206 TWELFTH ANNUAL REPORT OF THE 



uncertain, and, sometimes, unprofitable. Pollution of streams by factory 

 and mill refuse is another fruitful cause of mortality among fishes. The 

 formal reports of State and Federal Commissions and Bureaus are full 

 of statements showing the deleterious effects of the introduction of acids, 

 alkalies, sawdust, and other substances which destroy water life. There ia 

 no excuse for this state of affairs, as it is perfectly feasible to dispose of 

 sewage and poisonous waste without allowing them to enter the streams. 

 This is done in many foreign countries and in some parts of our own land, 

 in fact such waste materials are often made a source of profit by conversion 

 into fertilizers and other useful articles of commerce. 



At Caledonia, the brown trout fry could not be induced, at one time, 

 to feed upon liver, the only food generally in use at the station, and some 

 mortality occurred through starvation. Believing that young fish would 

 take crustacean food if properly prepared for them, Foreman Redband 

 was advised to collect a lot of fresh water shrimp, grind them up minutely 

 and offer the juices thus prepared to the fry in the troughs. This sugges- 

 tion was carried out, and in a very short time the young began to take 

 shrimp juice freely, the mortality was checked and the trouble was soon 

 ended. 



There has been considerable discussion of the policy of planting brown 

 trout in State waters. The attitude of the present commissioner on this 

 subject is unfavorable to the introduction of brown trout into waters which 

 the brook trout now inhabits, He does not consider it desirable to liberate 

 brown trout in such waters, because it is a much larger fish, growing far 

 more rapidly than the brook trout, and soon driving away or destroying 

 its smaller relative. It appears to be perfectly proper to stock with brown 

 trout such waters as have become unsuitable and therefore no longer contain 

 brook trout. There is room in State waters for both species, and each has 

 its own advantages. Public sentiment will never abandon the brook trout 

 which has long held a high place in the affection of the angler and nature 

 lover. 



Food for Trout. 



This may be either natural food such as grows in trout waters, or it 

 may be artificial or prepared food including liver and other animal substances 



