26 U. S. BUREAU OF FISHERIES 



importance has been the extent, direction, and rate of the oceanic 

 migrations of the fish, with particular reference to the relationship 

 of the tish taken in Bristol Bay to those taken near the extremity 

 of the Alaska Peninsula. In an effort to solve this problem the 

 bureau, during 1922, tagged 4,000 red salmon — mainly in the region 

 south of the peninsula but close to the extremity. The details of 

 this work were given in the last annual report of this division. 



These experiments were continued on a larger scale during the 

 summer of 1923. Ten thousand fish were tagged from the large 

 fishing traps located along the south shore of the Alaska Peninsula 

 close to its extremity and from traps in the Shumagin Islands. 

 Scales were taken from each individual as it was tagged and liber- 

 ated. Most of the fish tagged were red salmon, though a few hun- 

 dred humpbacks, dog salmon, and silver salmon were also used. 

 The work Avas conducted by Dr. C. H. Gilbert and W. H. Rich, 

 assisted by W. P. Studdert. 



The results confirmed in every important respect those obtained the 

 previous year, and gave much additional information. Again a 

 large proportion of the fish tagged were taken in Bristol Bay, prov- 

 ing beyond doubt that the run of fish, which is of such commercial 

 importance along the southern shore of the Alasaka Peninsula, is 

 composed in large measure of fish bound for Bristol Bay. Their 

 home streams are located in the Bristol Bay district, and they are on 

 their return migration to the streams from which they came at the 

 time they are taken commercially. Apparently the feeding gTounds 

 of these salmon during their life in the ocean is along the continental 

 shelf of the North Pacific. Evidence is available which shows that 

 the fish found south of the peninsula pass through Isanotsky Strait 

 on their way to Bristol Bay. 



The rate of travel is approximately 20 miles per day during the 

 early part of the season, but this increases during the season imtil 

 the rate is nearly double this toward the end of the season, the latter 

 part of July. The rate of travel is apparently slower to near-by 

 streams and faster to more distant regions, such as Bristol Bay and 

 Cook Inlet. 



In addition to the migration to Bristol Bay, some of the salmon 

 are bound to local streams along the southern shore of the peninsula, 

 and to a less extent to local streams along the northern shore. An 

 interesting feature of this local migration is that the fish bound for 

 these local spawning grounds apparently school separately from those 

 bound for Bristol Bay. This is particularly indicated by the fact 

 that in Morzhovoi Bay, the first large indentation of the southern 

 coast of the peninsula east of Isanotslcy Strait, the fish tagged along 

 the western a,nd northern shores of the bay were predominately 

 Bristol Bay fish, while those tagged along the eastern shore during 

 the latter part of the season went mainly to local spawning grounds 

 to the eastward. A few of the fish tagged in the region about the 

 Shumagin Islands went eastward as far as Chignik, Kodiak and 

 Afognak Islands, and Cook Inlet. 



In addition to the scales collected from the tagged fish extensive 

 series of scales and measurements were made from fish taken for 

 commercial purposes in Bristol Bay, along the Alaska Peninsula, 

 and on Kodiak and Afognak Islands. Many of these scales have 

 been examined and the results are being correlated with the results 



