486 U. S. BUREAU OF FISHERIES 



used, the water supply being taken from the city waterworks. The 

 depth was from 2 to 3 feet, and throughout the whole extent there 

 was a dense growth of water plants, among which crustacean food 

 naultiplied, new siipphes being brought in from the water pipes. 

 Fingerling shad are so tender that the numbers annually liberated 

 could not be ascertained. They can not stand the handling consequent 

 upon counting, not even undergoing transfer in dippers of water, and 

 their scales drop off on being touched. Consequently, at high tide 

 they were liberated into the Potomac through a sluice gate with an 

 outlet pipe about 2 feet in diameter. They required some days to 

 make their escape. By conservative estimate 50 to 60 per cent were 

 safely held until about October. Owing to the difficulty in obtain- 

 ing suitable rearing ponds, and the necessity of providing the ponds 

 with a water supply that will produce sufficient natural food, the 

 Bureau of Fisheries prefers to liberate the young shad, soon after 

 hatching, on their natural spawning grounds. 



TRANSPORTATION 



Good, healthy fry will pass from the jar to the collector tank as 

 fast as hatched ; they sometimes crowd on the side nearest the strong- 

 est rays of light. As many as 500,000 to 800,000 are collected in 

 each tank. In transporting they must be kept in vessels with a 

 smooth surface, about 2,000 to 3,000 fry to a gallon of water. The 

 water in the cans must be well aerated and kept at 58° to 65°, 

 though in rivers and ponds the fry endure a temperature of 80° F. 



For a number of years the bureau followed the policy of making 

 plants of shad fiy regularly in most of the important shad streams of 

 the Atlantic seaboard, but the results did not justify a continuance 

 of such efforts, partly, at least, because of conditions mentioned 

 herein. Finally, in order to maintain the diminishing numbers at 

 points where artificial propagation is conducted, it has been found 

 advisable to discontinue all shipments of shad eggs or fry to outside 

 points and to return the entire product of the hatcheries to local 

 spawning grounds. 



The inadequacy of supply in waters where shad are now propa- 

 gated makes it impracticable to distribute eggs or fry to other areas. 

 It is important that the fishery be rehabilitated, and to do so more 

 adequate conservation measures must be provided by the individual 

 States. 



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