SUMMARY 



AGE CLASSIFICATION AND NUMBER OF 

 SEALS KILLED, BY SEX 



Males 



Of 52,497 male seals killed on the Pribilof 

 Islands in 1966, 42,104 were taken on St. Paul 

 Island and 10,393 on St. George Island. Male 

 seals from 42 inches (106.7 cn-i.), tip of nose 

 to tip of tail, up to but not including those 

 having a mane were killed. 



Females 



The kill of female seals on the Pribilof 

 Islands in 1966 was 391, including 61 taken 

 for research and 330 killed accidentally during 

 the kill of males. 



MARKING 



Pups 



SURVEY DATA 



Mortality 



Pups .-- The count of dead pups on the 

 Pribilof Islands was 27,392. 



The major causes of death among 164 pups 

 collected through the season in 1966 were 

 apparent malnutrition (42 percent), hookworm 

 disease (18 percent), infections (10 percent), 

 and bite wounds (9 percent). Miscellaneous 

 and undetermined causes of death accounted 

 for 15 percent; 6 percent of the pups collected 

 were not examined because of deconnposition. 



Adults . --On St. Paul Island the number of 

 dead adult seals counted was 158 males in 

 1965 (females were not counted) and 181 

 males and 172 females in 1966. On St. George 

 Island, 41 males and 55 females were counted 

 in 1966. 



Counts of Living Adult Males 



Harem nnales coionted on the Pribilof Islands 

 in mid-July of 1966 decreased for the fifth 

 consecutive year, to 71 percent of the number 

 counted in 1961; idle males equaled 47 per- 

 cent of the count in 1961. 



Reproductive Condition of Females 



Of the 65 3-year-old females exan-iined, 

 none had ever been gravid. One of the 51 

 4-year-olds was primiparous and recently 

 postpartum. 



Weights of Pups 



An experiment in 1966 indicated that handl- 

 ing causes pups to lose weight or retards 

 their growth. 



Single S-series tags were attached to the 

 right front flippers of 10,000 pups on St. Paul 

 Island, and the tip of the second digit of the 

 right hind flipper was removed as a check- 

 nnark. On St. George Island, single S-series 

 tags were attached to the left front flipper of 

 2,499 pups and the tip of the same flipper was 

 removed as a checkmark. 



Small numbers of pups have been marked 

 experimentally since 1963 with coded wire, 

 plastic roto tags, button ear tags, "spaghetti" 

 tags, snaall cattle-ear tags, and butt-end leg 

 bands. Additional pups have been marked by 

 cryogenic ("freeze") branding. In 1966, 9,578 

 pups on St. Paul Island were nnarked by re- 

 moving the tip of the third digit of the right 

 hind flipper and 2,503 on St. George Island 

 were marked by removing the tip of the 

 second digit of the left hind flipper. 



Male Yearlings 



Double IS-series tags were attached to the 

 front flippers of 1,495 males selected as 

 yearlings. 



Males Ages 2 to 4 



Double 2S- series tags were attached to the 

 front flippers of 1,483 males selected as 2-, 

 3-, and 4-year-olds. 



TAG RECOVERIES 



Recoveries of seals on the Pribilof Islands 

 included 4,418 marked as pups--2,685 with 

 tags and 1,733 with checkmarks--and 159 

 males tagged as yearlings on St. Paul Island 

 in previous years. A total of 30 Soviet-tagged 

 seals were killed- -28 of Commander Islands 

 origin and 2 from Robben Island. 



Recoveries of tags since 1954 have shown 

 that the tendency of fur seals to return to 

 their rookery of birth increases as the animals 

 become older, that homing tendency is more 

 pronounced for seals born on St. Paul Island 

 than for those born on St. George Island, and 

 that seals from some rookeries have higher 

 rates of homing than do seals from other 

 rookeries. 



To test the possibility that older pups nnay 

 survive the effects of tagging better than pups 

 tagged earlier in summer, one group of pups 

 was tagged in mid-August and another in late 

 September in each of 2 years (1963 and 1964). 

 Data collected in 1966 indicated a higher rate 

 of recovery from the late than from the early 

 group. 



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