Table 15. — Selected and known-age yearlings tagged, St. Paul Island, 1961-63 



Tags within the range of numbers given were used. 



Table 16. — Number of seals selected for yearl- 

 ing tagging, by sex and rookery, St. Paul 

 Island, 1963 



[Number in parentheses indicate known-age yearlings; 



16 seals identified as yearlings by checkmarks and 



tag scars are included] 



3 and 4. The mean body lengths given in the 

 figures compare favorably with data from 1962. 

 Two known-age males exceeded the 100-cm. 

 maximum length established for the tagging of 

 selected yearling males. Two selected yearling 

 females longer than 95 cm. were tagged on the 

 basis of overall appearance. 



Body lengths of selected and known-age 

 yearling males and females are compared in 

 figure 5. Although the length distribution of 

 selected yearlings follows that of known-age 

 animals, especially for males, bias may exist 

 as a result of imposing maximum length 

 limits. 



LENGTH (CM.) 



LENGTH (CM.) 



Figure 4. — Length classes of 98 known-age yearlings, 

 St. Paul Island, 1963. 



LENGTH (CM) 



Figure 3. — Length classes of 701 selected yearlings, 

 St. Paul Island, 1963. 



Figure 5. — Comparison of length classes of selected and 

 known-age yearlings, St. Paul Island, 1963. 



The homing tendency of known-age yearlings 

 captured in 1963 is given in table 17 by 

 rookery. Sixty- eight percent of the yearlings 

 had returned to their "home" rookery. This 

 figure compares with 80 percent in 1962 and 

 75 percent in 1961. 



Pis cuss ion. --In 1963, yearlings were first 

 tagged on 19 September. This was probably a 

 week too early, since the availability of 

 yearlings increased markedly by 30 Septem- 

 ber. The fourth week in September appears 

 to be the optimum time to begin yearling tag- 

 ging. Yearlings apparently prefer to haul 



16 



