ATLANTIC SALMON 



43 



thoroughly with the ebb, they are swept out 

 to sea. 



The maturing salmon enter the Margaree 

 estuary through its narrow mouth follow- 

 ing a freshet, and ascend above the head of 

 tide under the same stimulus, although 

 how the freshet acts is not clear. They re- 

 main in the river only where they find pools 

 of sufficient size, particularly in depth. 



The smolt, the maturing salmon and the 

 kelt differ somewhat in nature, as shown by 

 the degree of response to changes in light 

 and in current. The movement that re- 

 sults, whether upstream or downstream, 

 depends not only upon the nature of the in- 

 dividual fish, but also upon the strength of 

 the physical stimulus to which the fish is 

 exposed. Only a small beginning has been 

 made in finding out details of the reactions 

 of the salmon and details of their physical 

 environment, which are needed to explain, 

 the movements in the river. 



Conservation 



Presumably the conservation of salmon 

 is for the purpose of assuring conxinued 

 maximum exploitation of the salmon by 

 man for food and sport. I do not know of 

 any general desire to have them preserved 

 either for man's pleasure in observing 

 them, as seems to be true for birds, or for 

 the maintenance of more desired forms of 

 life, as fish-eating birds might be consid- 

 ered to be. 



Conservation has received such general 

 and strong advocacy that it is seemingly 

 considered as desirable in itself apart from 

 any object it may originally have had. 

 That object should not be obscured or we 

 may be defeating our own ends. It is a 

 common mistake to generalize from a par- 

 ticular, unrepresentative case ; salmon con- 

 servationists constantly base their efforts 

 upon undoubted instances of man's having 

 done away with the entire salmon stocks in 

 certain rivers. The jump is then made to 

 efforts towards conserving the general stock 

 of salmon by restricting the netting of sal- 

 mon in the sea, by which means it is true 

 more salmon are captured than by angling 

 in the rivers. 



Such a procedure is decidedly unscien- 

 tific. It is well known that for the most 

 part each river has its own stock of salmon. 

 For this reason each river stock should be 

 considered by itself to ascertain (1) to 

 what extent it is being exploited and (2) 

 whether any proposed restriction of the 

 fishery will permit a larger yield in the 

 future. Until such questions are answered 

 we may, if we restrict the fishery, be like 

 the dog in the fable, ' ' drop the meat to seize 

 its reflection in the water." The unscien- 

 tific character of vague statements that net 

 fishing is endangering or will endanger the 

 stock of salmon should be recognized. I 

 have failed to find evidence that net fishing 

 in the open sea or on an open coast has 

 ever seriously reduced the stock of salmon, 

 and I believe it fairly certain that such fish- 

 ing would become quite unprofitable before 

 there was serious reduction. In narrow 

 estuarial waters and in the rivers, however, 

 man can rather readily reduce the numbers 

 of salmon to very low levels, and there is 

 the place of danger. From the standpoint 

 of mere conservation of the stock, it is de- 

 sirable that the salmon should not enter the 

 river until late in the season, unless they 

 are less likely to perish there. However, 

 for exploitation by anglers, they should en- 

 ter early in the season. Any use, in argu- 

 ment for conservation, of the numbers of 

 adult salmon taken by the commercial nets 

 or in angling may be quite misleading, 

 since the significant thing is reproduction, 

 the number of salmon that remain for 

 spawning, which may have a converse as 

 well as a direct relation to the number re- 

 moved by capture. Even the number of 

 salmon entering the river is no safe cri- 

 terion when the extent of poaching is not 

 accurately known. The net fishery, when 

 well and regularly prosecuted year after 

 year, seems to give very good evidence of 

 fluctuations in the stock, and accurate rec- 

 ords of the catch in such fishery are pro- 

 curable and valuable for following the 

 fluctuations. Apparently, however, there 

 can be wide fluctuations with always an 

 ample number of spawning individuals. It 

 is hardly wise to conclude that conservation 



