524 REPORT OF COMMISSIONER OF FISH AKB FISHERIES. [58] 



should be chased away or caught, and neither <lucks nor geese should 

 be allowed on the i)()nd. The frogs should, if possible, all be removed, 

 and in selecting a spawning pond, ponds containing many frogs should 

 be avoided. If the ponds have but few or no aquatic i^lauts, and are uot 

 surrounded by bushes or shaded by trees, few injurious animals will 

 be found in or near them ; and even if there should be some, they can 

 easily be discovered and rendered haru)less. 



Spawning ponds need not contain a very large quantity of fish-food, 

 for the quantity required by the young fry and the parent tish will not 

 be great. On the contrary, ponds (containing a scanty supply of Ibod 

 are to be preferred for spawning ponds, because a superabundance of 

 food hinders the propagating i)rocess. Young lisli which hav^e been 

 raised in i)onds containing a great deal of food are, as a general rule, 

 retarded in their growth when placed in poor raising i^onds, while, on 

 the other hand, fish which have lived on short rations will grow rapidly 

 when placed in good raising ponds. If it is thought that a i)ond con- 

 tains too nuich fish-food it will be well to place in it some more spawn- 

 ing carp, for a superabundance of young fry will never do any harm. 

 Teichmaun says on this subject: "The soil does not influence the pro- 

 duction of fish as much as many people seem to believe. It is certain, 

 however, that rich soil is rather injurious tlian otherwise, for in the 

 spawning ponds the fish are to be produced, and not to be fattened." * 

 Tbu'ak says: "The bottom of sjuiwuing ponds should not be compose«l 

 of peat or sand, nor should it be rich enough to produce grain, because 

 in the first case the young fish would be retarded in their growth by 

 want of food, while in the second case they would be spoiled in their 

 early age by too rich a food, and when transferred to the raising i)onds 

 would grow but slowly. The l)ottom of a spawning i)ond should, there- 

 fore, not be principally composed of humus, but be a medium, mihl, 

 clayey soil."t 



My views on this subject coincide with those expressed in the last 

 sentence quoted from Ilorak, and are that, as the nature of the car[) 

 rcMpiires good soil (among which 1 class medium clayey soil), the young 

 fry should liave the same kind of soil. But, apart from this, it cannot 

 be said when a spawning pond is selected whether it will otter ranch 

 or little food for the young fish, as the number of young ones produced 

 by one spawner varies greatly. As a general rule, 1,000 to 1,500 may 

 be counted to one spawner. Sometimes, however, there are less, and 

 often twice as many. For a smaller number the jiond may possibly 

 offer sufficient food, while a larger number would suffer want. It is a 

 common experience that young fish which, in poor or overstocked rais- 

 ing ponds, have been retarded in their growth, when placed during the 

 following year in better ponds will make up for lost time. Thus I can 

 state from my own experience that in an overstocked pond the young of 



* Teickmanu, Der erfahrene Fischmehisier, 1821. 

 tHorak, Teiclncirlhschiil'f, 18ti'J. 



