ponds that are at all times vrell peopled with mollusks are therefore especially well 

 adapted for the rearing of tench. 



It is an erroneous belief that tench require entirely different natural food than carp 

 or even feed upon the excrenents of carp. This should be kept in mind wherever the mixed 

 breeding of carp and of tench is attempted. 



Trout. TThile trout are endowed v.lth the dentition of predatory fish, they are never- 

 theless j and almost exclusively "Insectivores", during the first three or four years of 

 their lives. Their predatory character, though is apparent, since they feed mostly upon 

 larger insects. They will even swallow foreif^n matter, such as the usually wood and stone 

 covered "quiver" of trichoptera. Even jilittering, metallic objects may be found in their 

 stomachs. 



It is presumed that the lon^ period of insectivorous food habits was developed in 

 trout. As a rule, trout do not find sufficient numbers of companion fish — in brooks — 

 upon which they may feed, such as minnow, for instance. 



Also, trout fight shy of their otti kind. The brown trout is an outspoken hermit and 

 simply loves to hide out. 



It is characteristic for trout that they v.411 remain insectivores the longer, the 

 more plentiful by such food can be had. 



In small breeding tanks and in overcrowded ponds, the rapacity of trout asserts itself 

 already in their own, small fry, as soon as they are able to feed. They will prey upon 

 weaklings of their own kind and the si.ialler fish form a much appreciated diet for the larger 

 ones. The brov/n trout surpasses the rainbow trout in this respect. 



The gluttony of trout reveals itself already in the smallest fiy. Even in their period 

 of still partial vitelline sac feeding, they will already sv/allov; Gladocerae, Copepodae, 

 Chironomidae and Chaetopedae, (Schroder), 



The main food of 50 daj's old trout, in larger ponds, consists of Chironomidae, especial- 

 ly the larva of such species as Ceratopogen, Tanypus, Tanytarsus, Orthocladius, but also of 

 Chirononms. (Schaeperclaus 1928) 



In less plentifully provided ponds, other larva, shore Cladocerae and Cyclopidae will 

 be added to their diet by these young fish. 



In the' following table, arran,';ed by P. Schiemenz (following Schgeperclaus), the different 

 items of natural food, favored by trout are listed in the order of their importance. 



In Brooks In Ponds 



Amphipodae Larva of chironcMnida 



larva of trichoptera Larva of trichoptera 



Larva of chironociida Larva of chrysopa 



Larva of ephemera Corixae 



Haliotis "Air foodstuffs" 



"Air foodstuffs" Sidae, Daphnae 



Alonse 



Cypxidae 



Amphipodae nay be spoken of as THE trout diet, so much so in fact, that the abundance 



of trout in brooks quite often depends upon a plentiful supply of Aiiphipodae . 



Rainbow trout and " La chs siblings" (Salmon salvelinus) requii-e the sane kind of food- 

 stuffs. Only in mountain streajns do rainbow trout, more than brook trout, feed moi-e on 

 diptera larvae and mollusks, although investigations made by Stankovd.tch at different times 

 of the year (1924-) have hardly shown any marked differences. 



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