ALASKA FISHERY AND FUR-SEAL INDUSTRIES, 1920. 95 
skins in a catch of 750 taken during the season of 1919-20, as against 15 white 
pelts in a tetal of 486 secured in the season 1903-4. On St. Paul Island, where 
steel traps are being used and the selective killing is not carried on, 33 white 
animals appeared in a catch of 188 during the winter of 1919-20. The fight 
against white foxes on St. George Island has in recent years been extended 
gainst blue foxes which bear white marks of any kind. 
After the selection of the breeder it is marked by clipping the fur of the tail 
and is then released. This mark is a notch near the tip of the tail in the case 
of a male and near the middle of the tail for a female. No such marked foxes 
are killed intentionally, and to avoid the possibility of such error it is a good 
plan to make the mark sufficiently plain to preclude any chance that the weigher 
may not notice it. Light marks made early in the season may grow to be almost 
indistinguishabie before trapping stops. 
The blue fox of St. George Island is monogamous, and because of this fact 
the sexes must be released in equal numbers when the reserve is made. 
Size of reserve—The amount of food available during the winter months is 
the factor which controls the size to which the herd may be allowed to grow. 
The release of 200 pairs of breeding animals for a number of years past has 
provided a steady supply of skins, but this number must be gradually increased 
in proportion to the food supply if a sound policy of growth is to be carried 
out. During the season of 1919-20 a reserve of 225 pairs was made with a 
view to such a growth, and it is intended that the reserve be further increased 
each season that the food situation will allow. 
A consideration of the reserve naturally must bring in the factors of the 
number of young which reach maturity for each pair released and the percentage 
of natural mortality for all classes of foxes. It is to be deplored that we know 
little of these factors, except as light has been thrown upon them by the growth 
or decline of the herd. From the past rate of growth we may assume a given 
number of maturing young and a given death rate, both of which are subject to 
an unknown correction of animals not caught, but such figures are somewhat 
arbitrary and must be used with caution. We can not place dependence on the 
uncertain figure of the number of maturing young or the unknown reserve of 
animals not handled; the only reliable figures are those from known reserves, 
‘and it is upon these we must base our policy. 
REINDEER. 
In August of 1911, 40 reindeer were brought to the Pribilof 
Islands to determine whether these animals would thrive and even- 
tually provide a source of fresh meat for the Government employees 
and natives stationed there. Twenty-one cows and 4 bulls were 
landed on St. Paul Island and 12 cows and 3 bulls on St. George 
Island. 
The experiment has proved entirely successful. While the herds 
have become quite wild and difficult to handle through lack of time 
for attending them, fairly accurate counts at the close of the calen- 
dar year 1920 showed 192 deer on St. Paul Island and 125 on St. 
George Island. The herds are becoming regularly more valuable as 
a meat supply, the number used for this purpose being larger each 
year. On St. Paul Island 22 reindeer were killed for food during 
the calendar year 1920 and on St. George Island 31 were so used. In 
the previous year 14 on St. Paul and 22 on St. George were killed for 
food. 
SHIPMENTS OF FUR-SEAL AND FOX SKINS FROM PRIBILOF ISLANDS 
: IN 1920. 
Fur-seal skins —Three shipments of sealskins were made from the 
Pribilof Islands in the calendar year 1920. The first of these was 
made up of 900 skins in 47 casks from St. Paul Island and 412 skins 
in 11 casks from St. George Island, the number from the latter place 
being the entire remainder of the catch of 1919 on that island. The 
