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ELECTROPHORETIC EVIDENCE OF 



HYBRID SNOW CRAB, 



CHIONOECETES BAIRDI X OPILIO 



Karinen and Hoopes (1971) and Hoopes et al. 

 (1972) reported finding snow (Tanner) crabs in the 

 southeastern Bering Sea which possessed mor- 

 phological characteristics that were atypical for 

 either Chionoecetes bairdi or C. opilio and, instead, 

 were intermediate. The females of this form 

 appeared to have reduced reproductivity, as many 

 were nongravid at maturity, and those that were 

 gravid possessed abnormally small egg clutches 

 containing large numbers of dead eggs. These 

 conditions were presented as evidence of hy- 

 bridization. Hybrid-type males constituted 1.0% of 

 all male snow crabs captured, while hybrid-type 

 females made up 0.4% of the females captured. 



Karinen (1974) confirmed the above reports and 

 found that hybrids made up 4.6% of the snow crabs 

 collected in the Bering Sea and were most abun- 

 dant west of lat. 166°W. The carapace width 

 frequency of the hybrids was intermediate 

 between C. bairdi and C. opilio-prowiding addi- 

 tional evidence of hybridization. 



The purpose of the present study was to deter- 

 mine if electrophoretic differences between the 

 parent species and the hybrid could be detected. 



The samples used were collected from the 

 southeastern Bering Sea in July 1974, identified, 

 and frozen by National Marine Fisheries Service 

 (NMFS) personnel. The general proteins of leg 



693 



