XXX.-HOW CAN OUR LAKES AND RIVERS BE AGAIN STOCKED 

 WITH FISH IN THE SHORTEST POSSIBLE TIME?* 



By Mr. von dem Borne, 

 Landed Proprietor at Berneuchen, near Wusterwltz. Neumark, t'russia. 



The decline of our fisheries is only in part to be ascribed to the prog- 

 ress of civilization ; for, to a great extent, it has been caused by the 

 senseless manner in which the fisheries have been carried on. If, there- 

 fore, the fisheries are carried on in a rational manner, it would certainly 

 be easy to stock our waters completely, especially if we take into con- 

 sideration the extraordinary fruitfulness and the rapid growth of fish. 

 Mr. Horak, the superintendent of the immense ponds at Wittingau in Bo- 

 hemia (covering an area of about 15,043 acres), told me he was confi- 

 dent that he could in a few years stock the Elbe to its utmost capacity 

 with fish, if a stop were put to the plundering of the river ; and I am 

 thoroughly convinced that Mr. Horak is right. 



The first question to be settled would be what kinds of fish would 

 be best suited for making our waters productive. We have migratory 

 fish, like the salmon and the May-fish, which live in the sea, but spawn 

 and spend their first youth in the rivers ; for the brooks with gravelly 

 bottom, we have the trout and the grayling; and for the deep lakes, 

 the saibliug, the different varieties of the muraena, the raaken, &c, are 

 of importance. For shallow lakes, and for rivers and brooks which 

 have no gravelly bottom and flow slowly, the carp is undoubtedly the 

 most suitable fish. We will now devote our attention to the last-men- 

 tioned kinds of waters. 



Our lakes and rivers contain fish which require very different food, 

 and we accordingly divide the fish into fish of prey and peaceful fish, or 

 mto fish living on fish, those living on insects, and those living on plants. 

 The pike chiefly lives on fish, the perch lives on fish and insects, and the 

 carp on plants and insects. In the household of nature, the occurrence 

 of fish of prey aud peaceful fish side by side is of the utmost importance. 

 Those fish which live on plants are important, because they find most of 

 their food in the water, and consequently produce the greatest quantity 

 of flesh in a given sheet of water. But if their number exceeds a certain 

 limit, so that the quantity of food does no longer suffice to supply the 

 demand, the fish not only decrease in size but also in number, so that 

 the total weight of fish produced by that sheet of water declines steadily 

 from year to year. This is remedied by the fish of prey, especially the 

 pike, not only because they eat the small fish, but also because they 



"From Circular No. 1, 1876, of the Deutsche Fisherei-Verein. 



6S1 



