
anyone realizes but are, year after year, postponing their tim of 
arrival on the breeding islands until after the sealing season. Many 
may even remain at sea during their entire bachelor life. As a result, 
the Government is harvesting a smaller percentage of the herd than it 
should, while at the same time the herd has actually reached a popula- 
tion of millions." If this were true, the harem-bull population would 
increase both in actual numbers and in proportion to the commercial kill, 
but it does not. The harem-buli count represented 20.3 percent of the 
group-III kill for the period 1931-35, 22.6 percent for the period 1936-48, 
and 20.5 percent for the period 1946-51 (tables 2 and 6). 
Escapement of bachelors from the kill 
The escapement includes all bachelors that live through their 
third and fourth years, the survivors eventually becoming the male 
breeding element of the herd. Escapement may be divided into two cate- 
gories: (1) Postseason escapement, including not only the bachelors 
that arrive on land after the killing season but also the fraction that 
may remain at sea; and (2) through-the-season escapement, including 
animals too large or too small to be selected in the kill. 
Field observations and tag returns show that the homing 
instinct becomes stronger with increasing age. Few yearling seals 
return to the Pribilofs, and those that do, arrive in the fall. Two- 
year-olds are distinctly juvenile and return in midsummer. Three-year- 
olds, also juvenile with few exceptions, return in early summer. The 
peak of arrival of succeeding age classes falls progressively earlier in 
the season, and the assumption appears justified that only the attendance 
of the juvenile classes on the Pribilofs is incomplete. Present indica- 
tions are that all 4-year males return to the breeding islands. The fact 
that the number of breeding bulls does not increase substantiates the 
assumption that most 3- and all 4-year males return to the breeding 
islands and are included in the escapement figures. There is no clear 
proof that on-the-ocean escapement is important, and it is convenient to 
include it under postseason escapement. The escapement of 3-year and 
4-year males from the kill is discussed in appendix E. On the basis of 
A-tag returns in 1950 and 1951 the following breakdown is obtained: 
Average escapement for 1950-52 of -- 
3-year males 4-year males 
Number Percent Number Percent 
Males killed ........ 38,046 60 21,478 19 
Through-the-season 
escapement . . . » « © 6 » 3,805 6 3,262 12 
Subtotal: males arriving 
on killing fields .. 41,851 66 24,740 91 
Postseason escapement ... 21,559 34 2,447 _9 
Total 63,4101/ 100 27,187 300 
e * * e * * s e . 3 
an - -_ -= - - 
1/ 3-year males alive at start of kill, excluding natural mortality 
during the summer, which is relatively unimportant. 
2/ 4-year males alive at start of kill. 
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