Henshall. — Planting of Fish 167 



These conclusions are sane, sound and sensible, and agree with 

 those of all practical fish culturists who have given the matter 

 earnest thought and consideration. 



As a general thing the streams of the eastern slope of Mon- 

 tana, Colorado and Nevada are comparatively pure and uncon- 

 taminated, except in the immediate vicinity of mining camps. 

 There was always an abundance of fishes native to the streams, 

 and their natural food was likewise abundant. Cut-throat trout, 

 Rocky Mountain whitefish, and in certain streams, grayling, lived 

 harmoniously, were well nourished and reproduced their kind 

 year after year, a natural balance of species being maintained. 



If these conditions had not been disturbed by the introduction 

 of alien species, and depleted waters had been stocked with native 

 fishes, this happy and natural condition of affairs might have 

 continued for many years to come. 



As a case in point I will instance a stream that was under my 

 daily observation for many years. Bridger Creek, a fine mountain 

 stream, flows within a hundred feet of the Bozeman hatchery. 

 When I began operations there in 1896 the Creek was well stocked 

 in about equal numbers with cut-throat trout, grayling and 

 Rocky Mountain whitefish, and this relative condition had always 

 existed. At the end of thirteen years, 1909, when I left the station 

 for Tupelo, Mississippi, the waters of Bridger Creek contained 

 neither grayling nor whitefish, and but very few cut-throat trout. 

 This change was brought about through the accidental stocking 

 of the creek with brook and rainbow trouts from the waste water 

 of the hatchery and ponds. These aggressive species were in 

 entire possession of the stream, the brook trout being in the 

 majority, though neither species was as abundant as the natives 

 were formerly. As the spawning season of the brook and rainbow 

 trouts are at different times, spring and fall, this balance will 

 probably be maintained through the depredations on the eggs, 

 fry and fingerlings of each other. 



At that time all the streams of eastern Montana were well 

 stocked with native fishes, mostly cut-throat trout and whitefish, 

 while the grayling existed with them in the tributaries of the 

 Missouri River above the Great Falls. Subsequently indiscrim- 

 inate stocking of these waters was made with alien species of 



