Three year old tench should not possibly be again used as stock tenches, because 

 there is the danger that they will spawn, even if they are small, I have been able to 

 determine that even three year old female tench of hardly 9 cm. length (15 g) were fUlly 

 spawn mature. In comparison, the largest three year tench of about 4-00 g weight are 

 used again each year for the production of progeny as a means of producing a good race 

 of tench. 



If for any reason, three year old tench must again be set out, they are to be planted 

 with the sexes separated. The sorting (Fig. 21) can be accomplished in the shortest time 

 on the sorting table. 



All observers agree that female tench grow better than the males, in average by 

 about 30 percent (Nordquist quotes 35 to ^0 percent). 



Although the tench goes after food very well and very much better than the carp and 

 the yearling tench eats in cooler weather, a paying "tench masting" cannot be conducted 

 in small ponds according to existing experiments by Walter. 



It must also be repeatedly emphasized that the tench, by their moodiness and skin 

 sensitiveness, by the difficult hibernation of the yearlings, by the greater piece-count 

 per hectar, by the greater risk from fish foes and the difficulty of fishing out, often 

 give the pond operator special worry and work. The pond industries today have an import- 

 ant task in providing the lake and river fisheries with tench stock chiefly because in 

 the pond industries the tench can be kept completely free of Ergasilus disease. In non- 

 drainable or strongly weedy ponds the tench takes precedence over the carp. 



The Gold Aland (Lenciscus orfus)* 



This fish is used for "display" in aquariums, in garden ponds and in park lakes. 

 Some carp fisheries raise this fish for such purposes. It is a variety of the aland 

 (Idus melanotus Hedc). The gold coloring is due to an almost complete lack of black 

 color cells in the skin. Such "mutations" also occur in carp, tench, crucian, etc. I 

 have bred a pure race of gold colored tench by crossing two such colored fish. They are 

 practically unsuited for the table on account of the faded color of their meat after 

 cooking. 



The gold aland is preferred to other gold mutations for "display" purposes since it 

 is a more visible surface fish. Their culture requires hard-bottom ponds, and, as in the 

 case of tench, the breeder puts a few parent fish in the rearing ponds. Not too many, 

 though, in order to avoid a too large progeny of small fish. It is also advisable to use 

 only one pond for their spawning, which occurs in May, in order to facilitate stock 

 regulation. The older age classes, like with tench, may be kept Trith carps. 



The Crucian (Carassius vulgaris Nils). 



Fishbreeders, during the last few decades have paid little attention to this fish. 

 But since crucian of about 500 grams weight (about 1 lb.) bring rather good prices, it 

 seems that their culture would be quite profitable, although it offers the same diffi- 

 culties as the culture of tench. By guarding against over-propagation and introducing 

 rational methods of selection it would be possible to soon develop a race of fast 

 growing, that is, profitable fish. 



The crucian is easily distinguished from the carp by a black tail spot and the 

 lack of barbs upon the jaw. It is very resistant, demands even less oxj'gen then the 

 tench and is free from the oversensitiveness of the skin which is so annoying in tench. 



The fish spawns in May and June and glues its eggs to water-plants. The gold variety 

 is not to be confused with the real goldfish ( Carassius auratus ). a native of China. 



91 



