THE MIGRATIONS OF PINK SALMON (ONCORHYNCHUS 
GORBUSCHA) IN THE CLARENCE AND SUMNER 
STRAITS REGIONS OF SOUTHEASTERN ALASKA 1 
By Frederick A. Davidson, Ph. D., Aquatic Biologist, and Leroy S. Christey, Field Assistant, 
United States Bureau of Fisheries 
J> 
CONTENTS 
Page 
Introduction 643 
Channels of migration 644 
Tagging methods 645 
Pink-6almon tagging experiments in Clarence Strait and adjacent waters, 1924-32 646 
Tagging experiments in the vicinity of Cape Fox 648 
Tagging experiments in the vicinity of Cape Chacon 649 
Tagging experiments on Gravina Island and in the vicinity of Kasaan Bay 651 
Tagging experiments in the vicinity of Cape Muzon 654 
Pink-salmon tagging experiments in Clarence Strait in 1935 and 1936 654 
Summary of Cape Chacon experiments 660 
Pink-salmon tagging experiments in Sumner Strait, 1924-36 661 
Tagging experiments at Ruins Point and Cape Decision 662 
Tagging experiments at Point Colpoys 664 
Summary of Point Colpoys experiments 665 
Conclusions 665 
Literature cited 666 
INTRODUCTION 
Southeastern Alaska lies on the Pacific shore of North America between latitudes 
54° and 60° N. It is composed of a narrow coastal strip and a broken chain of moun- 
tainous islands known as the Alexander Archipelago. The geography of that part 
which includes the Alexander Archipelago is illustrated in figure 1. Owing to the 
temperate climate and heavy rainfall of this region most of the islands and mainland 
shore are covered with dense growths of timber and are drained by hundreds of streams 
that range in size from brooks to small rivers. These streams support one of south- 
eastern Alaska’s most valuable natural resources in that they form the breeding 
grounds for millions of salmon that migrate into them each year to spawn. Through 
the utilization of these salmon a large and flourishing food-packing industry has 
developed which is providing nutritious food for the nation as well as a substantial 
income to the citizens engaged in it. 
The Pacific salmon of the genus Oncoribynchus spend part of their lives in the 
sea where they mature and part in the streams where they spawn and then die. The 
period during which the adults migrate from the sea extends from early summer to 
1 Bulletin No. 25. Approved for publication August 20. 1937. 
643 
