Table 38. — Mean weight of untagged pups and 

 male return, Pribilof Islands, Alaska, year 

 classes 1957-59 



[Numbers in parentheses are the number of pups in each 

 sample] 



conducted 29 and 51 days after the first in 

 1962. A complete analysis of the 1962 and 

 1963 data was made by comparing the mean 



■weight of tagged and untagged pups by analysis 

 of variance where the numbers in the groups 

 (to be compared) were equal. The approxi- 

 mate method (Snedecor, 1956) using unweighted 

 means was used where the numbers in the 

 groups (to be compared) were unequal. The 

 comparisons were made within each of the 

 three groups of pups weighed in 1962. 



The results of the analysis showed that 

 tagged pups weighed less than untagged pups 

 (P<.01) for all three groups weighed in 1962 

 and for the single group weighed in 1963. The 

 effect of weight loss on survival of tagged 

 pups is unknown. 



The mean weight of tagged and untagged seal 

 pups are given in table 39 by rookery and by 

 sex for 1963 and in table 40 by sex for the 

 years 1957-63. 



The pups have been weighed approximately 

 1 week after tagging during the period 30 August 

 to 2 September. Appendix table 13 lists the 

 numbers and corresponding weights of tagged 

 pups by rookery and by sex. 



Table 39. --Mean seal pup weights, St. Paul Island, 1963 



Table 40. — Mean seal pup weights 1 approximately 1 week after tagging, St. Paul Island, 1957-63 



[In Kilograms] 



Group 



1957 



1958 



1959 



1960 



19b 1 



1962 



1963 



Males : 

 Tagged.. 



Untagged 



Females : 

 Tagged . . 



Untagged 



1 Numbers in parentheses are the number of pups in each sample. 



30 



