1172 U. S. BtTREAU OF FISHERIES 



these eggs to the amount of 345,053 were planted in local waters prior to the 

 absorption of the sac, and the remainder were reared with the view of selecting 

 the best among them for use as a future brood stock. At the close of the 

 year the records showed 233,307 fingerling fish on hand, many of which were 

 approaching the No. 3 fingerling size. This is by far the best record that the 

 station has made. 



Work along the line of improving and developing the station was prosecuted 

 whenever fish-cultural operations would permit. Such development work con- 

 sisted largely in the extension of the canal and pond system. A diversion dam 

 and extensive flood spillway were constructed along the main West Branch and 

 the canal way for approximately 1,000 feet to tbe valley of Diversion Brook ; 

 and during the winter, after the supply of wood for fuel was cut, cement 

 material for the intake was hauled to the canal way and a considerable amount 

 of grading was accomplished. Improvements to station buildings were con- 

 tinued and extensive repairs were made on the station power plant, iron 

 buckets being installed in the water wheel and the dynamo practically rebuilt. 

 In the course of the year two large ponds were completed, partially flooded, 

 and put in commission for the retention of brood stock. 



PITTSFOBD (VT.) STATION 

 [Dr. H. S. Davis, Director; R. F. Lord, in charge] 



A considerable portion of the time was spent in providing facilities for 

 holding an increased stock of fingerling and adult trout. Six additional ponds 

 and another 12-compartment raceway unit for experimental work were com- 

 pleted. Two of the fingerling ponds are of the circular type, insuring an eflScient 

 water cii'culation and a uniform distribution of the fish thi'oughout the pond 

 area. Arrangements were also made to lease additional land, which will 

 permit of the construction of six small spring-water ponds for the wintering 

 of fingerling fish. The general experimental work in relation to trout foods, 

 selective breeding, etc., was very successful. One series of feeding experiments 

 was completed in September, 1929, and another started in the succeeding April. 



There being an insuflBcient surplus of brook-trout fingerlings to permit of 

 a distribution in the fall of 1929, the plantings were confined to the liberation 

 of larger fish. Among them were 450 tagged rainbow and steelhead trout 

 from 1 to 3 pounds in weight. These were deposited in Vermont waters and 

 reports on them have been coming in since the opening of the fishing season 

 on the first of May. The liberations also included 675 brook-trout yearlings 

 6 inches in length and one hundred and sixty 2-year old brook trout averaging 

 a pound or more in weight. The only fingerlings available for the fall dis- 

 tribution were two small lots of landlocked salmon and rainbow trout. The 

 spawning of the station brood stock of brook trout began October 29 and 

 additional eggs were taken to December 11, inclusive. For the first time 

 since the station was operated it was unnecessary to secure eggs of this 

 species from other sources. A sufficient number of eggs were taken to more than 

 serve experimental needs and shipments both of eyed eggs and advanced fry 

 or small fingerlings to a total of about 280,000 were transferred to other sta- 

 tions. In addition to the general spawning 55 pairs of selected brook trout 

 were stripped and eggs kept in individual lots. The best record made by this 

 stock was in the case of one lot that finished the fiscal year with a loss of 

 only 9 per cent from the green-egg stage. Only the best of these lots will be 

 retained for a future brood stock. 



About the middle of December approximately 15,000 eggs were secured from 

 a selected stock of rainbow trout reared from spawn produced at the White 

 Sulphur Springs (W. Va.) station. Black-spotted trout, hatched from Yellow- 

 stone Park eggs in 192G, were stripped for the first time on April 15 and 

 yielded eggs of exceptionally fine quality. Montana grayling, hatched in July, 

 1929, were successfully carried through the winter and by the close of the fiscal 

 year some of them had attained a length of 6 inches. Experimental lots 

 of rainbow trout and steelhead began spawning in April but their eggs were 

 decidedly inferior to those secured from the black-spotted trout. In coopera- 

 tion with the Vermont Department of Fish and Game, planting experiments 

 involving both the grayling and the black-spotted trout will be instituted in the 

 near future. 



