacea andi?. ocellata cooccurred 

 significantly during all of the survey cruises 

 and were positively associated by abundance. 

 The product moment coefficients for the Albatross 



IV winter, summer, and autumn cruises of 1969 

 were: r = 0.656, 0.471, and 0.640. Percent of the 

 variation in j' associated with x was: 43%, 22%, 

 and 41% respectively. The slopes of all three 

 regressions were significant at the 1% probability 

 level. No reason was apparent for the low corre- 

 lation obtained during the summer cruise. Raja 

 senta and R. radiata had the highest coefficient 

 of association, and these two species were often 

 negatively associated with R. erinacea and R. 

 ocellata. Raja senta and R. radiata were not 

 correlated by numbers; the coefficients for the 

 Albatross IV winter, summer, and autumn cruises 

 of 1969 were: 0.310, 0.081, and 0.283. Only a 



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