470 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. [4] 



INTRODUCTION. 



There are four different methods of cultivatiug fish : 



1. Pond culture. — a. Fish-culture, i. e., cultivating fish in spawn- 

 ing ponds (in which the fish spawn and in which the eggs are hatched), 

 raising ])onds (in which the fish remain till they have reached a con- 

 siderable size), and stock ponds (in which the fish are fattened for the 

 market), or in inclosed portions of streams. Fish-culture, therefore, 

 means the natural ])roduction of fry and raising the fish for the market. 

 h. The Iceeping of fish in raising ponds, stock ponds, or in inclosed por- 

 tions of streams ; in other words, raising young fish whiyh have been 

 obtained from abroad, and keeping them till they are ready for the 

 market. 



2. TuANSPLANTiNa FISH from one water to another, i. e,, transfer 

 ring a number of sexually mature fish to water in which prior to this no 

 such fish were found. 



3. The Chinese method, which consists in gathering from the water 

 the spawn of fish deposited in a natural laanner, and transferring it to 

 other places to bo hatched. 



4. AliTIFIClAL FISII-CULTUKE IN A NAEKOWER SENSE, /. <?., extract- 

 ing from the fish by human agency their sexual products, imiting the 

 male and female products, and protecting the eggs and young fish 

 from their natural enemies until the umbilical sacs are absorbed. 



In the following pages we shall treat only of the first-mentioned 

 method, although we shall at times in the proper connection allow our- 

 selves some digressions relative to the methods. 



Pond culture can be carried on only in sheets of water in which one 

 can arrange the water at all times according to his discretion. Such 

 waters are principally ponds, though they are sometimes lakes and in- 

 closed portions of streams. 



The larger and smaller lakes, which are termed inland waters, are 

 formed either by the gathering of water in low ground along the course 

 of rivers and brooks, in other words by streams overflowing their banks, 

 in which case these rivers or brooks flow through the lakes formed by 

 them without undergoing any change, or divide into several branches, 

 or occasionally find a subterranean outflow, or such lakes are the natural 

 receptacle for the water of an entire neighborhood, and are formed by 

 springs or by the waters flowing down from the mountains; or they owe 

 their existence to invisible subterranean streams. 



Large lakes must come under the head of the " wild fisheries," as their 

 water cannot be let off or diminished; and the principal condition for 

 successfully carrying on these fisheries is "to know how to catch fish." 

 Man can make his influence felt only by increasing the number of fisb. 



