106 



THE MIGRATION AND CONSERVATION OF SALMON 



would reduce the catch per boat. The pres- 

 ent area extends from a point directly 

 south of Port-aux-Basques towards Cape 

 Ray. Certainly you could not double the 

 number of fishing boats on this area with- 

 out diminishing the catch per boat. How- 

 ever, no one knows how extensive an area is 

 available for fishing. 



Nature has imposed certain limitations. 

 The fishing is early, starting around the 

 first of May. The ice sometimes does not 

 go out until the last week in April. Also, 

 the weather conditions are such that it is 

 impossible to fish every night and severe 

 weather necessitates the use of a short 

 "fleet" of drift-nets. The expansion of the 

 Port-aux-Basques drift-net fishery depends 

 upon whether there is sufficient available 

 territory and whether the weather condi- 

 tions are favorable over a period of years. 



The fishery started about 1931, only three 

 or four boats being engaged for the first 

 four years. The number jumped to 17 in 

 1935. As a result of the extremely profita- 

 ble season the number of boats increased to 

 32 in 1936. The 1936 season proved dis- 

 astrous, most boats hardly making enough 

 to pay expenses, and as a result there were 

 only 24 boats that fished the whole season 

 in 1937. 



Mr. Menzies. It is no worse to catch a 

 salmon spawning than in the sea. 



Dr. Belding. Probably there is greater 

 damage in taking the spawning salmon be- 

 cause it has already run the gauntlet of the 

 commercial fisheries and the anglers. 



Mr. Menzies. The only difference is in 

 the salmon 's expectation of life, whether he 

 is killed on the spawning ground or at Port- 

 aux-Basques, 



Summary 



The salmon of a given species may in a 

 locality, e.g., a river, constitute a more or 

 less distinct entity, for which the name 

 ''stock" is to be preferred. It is not known 

 whether the differences between such local 

 stocks are ever heritable. 



Salmon from a given local stock are in 

 some instances at least to be found in the 



sea long distances (hundreds of miles) 

 from their river. It is not known whether 

 this is a regular behavior and associated 

 with feeding, nor is it known what propor- 

 tion of the stock has this behavior. 



Salmon, when in the sea, exhibit rather 

 marked differences in the distances they 

 travel after liberation. These differences 

 are seen as associated with relation to 

 rivers, but whether correlated with dis- 

 tance from natal river or with degree of 

 river influence is uncertain. 



Salmon return predominantly to their 

 rivers of origin, but it is not known what 

 proportions return, nor what conditions 

 determine return. 



Movement of salmon through a river 

 estuary and up a river is influenced by the 

 relative quantity of water flowing down- 

 stream, but the way in which this acts is 

 not known. 



Salmon (Atlantic) that have spawned be- 

 have differently, at least in some places, 

 from those that have not. 



Temperature is an important factor af- 

 fecting the movements of salmon, but the de- 

 tails of its effects may differ from place to 

 place and need elucidation. 



There are indications of the behavior of 

 salmon changing with the development of 

 sexual maturity, but more knowledge is 

 needed. 



The behavior of salmon depends to quite 

 an extent upon changing light conditions, 

 but the effects of light are complex and re- 

 quire clarification. 



It is not kno-wTi to what extent the move- 

 ments of the salmon are at random, to what 

 extent they are directed, nor how they are 

 directed. 



There is as yet no knowledge of the sense 

 of smell determining the salmon's move- 

 ments. 



Proof of any general decrease in the stock 

 of Atlantic salmon is lacking. It is impor- 

 tant (1) to have sufficient numbers of spawn- 

 ing salmon in the rivers to maintain the 

 local stocks, and (2) to assure the best con- 

 ditions in the rivers for the eggs and young. 



