Fish Culture in Inland Waters 297 



many small streams is very- likely to result in failure because the 

 stock generally put out in the East is of the migratory variety. 

 These rainbows seem to remain in the stream until they are a year 

 old and in some cases two years old, after which they go down 

 stream to the nearest large body of water whether a lake or a large 

 cold river. The majority of rainbows taken in a small stream out- 

 side of the spawning season are from 4 to 8 inches long, although 

 in exceptional cases a few up to one foot long have been captured. 

 But the larger, heavier fish are rarely if ever taken in brooks except 

 during or just after the spawning season in April and May. 



" Now if rainbow-s are planted in small streams which have no 

 immediate connection with a lake or large cold river, they are sure 

 to leave the stream permanently before they are large enough, to 

 furnish good sport, but if a large cold lake is available the larger 

 fish will spend most of the year in the lake, returning to the brooks 

 in spring to spawn. Thus it is hardly worth while to plant rain- 

 bows in streams which do not flow directly into some lake or cold 

 river or in those where the ascent of trout in spring is blocked by 

 impassable falls." 



There appears to be some inconsistency in what Embody says 

 concerning requisite conditions for rainbow trout. The statement 

 that they will live in waters where the temperature ranges upwards 

 of 85 degrees and possibly in lower oxygen content than the brook 

 trout is not exactly in accord with the statement that it is hardly 

 worth while to plant rainbows in streams which do not flow directly 

 into some lake or cold river. The latter statement, however, agrees 

 with Bean's remark that the rainbow seems to show a tendency to 

 work downstream. The belief in this tendency is traditional and 

 almost proverbial. For many years the idea that the rainbow would 

 not only stand but requires warmer water than the brook trout has 

 been prevalent, but some fish culturists have taken exception to 

 this generally accepted rule. As long ago as 1886, the first noted 

 success in acclimatization of rainbow trout was announced as hav- 

 ing been accomplished in streams of the Ozark Mountains region. 

 An inspection of Spring River, a tributary of the Arkansas, showed 

 that at least three generations of trout were present as the result of 

 a plant of fry in 1880. The largest fish observed weighed between 

 four and five pounds. The second in size measured 15 to 17 inches, 

 while the sources of the stream swarmed with thousands of young 

 from 4 to 5 inches long. Of the streams it was stated that they 

 were " clear and cold, the temperature of the water not rising above 

 58 degrees in the heat of summer." (Bull. U. S. Eish Commission, 

 Vol. 6, 1886, pp. 447-448.) 



A -former Commissioner of Pennsylvania (Meehan, '95) wrote: 

 " The rainbow trout early attracted the attention of the. government 

 authorities engaged in fish culture, and they felt the desirability^ of 

 transplanting the species into eastern waters. While this was a 

 laudable sentiment they fell into an error which, being spread broad- 

 cast, for several years and even yet to some extent caused and is 

 causing much useless labor in stream planting. Einding the rain- 



