in the same manner as in the growing pond of the large scale operation of carp culture, 

 and in addition can be stocked with not too small tenches. The tenches must naturally 

 be so heavy that they likewise will have grown to table fishes in the autiwin. 



The setting in of rainbow trout is only exceptional and is advantageous only in 

 deep, cool, hard soil ponds, since trout are too sensitive in every respect for the 

 small management. An intensive feeding of the trout is too troublesome and can be profit- 

 able only in medium and large managements, 



A special position is taken by many permanently water covered naturally damned ponds 

 of the intermediate mountains. In the Upper Harz Uountains, these "ponds" are centuries 

 old, about 6 to lA meters (19 to ^6 ft.) deep at the plug, mostly hard bottomed, and were 

 formerly used for water supply purposes. The area of the smallest of them amounts to 

 about 6 hectares (l/,.8 acres), the water is extremely deficient in lime. The hard bottom 

 ponds are stocked with rainbow or brook trout vitellin-sac brood A, 000 per hectare (1620 

 per acre) of which about 600 one-year rainbov.- or brook trout are again caught in the 

 autujnn. The muddy ponds receive in part a stock of about 80 one-year carps per^hectare 

 (32 per acre) of which about 60 two-year carps of 350 grans (12.3 ounces) are harvested 

 in t he autumn. For the other part the muddy ponds are stocked with two-year carps. The 

 growth increase per hectare (water surface and pond area vary frequently) vrLth two-year 

 carps aTiounts to about 20 kilograms (17.8 pounds per acre), in stocking with two-year 

 rainbow or brook trout about 10 kilograms (9pounds per acre). The losses are normal, 

 at the same tir.e the piece grov^th-increase of the two-year carps is moderate. To be 

 sure, these ponds of the Upper Karz today can hardly be called small pond managements, 

 because the ponds are very numerous and are operated in conjunction. At my suggestion, 

 they are novi used preponderantly for the production of spawn trout and trout finger- 

 lings which are later fed up in small normal ponds to table-fish size. 



;ion-drainable ponds can be stocked with tr.out, especially rainbow trout, if they have 

 fonaerly deep gravel pits and cool water. The trout are relatively easy to hook and to 

 catch with weir baskets and nets. Carps must not be placed in non-drainable ponds unless 

 these can be very well fished out with drag nets, or when as sometimes happens they can 

 be pumped out cheaply. Under such conditions the carps even produce very good yj.elds and 

 are to be preferred above all other kinds of fishes, as was shown to me among other things 

 by the operation of the extremely numerous turf pits in Warthebruch with two and three- 

 year carps. AL-nost every small proprietor there, has his turf pit in which he successful- 

 ly produces carp flesh. 



The stock fishes are mutvially purchased through an association organized for this 

 purpose by numerous pond owners. This is a procedure which also deserves to be recommend- 

 ed to the small pond owners of other localities. In non-drainable ponds especially, 

 operations must, of course, be conducted as cheaply as possible. Large expenses for 

 catchinr equipment and transportation must not be incurred. Unfortunately good fishing 

 out cannot be done with the drag net in many small ponds. The village ponds are especial- 

 ly known as gathering places for trash of all kinds, v/hich retards the fishing. VTarm, 

 poorly fishable, non-drainable ponds consequently had best be operated with tenches, also 

 crayfish or eels or if there are moor ponds also with crucian carps and pikes, vfhich can 

 be readily trapped in standing appliances. This kind of operation already borders on 

 lake operation. Its treatment, strictly speaking, no longer belongs in the problems of 

 this book, which deals v^lth "pond" operation. I shall only point out, that with operation 

 in such cases the ruling principle must be to thoroughly and continually fish out these 

 non-drairj.ble small -.vaters with weir baskets, regulating nets, pole nets, adjustable and 

 lajrino- hooks, llnrke table fishes should be utilized as soon as possible. Only then can 

 the ;n.eld be satisfactory. Unfortunately there are still many small waters which can be 

 used only incompletely or not at all. It would be a profitable policy for all fishery 

 societies to bring about an increased well planned operation of these waters by proper 

 information and instruction. 



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