[69] POND CULTURE. 535 



to reach a somewhat favorable result, in spite of the very anomalous 

 local conditions. If there were no large losses, it would be sufficient to 

 raise in the raising iwnds only that number of fish which remain for 

 the market. In that case, the ratio of stocking would be about as fol- 

 lows : For the raising ponds of the first class, 768 fish per hectare; sec- 

 ond class, 446 ; for the stock ponds, 130. 



Even these figures must be considered rather high, especially as re- 

 gards the raising ponds, and show the excellent quality of the Peitz 

 j)ouds, in which young fry are, in a i^eriod of four years, developed to 

 marketable fish. 



V"on dem Borne* who does not make the distinction of raising ponds 

 of the first and second class, gives the following figures as the proper 

 ratio per hectare: For si)awning ponds, 9.6 spawners, 6.4 niilters, 3.2 

 drivers ; and for raising ponds, good, 600 to 800 fish ; medium, 400 to 

 600; poor, 100 to 400. 



G. Kraft t gives the following figures: Spawning ponds per hectare, 

 6 to 12 spawners, 4 to 8 milters, and to every 3 milters 1 driver; raising 

 ponds of the first class, 300 to 600 fish, average 450 ; raising ponds of 

 the second class, 180 to 420 fish, average 300 ; stock i)Ouds, 120 to 180 

 tisli, average 150. 



As they are, these figures cannot serve as a general guide if we take 

 the relative size of the various kinds of ponds as given above, because 

 they do not meet the first demand of a well-regulated pond farm, viz., 

 that the number of fish needed for the stock ponds shall be raised in 

 the raising ponds. If we calculate the ratio of stocking on the basis 

 of the relative size of the different classes of ponds, as given above, 

 which on the whole seems to be correct, we obtain the following result : 



Ponds. 



Number of flsh. 



Area. 



Min- . . „ Max- 



I Hectares. \ ■ I 



Raising ponds of the first class 12 3,600' 5,400 7,200 



Eaising ponds of the aCcond class i 18 3, 240 i 5,400 7,560 



Slock ponds (one year's course) ; 60 7, 200 i 9,000 10,800 



Stock ponds (two years' course) i 30 ;i, 600 I 4, 500 5, 400 



Stock ponds (three years' course) 30 3, 600 4, 500 5, 40o 



It will be seen at a glance that in a one year's course the raising ponds 

 cannot produce the necessary number of fish for the stock ponds, and that 

 if the two years' course is adopted, more fish are produced in the raising 



* Von dem Borne, Fischzucht. 

 tG. Kraft, Landwirthachaft. 



