UNITED STATES FISH COMMISSION. UNITED STATES, FISH-CULTURE IN. 801 



United States. In the Potomac alone the an- 

 nual yield has been increased from 668,000 

 pounds in 1877 to an average of more than 

 1,600,000 pounds in recent years. 



The carp-ponds for the rearing of German 

 carp, in Washington, have been furnishing 

 these ti.sh to the people since 1879. Into every 

 State and Territory of the Union the carp have 

 gone to increase the stock of domesticated 

 fishes, and in suitable waters their growth has 

 been remarkable. A scale-carp sent to Texas 

 when four inches long increased to twenty and 

 one half inches in eleven months, and gained 

 about four and one half pounds. Large carp 

 not infrequently are sold in the market of 

 Washington, which have sprung from escaped 

 fishes in the Potomac, and they are readily 

 sold notwithstanding the high price (twenty- 

 five cents a pound). It is estimated that fully 

 30,000 ponds have been supplied with carp. 

 In 1882 alone, carp were distributed from the 

 Fish Commission ponds in Washington, in lots 

 of twenty, to 10,000 applicants, representing 

 every State and Territory of tbe Union, at an 

 average distance of more than 900 miles ; the 

 total mileage of the shipments baing about 

 9,000,000, and the actual distance traversed by 

 the transportation-cars, 34,000 miles. 



UNITED STATES, FISH-CULTURE III THE. Mod- 

 ern fish-culture involves the artificial taking 

 and impregnation of eggs ; providing for them 

 shelter and a suitable supply of water during 

 the period of incubation; the protection and 

 feeding of the young; the transportation of 

 the fry and eggs; facilitating the ascent of 

 fish in streams to their natural spawning-beds 

 by removing obstructions and impurities in 

 the waters; legislating against over-fishing, 

 injurious fishing, and otherwise destroying in- 

 dustries; the artificial rearing of inferior spe- 

 cies as food for such as have commercial val- 

 ue ; the introduction into new waters of species 

 which are known to be important elsewhere; 

 and the systematic study of all the natural con- 



ditions which affect the movements and some- 

 times the existence of aquatic animals. 



The mere hatching and depositing of fish- 

 eggs artificially is but a small portion of the 

 art of fish-culture as now practiced. It is 

 quite as important to remove obstructions and 

 impurities from streams, to prevent improper 

 fishing, and to study the capabilities of waters 

 for supporting life as it is to stock them with 

 an abundance of fry. The word u fish-culture " 

 no longer serves to convey the meaning in- 

 tended ; the term " aquiculture " is more near- 

 ly adequate to the purpose, for we have to deal 

 with all the objects of fishery whales, seals, 

 crustaceans, oysters, corals, sponges, and every 

 form of aquatic life. Fish-culture is simply 

 one of a series of means to an end. Wherever 

 unfavorable conditions exist, it must be com- 

 bined with systematic investigation of the nat- 

 ural causes affecting the movements of aquatic 

 animals, and with such intervention against 

 obstacles of all sorts as will insure the full 

 benefits of artificial introduction of economic 

 species. 



All civilized countries now make provision 

 for the artificial rearing of fish. The necessity 

 for this is more particularly felt in the rivers, 

 where the direct consequences of man's mis- 

 takes are more apparent than in the open sea. 

 If the salmon and the shad, which periodically 

 ascend our streams for the purpose of repro- 

 duction, met with no serious obstructions upon 

 their way, perhaps the necessity of fish-culture 

 would not be so clearly seen. In July, 1879, 

 at Bainbridge, Lancaster co., Pa., I saw great 

 shoals of shad-fry, the individuals of which 

 averaged more than two and a half inches in 

 length, lining the east shore of the river. At 

 the same time the Pennsylvania Canal, which 

 there follows the course of the river, contained 

 similar s\varms of the young fishes. At vari- 

 ous times during different years this phenome- 

 non has occurred, yet at no time since those 

 observations has there been a good catch of 



VOL. xxin. 51 A 



