Table 7. — Length and number of eggs in pink salmon at Olsen Bay, 1960-61 



879 to 2,346 eggs per female (average, 1,815 

 eggs) (table 7). The regression analysis with 

 the 50 fish indicated no relation between length 

 and number of eggs per fennale (r = 0.210). 

 This result may have been due to the relatively 

 small size range of pink salmon females at 

 Olsen Bay or to sampling more than a single 

 stock. 



Egg Counts in Relation to Size, 1961 



The 1961 females ranged from 41.1 to 50.3 

 cna. (average, 46.3 cm.) and contained 1,367 

 to 2,812 eggs per female (average, 2,094 eggs) 

 (table 7). The regression analysis indicated 

 a direct correlation between length and num- 

 ber of eggs for the 100 fish (r = 0.518) and for 

 the 50 fish taken between July 5 and 8 

 (r = 0.718). There was no relation between 

 length and number of eggs for the 50 fish 

 taken between August 17 and 19 (r =0.165). 

 Again, as in 1960, this result may have been 

 due to the relatively small size range of pink 

 salmon females in Olsen Bay or to sampling 

 more than a single stock. Foerster and 

 Pritchard (1941) found a positive correlation 

 between number of eggs and length but noted 

 that the correlation coefficients were lower 

 for pink than for sockeye salmon. They also 

 suggest the relatively small size range as a 

 partial explanation. 



Rounsefell (1957) tested the relation between 

 the average number of eggs in pink salmon 

 females and the summer sea temperature at 

 Ketchikan, Alaska, with a covariance analysis 

 using the data of Foerster and Pritchard 

 (1941). This analysis demonstrated a sig- 

 nificant negative correlation. Rounsefell con- 

 cluded that annual differences in nnean fecundity 

 of pink salmon are a function of sea tempera- 

 ture, which is the principal factor determining 

 average fish length. 



Egg Retention, 1960 



To determine the number of eggs retained 

 in the body cavity after spawning, 364 fennale 

 pink salmon were examined. Randonnly se- 

 lected fresh carcasses were examined be- 

 tween July 6 and August 3, and included fish 

 fronn both forks as well as the main stream 

 intertidal area. Carcasses were opened and an 

 estinnate made of the percent of eggs voided. 

 Of the females counted 317 (87 percent) had 

 voided virtually all eggs before death; 19 had 

 voided 75 percent; 7, 50 percent; 10, 25 per- 

 cent; and 11 had voided no eggs before death. 

 Using the 1,815 average number of eggs per 

 fennale in 1960, egg nnortality due to retention 

 was calculated to be approxinnately 7 percent. 



Egg Retention, 1961 



Between July 22 and September 8, 737 female 

 pink salnnon were exannined for egg retention. 

 Fresh carcasses, randomly selected at the 

 East and West Fork weirs and in the nnain 

 streann intertidal area, were exannined. Actual 

 counts of eggs were nnade for all but nine 

 fennales that had obviously retained all their 

 eggs. An average figure of 2,094 eggs was 

 used as a basis for calculating the percentage 

 of eggs retained. Egg retention was low dur- 

 ing July and August, announting to 2.7 percent 

 at the West Fork weir, 5.1 percent at the 

 East Fork weir, and 3.1 percent in the main 

 stream intertidal area (table 8), Egg retention 

 for the connbined July and August sannples 

 was only 3.8 percent. However, the 29 fennales 

 fronn the nnain streann intertidal area Septenn- 

 ber 8 and 9 had retained 41.5 percent of 

 their eggs. This retention was associated with 

 overcrowding and connpetition for redd areas 

 annong females during the peak runs of late 

 August and early Septennber. Length of stream 



20 



