126 ALASKA FISHERIES AND FUR INDUSTRIES IN 1915. 
has killed and partly devoured two mates; and in another case the male killed and 
- ate the female. Regarding the latter instance, the pair had been corralled together 
before coming into our possession for three years, and during that time the female 
had killed two entire litters of pups when they were 2 months old. We know that 
this female was carelessly handled at a critical time, and that strangers were permitted 
to approach the nest when the pups were small, so that fact may account for her having 
turned cannibal. But for the male to have attacked his mate, after the two had been 
together in captivity for so long a time, is a thing we are unable to account for. These 
foxes were all having the best of care and attention, each was getting its full ration of 
food regularly, and they were all apparently contented. The first intimation our 
keeper had that anything was wrong was when he found the carcasses in the corrals. 
It is needless to say that the animals that committed these depredations will soon 
have their skins on the fur stretcher. 
A problem now facing us, and which might properly come under the head of ‘‘ Dis- 
position of foxes,’’ is the difficulty experienced by ranchers in rearing blue foxes in 
captivity. While but few attempts have as yet been made in Alaska in this direction, 
still the experiences of all have been about the same, and to date we know of no instance 
where a blue fox has been successfully raised to maturity in captivity on any of the 
ranches in Alaska. We have information of at least four litters of blue pups having 
been born, but in each instance they were destroyed by the parents before reaching 
an age of over 2 months. This must be attributable to some peculiarity in dispo- 
sition that is probably not possessed by the black fox, and therefore is a problem that 
must be worked out by patience and careful observation. 
The experience of some of the Canadian fox ranchers who exported blue foxes from 
Alaska two or three years ago has also been unsatisfactory, although it is reported that 
some have been successful in rearing a few pups, and one rancher reports having 
raised an entire litter of 12. We have also been told that the National Zoological 
Park, in Washington, succeeded in rearing at least two litters of blue-fox pups from 
parents taken from the Pribilof Islands. If this is a fact, some valuable information 
might be gained on the subject by an investigation of the manner in which the animals 
were handled. 
Aside from the difficulty experienced in rearing the pups, the animals seem to 
be disinclined to breed when in captivity. In the wild state, or when they are at 
liberty on island ranches, the blues are more prolific breeders than the blacks, but 
when confined they are certainly less inclined to increase than are the blacks. There 
must be some logical reason for this, and it is hoped that investigation will soon offer 
some solution to the problem. 
Since it has been proved that blue foxes will, even occasionally, breed and have 
young in captivity, then it seems unreasonable to believe that at least a few of such 
pups can not be raised to maturity. Time may show that only a small percentage 
of the blue foxes taken from islands, where they have had their liberty, willever 
breed when placed in confinement; but even so, we believe that by carefully propa- 
gating the few pups that might result from breeding these animals, and by eliminating 
from the breeding stock all barren foxes and those that might have a tendency to 
destroy their young, a good and prolific breeding stock can eventually be built up. 
All the experiments in this line that have come to our notice have been conducted un- 
der most unfavorable conditions, so the results of these trials really can not be accepted 
as a criterion as to the future possibilities in this business. 
We believe that the Government might well afford to investigate this subject and 
conduct experiments in breeding blue foxes in captivity. The Pribilof Islands, it 
seems to us, offer an excellent opportunity for this work, for an organization is now 
maintained there that could conduct such experiments along scientific lines. Fur- 
thermore, blue foxes are probably more numerous on these islands than any other 
place in the world, so breeding stock could be selected from a large number of animals. 
