94 U. S. BUREAU OF FISHERIES 
The comparative returns from these experiments were expected to 
show whether or not the additional period of pond rearing con- 
tributed materially to the resistance of fingerlings to disease and 
natural enemies. In another experiment, 10,000 fry from the Sky- 
komish station (on an independent stream system) were moved to 
the Samish station, where they were marked and lberated to deter- 
mine the effect of such transplantation upon the homing instinct. 
Although the returns will not be complete until the cessation of 
the spawning run in March, 222 marked fish were recovered during 
1936. Of these, 6 were from the 26,000 fish liberated in May at a 
length of approximately 46 mm (184 inches), 207 were from the 
26,000 fish liberated in November at a length of approximately 102 
mm (4 inches), and 9 were from the fish transferred from the 
Skykomish River and liberated in May at a length of approximately 
49 mm (2 inches). 
Recoveries were reduced by the loss of the hatchery rack on the 
Samish River during flood conditions shortly after the run began. 
This loss could not be repaired for a period of 2 weeks. A number 
of the marked fish which passed the rack during this time were re- 
covered in Friday Creek, and three others from the tributaries above 
Friday Creek. Accurate calculations of total returns to the river are 
thus impossible, but on the basis of recoveries to date, it is evident 
that the larger Samish fingerlings produced a return approximately 
35 times greater than did the smaller ones, and the Skykomish fish, 
although transplanted from a different river system, produced a 
return approximately four times better than did the smaller Samish 
fingerlings. 
Collections of scale samples and of length and weight data from 
the commercial fisheries were continued during the summer fishing 
season, but were seriously curtailed during the fall season when 
fishing was interrupted because of price disagreements between fisher- 
men and operators. These data were supplemented by collection 
from the sport fisheries. 
KARLUK RIVER RED SALMON 
Studies of the Karluk River red-salmon runs, which were begun 
in 1921, were continued during 1936 under the direction of J. T. 
Barnaby. Because it combines the advantages of being situated in 
the center of a large red-salmon producing area and of having its 
commercial fishery confined to the vicinity of the river mouth, Karluk 
River was selected for this long-term study of the ratio between 
spawning escapement and the return from that escapement, the fluc- 
tuations occurring in these ratios from year to year, and the causes for 
such fluctuations. These studies provide essential information on the 
number of salmon that should be permitted to escape the commercial 
fishery in order to provide a spawning reserve sufficient to maintain 
the fishery at a maximum level of productivity. 
A review of returns from the escapements during the period from 
1921 to 1928 shows no correction between the size of the escapement 
and the return; the smallest escapement yielded the largest return 
per spawning fish. (5.6 to 1), while the largest escapement yielded 
the smallest return (0.6 to 1). To determine what return may 
be expected from any given escapement, it 1s necessary to under- 
