310 REPORT OF THE SECRETARY OF THE INTERIOR 
selves remains the principal function in which effectiveness can be 
increased. 
At the close of the year the Bureau assumed responsibility for a 
trout hatchery and rearing unit constructed by the Forest Service 
on Warm River, Idaho. The site is considered one of the best in 
the Western United States. A few Dolly Varden trout were propa- 
gated, although its low esteem by the anglers discourages any general 
attempt to increase its abundance. Efforts of several years duration 
to establish the smallmouth bass in the Southwest appear to have 
been crowned with success, although additional time will be required 
for the species to become abundant. The Bureau has continued to 
experience a shortage of Loch Leven trout, following the virtual 
elimination of the egg supply previously obtained from the Madison 
River in Montana. Substitution of a domesticated brown trout stock 
has been resorted to as a means of overcoming the deficiency. One 
of the railway distribution cars was retired from service during the | 
year, since the fleet of distribution trucks has been built up to a 
point where transportation by highway largely supplants movement 
by rail. 
A new demand for warm-water fish has developed as a result of 
the program of farm pond construction sponsored by the Soil Con- 
servation Service. Although these requirements and the demands 
for stocking other waters under direct Federal control have been 
given priority, the percentage of unfilled applications from private 
individuals and organizations has remained at a low level. 
Shipments of rainbow trout eggs were made to Puerto Rico, 
Hawaii, and to the Republic of Colombia. A successful hatching 
season during the winter and spring provided an excellent stock of 
young fish which were being held for rearing and subsequent dis- 
tribution at most of the stations at the close of the year. 
Upper Mississippi Wildlife and Fish Refuge—The traditional 
salvage or rescue of stranded fishes in the overflow areas was vir- 
tually terminated. The Bureauw’s policy of constructing propagating 
ponds at suitable points within the refuge was fully justified by the 
production achieved at Genoa, Wis., Guttenberg, Iowa, and several 
other points. The yield of bass was so great during the summer of 
1939 that distribution facilities were taxed to the limit. The 1940 
hatch was not as heavy, but the production was of great value in 
maintaining the supply of fish in the great recreational areas in 
Minnesota and Wisconsin. In addition to this type of fish-cultural 
work, the headquarters station at LaCrosse, Wis., also provided a 
large quantity of trout for the same areas. 
