ALASKA FISHERY AND FUR-SEAL INDUSTRIES, 1920. 95 



skins in a catch of 750 taken during the season of 191&-20, as against 15 white 

 pelts in a total 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 

 against 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 sucli marked foxes 

 are killed intentionally, and to avoid the possibility of such error it is a good 

 l)l;in t(» make the mark sutticiently plain to preclude any chance that the weigher 

 may not notice it. Light marks made early in the season may grow to be almost 

 indistinguishable before trapping stops. 



The blue fox of St. George Island is monogamous, and because of this fact 

 the sexes must be released in eipial 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 whieh 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 sudi 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 nnist 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 Miese factors, except as light has been thrown upon them l)y the growth 

 or decline of the lierd. From the pasr rate of growth we may assume a given 

 number of maturing .voung and a given death rate, both of which are subject to 

 an unknown correction of animals not caught, but such tigiu'es are somewhat 

 arbitrary and nuist be used with caution. We can not place dependence on the 

 uncertain hgm-e of the number of maturinir young or the unknown reserve of 

 animals not handled; the only reliable ligures are those from known* reserves, 

 and it is upon these we must base our policy. 



REIXDEKR. 



In August of 1911. 40 reindeer were bronjjht to the Prihilof 

 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 hulls were 

 hmded on St. Paul Ishind 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 throuofh lack of time 

 for attendinrr them, fairly accurate counts at the close of the calen- 

 dar year 1920 showed 192 deer on St. Paul Island and 125 on St. 

 (jQovge Island. The herds are becominjr regularly more valuable as 

 a meat supply, the number used for this purpose being larger each 

 vear. On St. Paul Island 22 reindeer were killed for food during 

 the calendar year 1920 and on St. George Island P>1 were so used. In 

 the i)revious 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 uj) 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 



