' PROPAGATION AND DISTRIBUTION OP POOD PISHES, 192 8 381 



caused by the new road, it will be necessary to make further changes and 

 particularly to build a concrete basin for retaining the water before the trouble 

 can be eliminated completely. 



Over 1,000,000 rainbow-trout eggs were taken from the station brood stock 

 between the months of November and February. Two lots of brown-trout eggs 

 were incubated at the station for private parties. All brook-trout eggs handled 

 were purchased from commercial dealers, and an average number of fingerlings 

 was produced. The output of rainbow trout was considerably larger than 

 usual. With regard to the production of pond fish, heavy rains retarded the 

 distribution and probably cut down the output. Approximately 34,000 fry and 

 fingerling largemouth bass were distributed, and it is estimated that about 

 20,000 remained in the ponds at the close of the year. An average production of 

 rock bass and sunfish is expected. The station cooperated with other depart- 

 ments of the Government by furnishing large numbers of tadpoles to the 

 Chemical Warfare Service at Edgewood, Md., and to the Pharmacological Service 

 in Washington, D. C. 



Manchester (Iowa) Station 



(G. n. Gill, Superintendent) 



Over twice the number of rainbow-trout eggs that were secured in the previous 

 year were taken from the station brood stock this season. A particularly inter- 

 esting occurrence was the production of a large number of eggs of the highest 

 quality by the 2y2-year-old trout. Operations with the smallmouth black bass 

 and other pond species were not very successful. During the year 785,000 brook- 

 trout eggs were procured from commercial hatcheries, but an epidemic of gill dis- 

 ease occurred among the resulting fingerlings. At the close of the year approxi- 

 mately 100,000 rainbow-trout fingerlings and 235,000' brook-trout fingerlings wei-e 

 on hand. The ponds for the warm-water fishes were lined during the season, 

 and four new metal hatching troughs were added to the station equipment. 

 Considerable work was accomplished in the construction of cement walks, steps, 

 etc., and the pond system was improved by the construction of dikes and the 

 building of cement supply cribs and outlets. 



Neosho (Mo.) Station and Substation ' 



(W. H. Thomas, Superintendent) 



In December a special appropriation became available for making improve- 

 ments to the Neosho station. The superintendent's residence was repaired 

 extensively both inside and outside ; the house was rewired and the interior 

 refinished. Improvements were made to the annex building, also. The grounds 

 were beautified by planting trees and flowers, the entrance approach was 

 widened, and new concrete walks were constructed where needed. A diminution 

 in the spring-water supply is ascribed to the clogging of the line with sediment. 

 Some diflaculty has been experienced with the drain lines from the ponds. 

 Extensive improvements were made to the pond system. 



The rainbow-trout brood stock was segregatde according to age, and it was 

 found that eggs from the younger fish were of much better quality than the 

 others. All rainbow brood stock over the age of 3 years was planted. Infection 

 with the parasite gyrodactylus gave rise to considerable trouble among the 

 fingerlings, but treatment served to bring it under control. The station dis- 

 tributed about 233,000 rainbow and Loch Leven fingerlings and handled sev- 

 eral million eggs from the station brood stock and from Bourbon substation. 

 There was a continuation of the difficulty arising through seepage from the 

 ponds containing warm-water fish. It was attempted to make the ponds more 

 productive by fertilizing them and allowing them to remain dry several weeks 

 during the winter. The production of bass during the spring of 1928 was 

 rather disappointing. Approximately 17,500 fingerlings were collected, but 

 the muddy water rendered it impossible to determine how many more remained 

 in the ponds. Rock bass, crappie, and sunfish also were handled, but it is 

 evident that the production will be limited. Sixty adult channel catfish were 

 transferred to the station in the hope that they would propagate. The majority 

 were lost during the winter, and it was necessary to plant the rest in local 

 waters. 



Bourbon (Mo.) substation. — This cooperatively opei'ated substation produced 

 rainbow-trout eggs of good quality, the season's collection being the largest 



