California has long trucked most of its young hatchery salmon around the Sacramento-San Joaquin Delta to avoid losing them to pumps, poisons and predators. This year, under pressure from fishing groups, it will truck nearly all of them – nearly 17 million salmon smolts.
Federal officials will also truck about 10 percent of the salmon produced at their hatchery near Redding. They haven't trucked fish in more than a decade, and then only as a test. This year, those fish will ride nearly 200 miles to reach San Pablo Bay.
The hatcheries were created to replace spawning habitat eliminated by dams. But this year's changes are prompting important questions about how the hatcheries themselves affect salmon survival.
Salmon Tags to Reveal if Hatcheries Help or Hurt
US - Hoping to engineer their way out of a salmon crisis, wildlife agencies are manipulating the natural rhythms of the species to an unprecedented degree in hopes of producing more fish.