16 BULLETIN 1350, TJ. S. DEPAETMEKT OF AGRICULTURE. 
about the island, cost $15 to $25 each, depending upon the quality of 
lumber used and the labor. Feed cookers can be constructed or pur- 
chased at a cost of $15 to $50. Detention pens are necessary to con- 
fine foxes during short periods for various purposes, and can be 
built for $25 to $50. 
A good, substantial boat is needed to procure fish for feed, to feed 
the foxes, and to transport supplies to and from the mainland or 
other points. The location of the island, harbor facilities, and the 
quantity of supplies to be transported will help determine the kind 
of boat to be purchased. A motor boat used for short, light hauls 
Fig. 18. — A box trap used on some island fox ranches. The fox, feeding on the bait 
at the rear, pulls a wire which drops the entrance door. (Top removed and used 
to prop trap on side for showing interior wire) 
can be purchased for $600 to $1,000. A boat used for traversing 
long distances will cost $2,000 to $4,000. 
ESSENTIALS OF BREEDING 
Success in fox raising is directly dependent upon a careful and 
intelligent selection of the right type of breeding stock. Those 
engaged in the industry should have a clear conception of the im- 
portant factors involved in breeding. When the animals are con- 
fined in pens and the ancestry is known, selective breeding is a com- 
paratively simple matter. When the foxes run wild and breed 
promiscuously, however, as is the case on the islands of Alaska, it 
is impracticable to follow any definite system. In other words, the 
rancher is never quite sure that certain young foxes are the offspring 
of any particular pair of adults. Some ranchers, of course, may 
feel reasonably certain of the ancestry of one, two, or even three lit- 
