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How the Salmon Spawn Works

Where Salmon Spawn

Out of every 1,000 eggs laid, only about one survives to return to the home stream­ for the spawn. A large female salmon may lay as many as 5,000 eggs in multiple redds during the spawn, which can last between 30 and 40 hours. The fish you are angling for is healthy and a fighter, or it would have died sooner [sou­rce: Evergreen].

Salmon are prone to spawn in parts of the stream where the young fry can grow safely. This also ensures that the fry don't need to travel very far when looking for rearing areas. Most salmon are very adaptable to all freshwaters. They prefer clean, cool water that offers woody debris as well as clean spawning gravel. The table below shows how several species use different segments of rivers and streams. Salmon that have adapted to living in both freshwater and saltwater are called anadromous.

Pacific Salmon Species' Use of Northwest Waterways



Preferred Spawn Location


Lower reaches of small streams


Middle reaches of small streams; small tributaries of big rivers


Mainstem and larger tributaries of big rivers

Pink salmon

Lower reaches of big rivers

[source: Washington Department of Fish and Wildlife]

Where have all the salmon gone?
In the spring of 2008, wild salmon appeared to have abandoned sections of the Pacific coast, leaving professional anglers and guides stymied. Between 2005 and 2008, the number of salmon returning to the Sacramento River dropped from more than 800,000 to below 200,000, a loss of more than 75 percent. Although researchers identified more than 40 different possible factors --from hungry sea lions to water taken out of the river for irrigation -- no one was certain of the cause [source: CBS].

­Both pink and chum salmon have adapted to migrating to saltwater immediately after hatching rather than growing in the freshwater stream as other salmon species do. This technique allows the salmon to escape the higher mortality rate suffered by the species that remain in a more varying freshwater location [source: Evergreen].

Different varieties of salmon are found on both coasts and have been introduced into other locations as well. For example, several New York state streams have been stocked with Pacific salmon, primarily Chinook and Coho [source: Moore].

What are your options for salmon fishing during the spawn? Let's move upstream to find out!