XVI REPORT OF THE COMMISSIONER OF FISHERIES 



a vast economic saving is accomplished. At fishing centers too re- 

 mote from hatching facilities to permit of incubating the eggs it 

 has been the bureau's policy to fertilize and innnediately return 

 them to the local spawning grounds. This has been the method 

 of procedure in the Georges Bank cod and haddock fisheries ott" the 

 New England coast, where inmiense numbers of eggs are available 

 during the spawning season. 



In no case does the large output of practically every species propa- 

 gated exceed the requirements, and in most instances it is inade- 

 quate. This is especially true of such pondfishes as the black basses 

 and the crappies. It is the policy of the bureau to use a large per- 

 centage of the output of certain interior hatcheries for stocking the 

 lakes and streams in publicly owned lands. In arranging for such 

 plants the fish are delivered at the shipping point nearest the waters 

 and are transported thereto and liberated through the cooperation 

 of forest rangers and other Government representatives. 



The salvage of food fishes stranded on overflowed lands along the 

 Mississippi River continues to be one of the most important branches 

 of the bureau's fish-cultural Avork, These fish usually spawn when 

 the river is at flood stage, and the high waters allow the adult fish 

 to seek sheltered nesting places on the overflowed lands. With the 

 recession of the waters the adults return to the river, but the young 

 fish resulting from their eggs are imprisoned in temporary waters 

 where, if allowed to remain, they would be killed by drought or the 

 freezing of the pools later in the year. 



Another important activity is the inoculatioi) of these salvaged 

 fishes with the glochiclia of fresh-water mussels. This work has 

 proved to be of material assistance in maintaining the supply of 

 fresh-water mussels, which furnish the raw material used in the 

 highly important pearl-button industry. In 1922 the take of mussel 

 shells' approximated 26,000 tons, valued at more than $1,000,000 

 to the fishermen. During the past season the number of glochidia 

 attached to the gills of living fishes prior to their liberation is esti- 

 mated to have reached a total of 1,335,000,000. 



KELATIOXS WITH STATES AND FOPvEIGN GOVERNMENTS 



There is a growing appreciation of the need for increased fish- 

 cultural operations in the several States. This is evidenced by an 

 expansion of State operations and an enlargement of their coopera- 

 tive relations with the bureau. 



In past years much duplication of effort occurred in the work of 

 distributing fish. Cooperation with State officials has now been 

 brought to the point where it effects a material saving of funds 

 and efficiency of operation. Each year frequent exchanges of sur- 

 plus eggs are made between Federal and State hatcheries, ancl profit- 

 able results are being attained in the conduct of cooperative egg 

 collections under the direction of representatives of the bureau or 

 under the supervision of State officers. During the past year the 

 services of several of the bureau's employees were loaned to assist 

 State authorities in fish-cultural work, including the location and 

 construction of hatcheries, or to give expert fish-cultural advice. 

 The authorities of the States bordering the upper Mississippi River 

 have rendered valuable assistance in transferring fish from tem- 



