REPORT OF THE COMMISSIONER OF FISHERIES. 105 
ALASKA FUR-SEAL SERVICE. 
SEAL HERD. 
The fur seals resorting to the Pribilof Islands, having enjoyed con- 
tinued immunity from indiscriminate killing at sea through the opera- 
tion of an international agreement, have increased in a manner that 
has justified optimistic predictions. 
The regular census of the herd taken in 1915, under the direction 
of G. Dallas Hanna, showed a noteworthy increase over 1914. The 
actual number of pups born was 103,527, as compared with 93,250 in 
1914, 92,269 in 1913, and 81,984 in 1912. The total number of seals 
computed to be in the herd was 363,872, as compared with 294,687 
in 1914, 268,305 in 1913, and 215,738 in 1912. ‘The classes of seals 
which are susceptible of actual enumeration are pups, harem bulls, 
and idle bulls. The number of breeding cows, since each gives birth 
to but one pup a season, is, of course, equal to the number of pups. 
The numbers of animals in the remaining classes must be obtained 
from estimates of death rates, fortified by incomplete counts, etc. 
In 1915, in view of the increased knowledge of the herd, the enumera- 
tor felt it desirable to change the percentages heretofore used in esti- 
mating the losses for the first three years of the seal’s life. This 
makes the total of the number of seals determined to be in the herd 
of 1915 not exactly comparable with the totals of previous censuses. 
The details of the 1915 count are as follows: 
RS 15 Sopot l.t tho ol uate ute 103, 527 | 3-year-old,males............---- 18, 282 
IBPASUINT COWS «~~ 1-0) oe = 103) 527 | 4-year-old males: - 2225.2: ..-- 3. 15, 848 
ren peillse 22s ce 3 as se 28 2,151 | 5-year-old males............-..- 11, 271 
enenneis ee Sete SESE cas. 2) 673 
Pe PRtE IE 51a eo) fos = yo) 4s se lan) 60, 613 PotalOwvEL GLI.B As Bs 363, 872 
PT 0) Ge a ee 47, 980 
In 1912, 5,228 pups of the season were branded on the Pribilof 
Islands. Subsequent observations made on these branded animals 
have been productive of valuable additional knowledge in regard to 
the natural history and growth of the seals. Some of these animals 
were observed in 1913, and in 1914 they were noted in large numbers. 
The number which returned in 1915 was so large, in comparison with 
the total number of seals under observation, as to indicate a lower 
mortality in the first three years of the seal’s life than had ordinarily 
been assumed. In 1915, from January 1 to August 10, inclusive, 53 
of these branded seals were killed on St. Paul Island and 49 on St. 
George Island, the skins of which were shipped to St. Louis that year. 
One hundred of these were graded in accordance with the London 
trade classification, with the following result: 
Bios eee one (bh 2.) ea. = peed ne Seen SUC SUS CSE eis o seins dina 7 
bia oi Til 12 Rae aa ee eae SM hs yt ae ORS SAE RES Pge Larios Los Biase 42 
Perea ie teeth IAA_ PO. SSE. SMI OER ..d i Lae Lash ae 42 
MIDI eae ose 2 ot 8 oh OF CUE. cor. 5 cri aba 3 js se - SEG ya sy San ts Geet ep sree 8 
EAC TINS 8 AEE Sear Po te Se Ee Es oh cE PN ae a oe 1 
POUmer seers = UU aekte ts AN SLE Ok IL BORA S, AG AG. 100 
At the same time the skins of 15 of 18 branded seals killed in 1914, 
and therefore 2 years old, were graded as follows, the remaining 3 
not being accessible at the time: 
mere ging ld WUps: jie ated. esis chivd ies | deere ee cee Saige -Gckh Hiseiedinetectewc 3 
SHBAIE UDA se aes fe oma olen arin Chie am sala bac eis iaind = einiebin Fis jan olnfatninie'n bin a = 8 
A MDG ee Sse heat aicalnln vehinis gcse podsenseetaeacesatucwer= >= 4 
