100 REPORT OF THE SECRETARY OF COMMERCE 



During the fall and winter the majority of the larger shrimp dis- 

 appear from their usual grounds, probably moving off-shore to deeper 

 and warmer waters of the Gulf. Plans have been developed, there- 

 fore, through additional appropriations made by the last Congress, 

 to equip the Bureau's motor ship Pelican for off-shore experimental 

 fishing. It should be possible to determine whether this deep-water 

 concentration occurs, and whether or not the shrimp congregate in 

 sufficient quantities in these areas to make a commercial fishery 

 feasible. 



Paci-fic coast and Alaska fishery investigations. — Commercial fish- 

 ery investigations on the Pacific coast and Alaska are confined mainly 

 to the salmon and the herring. In the Pacific Northwest States the 

 studies directed toward the management and conservation of the 

 diminishing runs of sockeye salmon in Puget Sound and the Fraser 

 River area and the runs of all species of salmon in the Columbia 

 River (discussed previously) were continued; and in Alaska con- 

 tinued observations were made on the success of reproduction of red 

 salmon in the Karluk River and the pink salmon and herring in 

 southeastern Alaska. In addition a new and much needed investiga- 

 tion to measure variations in yield in the salmon fisheries of Alaska, 

 dealing with the collection and analysis of daily catch records for 

 the various types of fishing gear, was carried out during the past 

 year. 



In Puget Sound special attention has been given to a study of the 

 sockeye salmon population spawning in the Fraser River and the 

 coho salmon, the most important game fish in the Pacific Northwest. 

 The trend of the sockeye salmon fishery at sea and in the sound has 

 been studied by the collection and analysis of records of the com- 

 mercial catch since 1915. This study will establish a solid foundation 

 for active management of the fishery by the commission to be formed 

 under the authority of the recently approved treaty between the 

 United States and Canada. Observations on the life history of the 

 coho salmon in Puget Sound have been conducted to determine 

 changes in abundance and their underlying causes and to develop 

 methods of rehabilitation of populations in streams now barren or 

 depleted. Experiments have been conducted to determine the strength 

 of the homing instinct by transplanting hatchery reared fish. Ob- 

 servations on rate of growth of fingerlmgs have also been made in 

 different tributaries and extensive records have been obtained from 

 both the commercial and sports fisheries to indicate the drain on the 

 resource by these fisheries. 



In Alaska the extensive series of observations over many years on 

 the red salmon runs of the Karluk River on Kodiak Island have been 

 continued to discover factors influencing the success of natural propa- 

 gation in an attempt to forecast future runs more accurately. An- 

 other marking experiment was 'initiated in which nearly 50,000 

 fingerlings were marked by the amputation of a combination of fins. 

 The commercial catch of the region was carefully observed to obtain 

 records of marked adults returning from previous experiments. Dur- 

 ing the year complete returns from the 1929 spawning year were ob- 

 tained. The escapement was 900,519 which bore a ratio to the 

 spawning population of that year of 1.0 : 1 as compared with 2.2 : 1 

 for the 1928 escapement, and 1.8 : 1 for the 1927 escapement. This 



