164 U. S. BUREAU OF FISHERIES 
A shortage of bulls will cause a reduction in the yearly rate of 
increase of pups. A larger number of surplus bulls can do no 
harm, except to make it a little more difficult to drive. If previous 
experience in reserving should be repeated, the increases of killable 
seals secured through making extra reserves would more than pay for 
itself within the next 5 years. . 
The albino bull, first observed in 1935, frequented the idle-bull area 
back of Reef rookery the greater part of the season. At no time was — 
he observed with any cows. 
AVERAGE HAREM 
The average harem is computed from the estimated number of cows — 
and harem bulls. This year’s figures indicate an increase in the aver- 
age harem from 43.43 in 1937 to 46.69 in 1938. This increase should : 
not cause any great concern, although a lower average harem would — 
be preferable, as it would show that there were more than sufficient — 
It is felt that the more bulls there are on hand the faster the herd 
will increase. An extra large number of bulls does not now necessarily 
create a much smaller average harem. It would mean that as the” 
season advances and the harem bulls become exhausted, or at least 
weaker, their places would be taken by stronger bulls not worn out 
from harem duties. The present system does not provide for any 
considerable replacement of harem bulls during the active breeding 
season. 
Computation of breeding cows, based on annual increase of 8 percent, and of average 
harem, in 1938 


Breeding cows Average harem 

Rookery bulk, G 





Bi yo be 
be of 
ak 
Py 8 
# 
oy 
8 Re 
oy 
bet 
By 
n 
i t 
a 
war 
\- 
re 
M4 
i 
a8 
