American shad — the Delta’s most-abundant and least-considered anadromous fish

American shad are the Chinook salmon of herring. Like Chinook salmon, adult American shad spend several years in the ocean before returning to rivers for spawning — they’re anadromous. Also, like salmon, anglers love shad because they’re fun to catch and good to eat. Well, okay, shad are not as good to eat as ocean caught salmon, but they are delicious when prepared well.

American shad are native to the east coast of North American. They were introduced to the Sacramento River after repeated releases of shad fry — transported via the then newly completed transcontinental railroad — between 1871 and 1880. Shad quickly became abundant in the Sacramento River and proceeded to colonize many other rivers along the West Coast. In the Columbia River system, shad are now the most abundant anadromous fish species migrating upstream through impoundments on the lower Columbia River. At Bonneville Dam — 140 river miles upstream of the Columbia River mouth — an average of 2.2 million adult shad migrated upstream each year between 1992 and 2003. In contrast, an average of 940,000 adult salmonids migrated annually past Bonneville Dam during the same period.