55-59 65-69 75-79 85-89 95-99 105-109 115-119 125-129 135-139 



60-64 70-74 80-84 90-94 100-104 110-114 120-124 130-134 140-144 



CARAPACE WIDTH (5 mm GROUPS) 



Figure 1.— Size-frequency distributions of male and female Chionoecetes opilio collected as pairs in 

 Bonne Bay, Newfoundland, during April-May 1984. 



of new eggs were found over the entire sampling 

 period. 



Females were observed with spermathecae con- 

 taining both old and new spermatophores. In these, 

 spermathecae were engorged with a very white 

 glutinous material containing new spermatophores 

 for three-fourths of their length, while the remain- 

 ing one-fourth at the dorsal end of the organ was 

 shrunken and contained a yellowish brown 

 substance of a "waxy" consistency. Females which 

 did not have new spermatophores had very small 

 spermathecae which were entirely yellowish brown 

 in color. This is very similar to that described for 

 Chionoecetes bairdi by Paul (1982). While 97% of all 

 females examined contained old spermatophores, 

 those containing new spermatophores as well in- 

 creased to 92.9% from 48.6% between 24 April and 

 25 May (Table 2). Two specimens contained new 

 spermatophores only and all had old epizooite- 

 encrusted shells. Thirty-six percent of the females 



with new spermatophores carried full clutches of 

 eyed eggs. 



Diving during 28-31 May revealed that all crabs 

 had left the sampling area. 



Discussion 



Small numbers of grasping, male/female pairs of 

 C. opilio and C. bairdi have been observed in shallow 

 water elsewhere. Ennis (Unpubl. data) found five 

 pairs and Hooper (Unpubl. data) found three pairs 

 of C. opilio in Bonavista Bay and Placentia Bay, 

 Newfoundland, respectively. Donaldson (1975) 

 reported two pairs of C. bairdi in Alaska. However, 

 nothing comparable with the magnitude of the 

 breeding migration of C. opilio, observed in Bonne 

 Bay, Newfoundland, has been reported for other 

 areas. There is considerable scope for speculation 

 on the ecological significance of this migration. 

 Although about half the females examined just prior 



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