MANUAL OF FISH-CULTURE. 93 



The Michigan streams exemplify the practical results attained in 

 the introduction of brook trout in new waters. The Au Sable Eiver 

 was long thonght to be especially adapted for this species, but it 

 abounded with grayling, and until this beautiful fish began to disappear 

 no movement was made toward introducing the brook trout. The 

 lumber interests of that section made it necessary to use the river for 

 conveying logs to various points downstream, and, as the log-driving 

 could be done only during the spring freshets, it came just at the time 

 when the grayling were on their spawning-beds. They were driven 

 away and the beds destroyed by the plowing of logs through the 

 river bottom each year, till the fish gradually began to disappear. 

 The brook trout was suggested as the proi^er substitute, because its 

 spawning season is in the autumn when the river is undisturbed, and 

 the Michigan Fish Commission began the work by planting 20,000 fry 

 in the year 1885. Though additional jilauts were made from time to 

 time, both by the Michigan aud United States Commissions, no results 

 were observed for some years, and it was thought that the work had 

 been a failure. But the natural instinct of the fish had caused them 

 to push from the main river into the small tributaries, where they 

 multiplied and grew during these years till they finally crowded down 

 into the river itself. Here they found as suitable a home as in the 

 small streams, and their numbers gradually increased till now the 

 stream is completely stocked. 



In the autumn of 1805 a camp was established for the United States 

 Fish Commission 9 miles below the village of Grayling for the purpose 

 of taking spawn from wild fish. The work was confined to rod-and-line 

 fishing until the spawning season opened, when it was found necessary 

 to adopt some other plan, as at this time the trout refuse to feed. 

 During the five weeks, in which the rod was used exclusively, 3,000 

 spawning fish were taken. A small seine was then used for capturing 

 the fish, by hauling it at right angles to the current of the river, directly 

 across the spawning-beds, which thickly dotted the river bottom in 

 some places. By this method a tubful of trout at one haul was often 

 taken, and during the period the fish were running between 8,000 

 and 10,000 were obtained. This illustrates the abundance in which 

 this species is found in a river to which it has been transplanted. A 

 conservative estimate would place the number of trout taken from 

 this stream in the season of 1895 at 100,000, perhaps 25 per cent being 

 rainbow trout. Other waters of the State have been successfully 

 stocked, so that the northern half of lower Michigan now contains a 

 network of trout streams, made by introducing this fish into waters 

 where it was not indigenous. 



In its native haunts, whether in lake or stream, the brook trout is 

 usually found in the same clear, cold, spring water, and prefers brooks 

 or streams flowing swiftly over gravelly bottoms. It pushes from the 

 rivers into the small streams, seeking the headwaters, searching out 



