Description
Pacific salmon are an important biological and economic resource of countries of the North Pacific rim. They are also a unique group of fish possessing unusually complex life histories. There are seven species of Pacific salmon, five occurring on both the North American and Asian continents (sockeye, pink, chum, chinook, and coho) and two (masu and amago) only in Asia. The life cycle of the Pacific salmon begins in the autumn when the adult female deposits eggs which are fertilized in gravel beds in rivers or lakes. The young emerge from the gravel the following spring and will either migrate immediately to salt water or spend one or more years in a river or lake before migrating. Migrations in the ocean are extensive during the feeding and growing phase, covering thousands of kilometres. After one or more years the maturing adults find their way back to their home river, returning to their ancestral breeding grounds to spawn. They die after spawning, and the eggs in the gravel signify the beginning of a new cycle. Upon this theme Pacific salmon have developed many variations, both between as well as within species.
Pacific Salmon Life Histories gives detailed descriptions of the different life phases through which each of the seven species pass. Each chapter is written by a scientist who has spent years studying and observing a particular species of salmon. Some of the topics covered are geographic distribution, transplants, freshwater life, ocean life, development, growth, feeding, diet, migration, and spawning behaviour. The text is richly supplemented by numerous maps, illustrations, colour plates, and tables and there is a detailed general index, as well as a useful geographic index.
This volume brings together for the first time, and in a comprehensive form, most of the available biological information on the seven species of Pacific salmon. It is an invaluable source of information for students and teachers of biology and fisheries science, people in the fishing and aquaculture industry, and interested laypersons in countries of the North Pacific and elsewhere.
