(Oncorhynchus nerka)
This species is next in commercial value to the chinook. It has been
taken occasionally in the Sacramento river but it is not common south
of the Columbia river. The run of this species begins about the first
of April and the fish go as far as Salmon river, Idaho, fully 1000
miles from the sea to spawn. By a peculiar instinct this species only
run up such rivers as have lakes at their heads, and spawn in the
lakes or at the mouths of little streams emptying into them, in many
of the lakes of Oregon and Washington are found the young of the
blue-back salmon which are commonly called redfish. These fish never
leave these lakes and therefore never attain a size of more than five
to seven pounds.
Head, short and pointed and light olive in color; under jaw, white;
body, long, slim and rather flattened; back, blue; sides, silver;
belly, dull white; dorsal fin, dark; others flesh color; tail, rather
narrow and well forked; gills, 13 to 15. As the spawning season
approaches the whole fish takes on a decided reddish cast, which
sometimes becomes as dark as a brick-red. The jaw becomes very much
hooked, and a few spots appear.