Sinclair et al.: Prey selection by Callorhmus ursinus 



151 



Percent number 



100 90 80 70 60 50 40 30 20 10 



10 20 30 40 50 60 70 80 90 100 



northern smoothtongue 



(Leurogkxsus Schmidt) 



gonatid squid 



(Gonatopsis borealis/ 

 Berryteu&tts magister) 



gonatid squid 

 (Gonatus madokairmiddendotlrl) 



walleye pollock (all ages) 

 (Theragra chalcogramma) 



Oceanic domain/Continental slope 



seals 



midwater trawls 



Continental shell (<200m) 



seals 



midwater trawls 



Figure 4 



Primary species identified in fur seal (Callorhinus ursinus) gastrointestinal tracts and midwater trawls col- 

 lected on and off the eastern Bering Sea continental shelf in 1985. 



walleye pollock 

 (Themgra chalcogramma) 



lanternfish 

 (Myaophxlae) 



northern smoothtongue 

 (Leuroglossus schmidti) 



gonatid squid 

 (Gonatidae) 



40 



60 



80 



100 





Q Marinovich midwater trawl 

  Diamond midwater trawl 



50 

 I 



100 



150 



200 



walleye pollock 

 (Theragra chalcogramma) 



yellowfin sole I 



jronectes asper) iMmnmu 



(Pleuronectes asper) 



rock sole 

 (Lepidopsena bilineala) I 



Pacific cod 

 (Gadus macrocephalus) 



Bottom trawls 

  1981 

 ^ 1982 

 □ 1985 



Mean CPUE values (no. /ha) 



Figure 5 



Catch per unit of effort (CPUE) number/hectare (no. /ha) values for species caught in 1985 

 midwater trawls and bottom trawls in 1981, 1982, and 1985. 



