MARKING 



Pups 



Single T- series tags were attached to the 

 right front flippers of 9,980 pups on St. Paul 

 Island and 2,492 pups on St. George Island. 

 The tip of the same flipper was removed as a 

 checkmark. 



One hundred fifteen pups on St. Paul Island 

 were experimentally marked by freeze-brand- 

 ing the letter "T" on their forearms. An ex- 

 posure of 10 seconds gave good results. 



Yearling Male Seals 



Double IT- series tags were attached to the 

 front flippers of 835 males selected as year- 

 lings on St. Paul Island. 



Male Seals Ages 2 to 4 



Double 2T-series tags were attached to the 

 front flippers of 1,220 males in ages 2 to 4 on 

 St. Paul Island. 



RECOVERIES 



Tags, Checkmarks, and Marks 



Recoveries of seals marked as pups on the 

 Pribilof Islands included 2,764 with tags, 1,368 

 with checkmarks, and 175 that had been 

 marked but not tagged. Thirty-one seals tagged 

 as pups by the U.S.S.R. were killed on the 

 Pribilof Islands in 1967, and 364 seals tagged 

 as yearlings and 764 tagged at ages 2 to 4 on 

 St. Paul Island were recovered. An additional 

 261 seals that had lost two tags were taken. 



Tag Loss 



Among seals tagged as pups, the rate of tag 

 loss observed on St. George Island was less' 

 than that for St. Paul Island for Q-, P-, and 

 O-series tags. The rate of loss for R-series 

 tags was about twice that for Q- and P-series 

 tags. 



The probability of loss for tags applied to 

 seals at age 1 was 0.25 during the first year 

 following application for IS- series tags and 



0.39 in 2 years for lR-series tags. There was 

 a loss of 0.30 in 1 year for 2S-series tags. 



Time of Tagging 



Tags applied to pups in September of 1963 

 and 1964 have since been recovered at a sig- 

 nificantly higher rate than tags applied to pups 

 in August of the same years. 



POPULATION ESTIMATES 



Number of Pups Born 



On the basis of tag recoveries, the estimated 

 number of pups born on the Pribilof Islands has 

 steadily decreased from 643,000 in 1960 

 to 377,000 in 1965. 



On the basis of shearing and sampling live 

 pups on Reef and Tolstoi Rookeries for marked- 

 to-unmarked ratios, the number of pups born 

 on the Pribilof Islands in 1967 was about equal 

 to the estimated 385,000 pups born in 1966. 



Number of Yearling Male Seals 



On the basis of recoveries of male seals 

 tagged as yearlings, the Pribilof Islands had 

 an estimated 79,000 yearling males in 1963, 

 and 129,000 in 1965. 



FORECAST OF THE KILL OF MALE SEALS 



The predicted kill of males on the Pribilof 

 Islands by 5 August 1967 was 4,000 of ages 2 

 and 5, 34,300 of age 3, and 17,900 of age 4. 

 Actual kills were 4,619 of ages 2 and 5, 

 34,613 of age 3, and 15,523 of age 4. 



The predicted kill of males on the Pribilof 

 Islands by 5 August in 1968 is 4,500 of ages 2 

 and 5, 28,000 of age 3, and 17,000 of age 4. 



SPECIAL STUDY: NUTRITION OF PUPS 



Pups fed a formula without supplemental 

 selenium, vitamin E, methionine, and glycerin 

 lost weight and died within about 2 weeks; pups 

 fed the supplement gained weight and were 

 considered suitable for use in a disease sus- 

 ceptibility experiment. 



ACKNOWLEDGMENTS 



The research program in 1967 was completed 

 with the cooperation of C. Howard Baltzo, Pro- 

 gram Director; Bertel W. Johnson, Manage- 

 ment Staff Officer; Richard A. Hajny, Wildlife 

 Management Biologist; Harold Thayer, Pro- 

 gram Construction Supervisor; Victor Misiken, 



Sealer III Foreman; Alex Melovidov, Sealer I 

 Foreman; Lee Paola, Superintendent, Oregon- 

 Alaska Marine Products; and Iliodor Mercu- 

 lief, President, St. Paul Island Community 

 Council. 



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