Fish Culture in Inland Waters 317 



Dr. Fasten mentioned another undesirable condition which might 

 arise from congested conditions within a stream. That is, a rapid 

 spread of any parasitic infection which happens to make its appear- 

 ance among the fish, and he indicated that parasitism might be 

 engendered under " closed down " conditions, in that the undis- 

 turbed shores would afford a habitat for fish-destroying birds and 

 other animals which not only kill large numbers of fish, but may 

 also be the means of disseminating various parasitic organisms 

 among them. 



Protective Methods. Bean ('16) wrote: "The strongest ally 

 of stocking is protection. Without the latter, the former will 

 quickly be nullified. The game protective force is constantly on 

 duty to prevent illegal fishing in all of its forms, and accomplishes 

 results which place it in the front rank among similar organizations 

 in this country. It should be understood, however, that fully 

 efifective protection is dependent upon public cooperation. The force 

 of any law is determined largely by the sentiment of the community 

 to which it applies, and in a community which does not countenance 

 game law violations the violations are relatively few. In accord- 

 ingly behooves everyone interested in better fishing to foster the 

 development of a clean and sportsmanlike spirit regarding the 

 observance of the fishing laws. Without such moral support and 

 active cooperation on the part of sportsmen, the 450 square miles 

 which every protector must police on the average cannot be 

 thoroughly supervised. It should be realized by those who are 

 doing the stocking that it is quite as important to effectively protect 

 their fish after they are in the water as to place them there properly 

 at the start." 



Laws intended to protect fish should be based upon positive 

 knowledge concerning the fish to be protected. Unless they are 

 framed in accordance with such knowledge, no matter how rigidly 

 and thoroughly they are enforced, they are liable to fail of their 

 object, and even result in harm to the fish for the protection of 

 which the law is enacted. 



It is generally conceded that fish should be protected during their 

 breeding season. Yet there are those who maintain that it is 

 no more harm to kill a fish during that season than at any other 

 time. They say an intensive fishery at any season destroys just as 

 many eggs and consequently progeny as if they were all caught 

 in the breeding season. This is false reasoning as applies to fish 

 in general. It is true that commercial fisheries for certain kinds of 

 fish are conducted profitably only at the time the fish are on the way 

 to the breeding places, and if the fishery were prohibited none of 

 those fish would be available for food. But there are many examples 

 of depleted fisheries which are attributable to too intensive fishing at 

 that time. 



It is easily seen why this is so. It is quite clear that if no fish 

 are produced to take the place of those caught the future supply is 

 reduced. Fish hatcheries are supposed to remedy this situation. 



