PARSONS and TUCKER: FECUNDITY OF NORTHERN SHRIMP 



ST , MARYS BAY 

 MARCH I 97 \ 



ST. MARYS BAY 

 FEB. 1974 



see-l 

 20 

 2500- 



FORTUNE BAY 

 MARCH 1078 



FORTUNE BAY 

 MARCH 1 07O 



years were similar in slope but different in eleva- 

 tion (Fig. 4e). Average fecundity at length was 

 higher in 1978 than in 1982 in the latter area. 



Three comparisons were possible to detect differ- 

 ences between areas. In 1982, four areas were 

 sampled during September: Hudson Strait, North 

 Labrador Sea, Hopedale Channel, and Cartwright 

 Channel. Analysis of the data indicated no differ- 

 ence in the rate of increase in fecundity with increas- 

 ing size but a highly significant difference in the 

 mean number of eggs produced (Table 2, Fig. 5a). 

 T-Tests for sample means showed that the sample 

 from Hudson Strait was different from those taken 

 off the Labrador coast (Table 3). Fecundity in the 

 former was less at comparable sizes. 



Three areas were sampled in August and Septem- 

 ber 1978: east of Baffin Island (August), Hopedale 

 and Cartwright Channels (September). The data 

 from these samples also were similar in slope but 

 different in elevations (Table 2, Fig. 5b). T-tests 

 showed that the lower fecundity observed in the 

 Cartwright Channel was significantly different (a 

 = 0.05) from that observed in the other two areas 

 (Table 3). 



Two samples were taken off the south coast of 

 Newfoundland early in 1978: one from the south- 

 west coast in February and the other from Fortune 

 Bay in March. Eggs in both samples were "eyed", 

 indicating late stage development. The data showed 

 that average egg production was higher off the 

 southwest coast over the range of sizes compared 

 (Fig. 5c). The statistical analysis indicated similar- 

 ity in slopes but a highly significant difference in 

 elevations (Table 2). 



DISCUSSION 



Loss of eggs over the ovigerous period has been 

 reported in previous studies on fecundity of P. 

 borealis (Elliot 1970 3 ; Ito 1976; Skuladottir et al. 

 1978; Stickney and Perkins 1979; Stickney 1981). 

 This loss could be incidental or due to incomplete 

 fertilization and/or disease. Egg diameter also in- 

 creases between spawning and hatching (Haynes 

 and Wigley 1969; Ito 1976), and some eggs that are 



3 Elliot, D. L. 1970. Fecundity of the northern shrimp, Pan- 

 dalus borealis. Unpubl. manuscr., 32 p. Bowdoin University, 

 Brunswick, ME 04011. 



Figure 2.— Number of eggs (vertical axis) vs. carapace length in 

 mm (horizontal axis) for 15 samples of female northern shrimp 

 taken from areas of the northwest Atlantic. 



553 



