58 ' "_-y, §, BUREAU OF FISHERIES. 
MANCHESTER (IOWA) STATION. 
[Frank E. Hare, Superintendent.] 
The output of this station consists of 125,500 eyed eggs of the rain- 
bow trout and 678,585 fry and fingerling fish of the different species 
propagated. The rainbow-trout brood stock did not yield an alto- 
gether satisfactory return, there being only 378,600 eggs taken. With. 
the maturity of plans now being formulated a very decided improve- 
ment in this direction is confidently expected. During the spring 
25,000 eggs taken from wild rainbow trout were transferred to Man- 
chester from the bureau’s Montana station with the view of infusing 
new blood in the brood stock, and the product of an equal number of 
steelhead eggs shipped from the Birdsview (Wash.) station will also 
be reared with that end in view. The adult brook trout, consisting 
of 625 2-year-old fish and 35 fish 8 years old and over, yielded 58,000 
eggs. These fish were again affected by a gill disease just prior to the ~ 
spawning season and suffered a heavy mortality. Brook-trout eggs 
to the number of 550,000 were obtained from commercial dealers in 
Massachusetts and incubated with satisfactory results. The cold 
weather of the late spring reduced the output of largemouth black 
bass to 2,500 fingerlings, but better success attended the culture of 
the rock bass, the distribution of that species amounting to 53,910 
No. 14 fingerlings. 
NEOSHO (MO.) STATION. 
[Frep J. Foster, Superintendent. ] 
There was a very satisfactory increase in the output of rainbow 
trout from this station for the fiscal year 1921. The records indicate 
that the egg shipments were increased over those of the preceding 
year by 48 per cent, while the increase in the number of fingerling 
fish distributed was as high as 117 per cent. The improvement was 
not confined solely to the increased number of fish and eggs produced 
but has been extended to the quality of the product and a betterment 
of the condition of the brood stock. 
For a number of years the station has been supplied with water 
from two sources—the Hearell Spring and the McMahon Reservoir. 
Observations made by the superintendent led to the belief that the 
eges of fish held in ponds supplied from the spring were not equal, 
either in numbers or quality, to those taken from fish in ponds sup- 
pled from the reservoir. For the purpose of testing the soundness 
of this theory the following experiment was conducted: A number 
of 3-year-old rainbow trout from the same hatch, which up to the 
time of the experiment had been held in the same pond, were divided 
into two equal lots. One lot was placed in pond No. 18; supplied 
entirely with water from the McMahon Reservoir, and the other was 
placed in Pond F, supplied largely from Hearell Spring. The eggs 
obtained from fish held in the McMahon water proved 82 per cent 
