PROGRESS IN BIOLOGICAT. INCill IRIES, litli'.' 



093 



Avill be of the utmost value in the formulation of coiis-rvation meas- 

 ures which will both insure the maintenance of these j^ioat natiiial 

 resources and, at the same time, allow the maxinmm catch f(ir 

 commercial pur})oses. 



The study of conditions on the spawning grounds at Karluk Lake 

 was continued by W. H. Rich and M. W. Brown. The lake was vis- 

 ited in July and again early in September. Physical conditions a])- 

 peared to be satisfactory so far as temperatures and water supply were 

 concerned, but, on account of the very poor escapement, the spawning 

 grounds were seeded more sparsely than in any year since regular 

 observations were started. A fairly good escapement was reported 

 during September, however, and it may be that this will be sufficient 

 to produce a moderate run in 1984 — the year in whicli most of the 



Figure 5.- 



-A salmon counting weir in Alaska. Enumerators count each fish that 

 passes through the opening shown in the foreground 



progeny of the 1929 escapement will return as adults. Otherwise the 

 prospects for 1934 are by no means bright. In addition to observa- 

 tions on the spawning grounds, plankton samples and temperature 

 records were secured wliich have been submitted to Prof. Chancey 

 Juday of the University of Wisconsin for study. 



Ghignlk River' investigations. — An intensive investigation, similar 

 to the one at Karluk, is in progress at Chignik by H. B. Holmes. 

 As at Karluk, this investigation has for its chief objective the de- 

 termination of the relation between the number of fish in the spawn- 

 ing escapement and the resultant number of mature fish. 



The irregularities in the life history of the fish that cause diffi- 

 culty in scale interpretation are confined to the time the fingerlings 

 spend in fresh water before migrating to the ocean. A study of 

 this part of the life history was started in 1928. 



