REPORT OP THE COMMISSIONER OF FISHERIES XXIII 



it is not practicable to send the eggs to the hatchery. This applies 

 to the buffalo fish work in Louisiana and at points on the upper 

 Mississippi River. The marine hatcheries are so situated that they 

 can be operated at minimum cost, and the output, therefore, is ob- 

 tained at a very low cost per million when compared with the collec- 

 tion of eggs of the salmon, whitefish, and other important commercial 

 species. At the Woods Hole station the codfish are purchased alive 

 from commercial fishermen and taken to the hatchery, where they 

 are placed in a large pool and permitted to spawn naturally. The 

 eggs being bouyant, they are collected in screen boxes as they pass 

 out of the pool to the water supply. After spawning the adult cod 

 are released in the ocean. 



MIGRATORY FISHES OF THE ATLANTIC COAST 



The most important species in this group is the shad, which is 

 having a hard struggle to maintain itself in northern rivers. The 

 catch of shad has been falling off at an alarming rate for a number 

 of years. At the present time the bureau is operating but one shad 

 hatchery, located at Bryans Point, Md., on the Potomac River. The 

 work on Albemarle Sound can not be considered, as shad propaga- 

 tion is conducted only at times when certain seine fisheries are in 

 progress. To a large extent weather conditions interfere with the 

 runs of shad or the number of eggs obtained at a given hatchery. 

 The dumping of trade wastes and the pollution of streams apparently 

 further the decline of the shad fisheries. Ten or fifteen years ago 

 shad were caught in the vicinity of Washington, D. C. ; now very few, 

 if any, shad are caught north of Mount Vernon. It appears that it 

 will be necessary for the States interested in the maintenance of shad 

 to take drastic measures in regard to their protection. There should 

 be a yearly and weekly closed season with a limitation on net fish- 

 ing in specified waters. Certain areas should be set aside by the 

 States as natural spawning grounds for shad and fishing in those 

 areas prohibited. Were such methods adopted, it is believed that the 

 shad would maintain themselves through natural reproduction. 



During the past season considerable attention was given to the re- 

 establishment of a temporary hatchery on the Roanoke River at 

 Weldon for the collection of eggs of the striped bass. If suitable 

 facilities can be obtained, it is very probable that this work will be 

 resumed. 



SALVAGING OF FOOD FISHES FROM OVERFLOWED LANDS 



During June, 1925, the upper Mississippi River was very low, 

 which prevented the adult fish from reaching spawning grounds 

 in the marginal lakes, with the result that the number of fish res- 

 cued, while greater than during the previous year, was somewhat 

 below normal. If normal rains do not occur in July and August, 

 the water level of the river frequently drops so rapidly that many 

 of the lakes dry before the bureau's crew can reach them. On the 

 other hand, heavy rains during the summer months cause the lakes 

 to maintain their level, when dense growths of aquatic plants 

 make it almost impossible to haul seines. No attempt was made to 



