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Fishery Bulletin 92(2), 1994 



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AVALON PENINSULA LANDINGS 



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AW.ON PENINSULA EFFORT 

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BdHAVISTA SAY EFFORT 



YEAR 



Figure 2 



Summary of annual commercial landings and fishing effort for Chionoecetes opilio from 

 offshore Avalon Peninsula and Bonavista Bay, Newfoundland. 



fied by depth. Japanese-style conical traps baited 

 with approximately two kg of northern shortfin squid, 

 Illex illecebrosus , or with a mixture of squid and At- 

 lantic mackerel, Scomber scombrus, and set in 

 longline fleets of 12 were used to catch crabs. Al- 

 though an attempt was made to duplicate the meth- 

 odology employed by fishermen, space limitations 

 onboard the research vessels restricted fleets of traps 

 to 12 rather than the 50-70 used in commercial fish- 

 ing. Weather permitting, traps were hauled after a 

 24-hour soak. 



Crabs were removed from the traps, carapace 

 width (CW) measured to the nearest 1 mm and shell 

 condition determined. Three shell condition classes 

 were used, based upon the following criteria de- 

 scribed by Miller and O'Keefe (1981) and modified 

 by Taylor et al. (1989): 



Soft Shell (1) Carapace is brightly colored and free 

 of epibiotic growth. Ventrally the crab is off-white to 

 cream in color. Chelae bend, break, or crack with 

 slight pressure. Bright iridescence present on dorsal 

 margin of chelae. Animals within this category are 

 considered as having molted not more than 90 days 

 prior to capture. 



New/Hard (2) Carapace is duller in color and a num- 

 ber of tube worms are present. Shell is hard and ven- 

 trally may be dark-cream colored and covered with 

 discolored scratches. Chela does not bend or break 

 when moderate thumb pressure is applied. Irides- 

 cence on chelae is reduced in intensity. This category 

 generally applies to animals that have molted up to 

 two years prior to capture. 



Old/Hard (3) Carapace is dull brown in color and 

 an assortment of calcareous tube worms and bar- 

 nacles are present. The shell, although still hard, may 

 have a slight "leathery" feel. Ventrally, the shell is 

 brownish in color and many dark scratches evident. 

 Iridescence on chelae is faint or absent. This category 

 applies to animals that have not molted for at least 

 two years. 



Bottom temperatures from depths >170 m were 

 obtained from an oceanographic station (Station 27) 

 near the Avalon Peninsula fishing grounds (Fig. 1). 

 There is no oceanographic station in Bonavista Bay, 

 but bottom temperatures were obtained during 

 eight research cruises by using expendable bathyther- 

 mographs, or reversing thermometers. 



