Table 17. — Homing tendency of known-age yearling seals, by sex and rookery, St. Paul Island, 1963 



out to the rear of rookery areas, and also on 

 certain hauling grounds. The tagging program 

 and surveys in 1963 clearly established the 

 following areas as favorites for yearlings: 



(a) NEP - Sea lion Neck and Vostochni 

 Rookery 



(b) REEF - Above Castle Rock 



(c) TOL. - Eastern end and the area around 

 rocks 15-16 



(d) ZAP-REEF - Hauling ground and rookery 



(e) ZAP - Area from rock 17 to rock 23 



On several occasions, yearlings were seen 

 along the shoreline with seals of other ages. 

 They could not be captured because they 

 escaped into the sea. 



Because too frequent driving of the hauling 

 grounds and rookeries reduces the number 

 of yearlings available for capture, tagging 

 should be done on only 3 days each week (such 

 as Monday, Wednesday, and Friday). If yearling 

 surveys (see following section) are conducted 

 during the same period, tagging operations 

 should be reduced to 2 days a week. The best 

 areas can be completely covered in 1 day. 



The overall restrictions of rookery accessibil- 

 ity, yearling behavior, and limited time holds 

 the maximum number of yearlings obtainable 

 to about 150 per day, 300 per workweek, or 

 1,000-1,200 over a 5- or 6-week period. 

 Apparently 5,000 yearlings cannot be tagged 

 in one season. 



The tagging program has provided some 

 information on the movement of yearlings 

 about the island: Three tagged on Northeast 

 Point Rookery were recaptured 2, 12, and 28 

 days later at Zapadni Reef, Reef, and North- 

 east Point Rookeries, respectively; one tagged 

 on Kitovi Rookery was recaptured 3 days 

 later on Little Zapadni Rookery. Several 

 yearlings were recaptured 2 days later near 

 where they were tagged. Two of the known-age 

 yearlings given additional tags were re- 

 captured. 



Sex ratios among yearlings examined in 

 1941, * 1961, 5 1962, and 1963 are given in 

 table 18. The discrepancy between sex ratios 

 among selected yearlings was a result of the 



4 See footnote 2, page 15. 



5 See footnote 3, page 15. 



Table 18. — Sex ratios among selected and known-age yearlings, 

 St. Paul Island, Alaska, 1941 and 1961-63 



[Numbers in parentheses are the total numbers of males and females 

 from which the sex ratios were derived] 



17 



