INTRODUCTION 



Since salmon angling causes its devotees 

 to migrate from country to country for the 

 thrill it affords, the clubs on the salmon 

 rivers of northern New Brunswick and 

 Quebec are decidedly international in 

 character. It is not surprising, therefore, 

 that on becoming alarmed over decreases in 

 the stocks of salmon in these rivers, they 

 brought to their assistance Dr. D. L. Beld- 

 ing, of Boston, who had been prominent in 

 fisheries investigation in Massachusetts, Mr. 

 W. L. Calderwood, of Edinburgh, with a 

 life-time of experience with Atlantic sal- 

 mon, latterly as Inspector of Salmon Fish- 

 eries of Scotland, and Dr. Henry B. Ward, 

 of Illinois, noted for his studies on the be- 

 havior of the Pacific salmons. These clubs 

 shared a rather general belief that the sal- 

 mon of their rivers migrate to and from the 

 open Atlantic ocean through the Gulf of 

 St. Lawrence and past the Maritime prov- 

 inces and Newfoundland, where they would 

 be liable to capture. 



Failure of scientific agreement on this 

 matter at a conference with Canadian Gov- 

 ernment officials at Ottawa on February 7 

 and 8, 1936, not only stimulated investiga- 

 tion as well as discussion of the subject in 

 scientific journals, but also led to the pro- 

 posal by Dr. Ward that the migration and 

 conservation of salmon in general form the 

 subject of a symposium for the meeting of 

 the Association at Ottawa in June of 1938. 



All the invitations to participate in the 

 symposium were accepted and it was held 

 in the Chateau Laurier, Ottawa, on the 

 morning of June 29, 1938, although Drs. 

 Clemens, Foerster and Pritchard, of British 

 Columbia, were unable to be present in per- 

 son. As the time allotted did not permit 

 opportunity for discussion, the participants 

 were invited to meet the following day in 

 the office of Mr. J. J. Cowie, Secretary of 

 the Fisheries Research Board of Canada. 

 At this meeting, which lasted the entire day, 

 there was very free discussion of the con- 

 troversial matters dealt with in the sym- 

 posium. It was decided to include the more 



significant parts of this discussion in the 

 published account. 



Apart from its connection with the prac- 

 tical problem of getting sufficient salmon 

 for food and for sport, the migration of 

 these fish is of very great scientific as well 

 as general interest. Mass movements of 

 animals are often of such a striking char- 

 acter as to stimulate enquiry concerning the 

 forces behind them. In this as for nearly 

 any kind of animal behavior, scientists tend 

 to divide into two schools — those who ex- 

 pect the "nature" of the animal to afford 

 the explanation, and those who look for it 

 in ''nurture" or environment. Actually, 

 of course, both the animal and its environ- 

 ment are always involved, and the problem 

 is to determine the extent of the role played 

 by each. Disputed scientific points can best 

 be settled by precise experiments, but mi- 

 grations in the ocean and in the rivers 

 scarcely lend themselves to precise experi- 

 mentation. If at the same time the matter 

 is very complex, as seems probable, the 

 problem will not be readily solved. 



The migration of salmon may well be 

 taken to typify the migration of fish in 

 general as is seen by the prominent position 

 it has occupied in books on fish migration. 

 It is a very striking migration — from breed- 

 ing grounds in rivers, perhaps many miles 

 up most turbulent and swift streams, to 

 more or less unknown places in the sea, 

 where the main growth takes place. Where 

 are these places? What are the salmon's 

 movements thither and thence, and how are 

 these determined? To what extent do the 

 salmon return and spawn in the streams 

 where they are born ? Such questions have 

 been in the minds of the investigators, who 

 with diverse backgrounds of experience 

 have dealt, each in his own way, with the 

 migration of salmon in this symposium. 



The Salmon family (Salmonidae), as oc- 

 curring naturally, are confined to the coasts, 

 rivers and lakes of the Arctic and North 

 Temperate zones, which has long been 

 known, the most recent critical considera- 



