PROGRESS IN BIOLOGICAL INQUIRIES, 1956 51 
E. W. Surber. Collections of bottom samples at several stations in 
St. Marys River and Kennedy Creek were made at monthly inter- 
vals, and data on all trout taken from these streams during the 
season were collected by the Forest Service. ‘The primary purpose 
of the study is to obtain as complete information as possible on the 
results of artificial stocking. 
Big Spring Creek, Va. ~The trout production studies on Big 
Spring Creek near Leesburg, Va., were continued for the fourth con- 
secutive year. The 1-mile section produced 30.2 pounds of trout per 
acre as compared with 29.7 in 1933, 27.7 in 1934, and 34.8 in 1935. 
Such uniformity in results over the 4- -year period was unexpected 
and is the more remarkable because the stocking intensity was 
doubled in 1935, apparently without effect on production in 1936. 
It should be explained that trout grow very rapidly in this stream 
and practically all fish planted reach catchabie size the following 
year. 
Pisgah Forest project—Through a cooperative agreement with 
the United States Forest Service “arrangements have been made to 
utilize a streams of the Pisgah Division of the Pisgah National 
Forest, C., as an experimental and demonstration project of the 
value me scientific stream management as a means of improving 
angling conditions. The Forest “Service has constructed a rearing 
station on the headwaters of the Davidson River -which will be 
operated by the Bureau. In addition to rearing pools of various 
sizes, the station is provided with a residence, workshop, and labora- 
tory. It is believed that this arrangement will provide an excel- 
lent opportunity for acquiring information essential to the dev elop- 
ment of afish-management policy for streams of the southern 
Appalachian region. 
Feeding exper eriments.—Owi ing to lack of funds, feeding experi- 
ments have been greatly curtailed during the past 3. or 4 years. 
However, several experiments were conducted at the Leetown hatch- 
ery with diets containing seal meal, salmon meal, preserved had- 
dock, and “salmana.” The chief interest in these diets centers around 
the use of seal meal because of its availability at low cost. This diet 
had previously given good results over a 3-month period but a du- 
plicate experiment continued for a longer time resulted in heavy 
mortality, confirming results at other hatcheries where this product 
was fed for a considerable length of time. 
Breeding experiments.—F itty pairs of selected brook trout were 
mated at the Pittsford hatchery and the eggs incubated in individual 
lots. As usual, the better lots were reared separately through the 
summer. It is noticeable that the losses among selected fish from 
furunculosis have been decreasing each year and it is believed that 
a more resistant strain of trout is gradually being developed. 
Similar experiments with brown and rainbow trout are being car- 
ried on at the Leetown hatchery. 
Leperiments with acalelr, eggs.—In an effort to determine the 
cause of the heavy losses suffered by brook trout eggs at the Leetown 
hatchery, duplicate lots of brook and rainbow eggs were incubated 
under varying conditions by EK. W. Surber. Variations in the highly 
mineralized hatchery water were produced by adding very small 
quantities of iodine, by reducing the normal high free carbon dioxide 
