538 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [72] 



by itself. Ev^en in small or iiieclium-sized poutl farms wbicli possess a 

 great number of pouds this method will be found profitable. As the 

 increase in the weight of the fish per annum in the stock pond will in- 

 dicate the number offish with which it is to be stocked, if this increase 

 is to reach a certain height within a given period of time, and as the 

 relative proportion of the i)onds should be such as to enable them to 

 produce the number of fish required for the stock pouds, we should be 

 able, on the basis of the relative size of the ponds as given by us, to fix 

 the proper luimber of fish for the raising ponds of the first and second 

 classes. To do this it will be necessary only to regulate this number on 

 the following principle : Stock pond = 1 ; raising i)ond of the first class 

 = 2.5; raising pond of the second class = l.GG (or 1.G7) ])er hectare. 

 The relative size of the ponds, as given by us, will, however, oidy be 

 advantageous if it is intended to work the stock pouds in a two years' 

 course. The number of fish which we gave for a one year's course in 

 the stock ponds is rather low ; and if we wish to api)ly this number to 

 a two years' course — wliich may be done in good ponds — ami thus luake 

 the fish marketable in the fourth year, the proportion of the dilleient 

 classes of ponds will have to be changed, and would in a total pond 

 area of 100 hectares be as follows: 



Ilectiirea. 



Spawning ponds 6 



Raising ponds of tlio first class 17 



Raising pouds of the second class 25. 1 



Stock ponds 42. 5 



Winter ponds 9 



Total 100 



Supposing the stock pond could stand onlj'^ 100 fish per hectare, we 

 get the following number of fish per hectare: Kaising ])onds of the first 

 class, 100x2.5=2o0 fish; of the second class, 100 x 1.00= 100 or 1(»7 fish; 

 and the entire immber of fish would be distributed as follows : 17 hec- 

 tares raising ponds of the first class at 2o0=4,2o0 fish ; 25.5 hectares 

 raising ponds of the second class at 100 to 107=4,233 to 4,250 fish; 42.5 

 hectares stock jionds at 100=4,250 fish. The difference between the rais- 

 ing pond of the second class and the stock pond (17 fish) is caused by 

 the repeating decimal fraction (1.0 -f), and is very insignificant, and 

 we place in the raising pond of the se(;ond class 4,250 fish, because if 

 we were to stock the raising pond of the first class in exact proi)ortiou 

 to the stock pond, we would at any rate have these 17 fish on hand. If 

 we liad regulated the stocking of the raising pond of the first class ac- 

 cording to that of tiie stock i)ond, that of the raising pond of the second 

 class will regulate itself naturally, according to the stocking of that of 

 fhe first class, and small differences need not at all be taken into consid- 

 eration. All that can be done in laying out the jdau for managing a 

 pond farm, will be to get approximate figures, so as to have some sort 

 of a basis of operations and not to work entirely in the dark until expe- 



