592 REPORT OF COMMISSIONER OP PISH AND FISHERIES. 



"To feed such a large number offish with insects is almost impossible, 

 as insects, such as water-palmers, flies, their larvae, &c, are very scarce 

 in that neighborhood, and frog-spawn and cheap fish cannot be had. 

 In Eettenbacher's opinion, every pisciculturist who cannot obtain insects 

 and whose space is limited, should only raise the Salmo salvelinus, since 

 this fish alone can in a small space be fed on meat from its infancy till 

 it is ripe for the market, and has the lowest percentage (7 per cent.) of 

 mortality. It is a very gregarious and tame fish, which does not seem 

 to be disturbed by being placed among fish of different species and size, 

 while the trout is always shy and of an unfriendly disposition, especially 

 toward small fish. 



" Eettenbacher sells his fish at the age of two and one-half to three and 

 one-half years, and only those whose growth has been retarded, at the 

 age of four and one-half and five and one-half years. Kecently, he has 

 commenced to hatch a larger number of fish than he requires, and, after 

 a year or more, he throws those whose growth has been retarded into the 

 open water, leaving them to shift for themselves, because, according to 

 his theory, the gain is much greater if the expensive food is given to 

 such fish as promise a better growth. His spawn he gets from the 

 Aussee Lakes in Styria, where, during the spawning season, he annually 

 buys several hundred female fish, impregnating their eggs with milt 

 from male fish of his own raising, as very few male specimens of the 

 Salmo salvelinus are found in those lakes, and as those few are mostly 

 worthless. The female fish he keeps till next summer, when he sells 

 them. In 1870, Eettenbacher did not hatch any fish, since he had such a 

 large number left over from the year before as to make it impossible 

 for him to supply all the necessary food. The water used in his estab- 

 lishment consists of several hundred small and large springs flowing 

 from the ground, with a temperature of 5£ degrees Eeauinur in winter, 

 6£ in summer ; near the Traun river 3 degrees in winter and 9 in summer. 

 In this water, the young fish leave the eggs after fifty or sixty days. 



" Up to 1864, Eettenbacher had only two small hatching-boxes. In 

 1864, he built a hatching-house with four boxes and two tanks for the 

 young fish; in 1865, he built a covered tank with three divisions; in 

 1866, he dug the two ponds; in 1867, he built a new hatching-house J 

 and in the same year, after having obtained the upper portion of the 

 Altwasser stream from the imperial forest office, in exchange for a 

 portion of forest belonging to him, he stopped the communication be- 

 tween his springs and the Traun Eiver by a stationary wooden gate of 

 lattice- work, and built his floating hut and boat, and, in 1868, the watch- 

 house, resting on pales. The total capital invested was $258.25. The 

 location was extremely favorable for making the ponds, as but very 

 little digging had to be done. According to the inventory taken, with 

 a view to his obtaining the government prize, on the 29th and 30th of 

 June, 1870, when all the fish were carefully counted and weighed, his 

 establishment contained the following number of fish : 



