Survivor salmon that withstand drought and ocean warming provide a lifeline for California Chinook

In drought years and when marine heat waves warm the Pacific Ocean, late-migrating juvenile spring-run Chinook salmon of California’s Central Valley are the ultimate survivors. They are among the few salmon that survive in those difficult years and return to spawning rivers to keep their populations alive.

Survival of Migrating Juvenile Salmon Depends on Stream Flow Thresholds

New understanding of relationship between stream flows and salmon survival provides a critical tool for balancing water needs in the highly managed Sacramento River.

A threshold defined as the “historic mean” flow of 10,712 cubic feet per second (cfs) provides an especially important target for resource managers, said Cyril Michel, associate project scientist in the Fisheries Collaborative Program at UC Santa Cruz.

Scientists Describe ‘Hidden Biodiversity Crisis’ as Variation within Species is Lost

Many of the benefits people receive from nature depend on diversity within species, but this intraspecific variation is poorly understood and declining rapidly.

“Biodiversity means more than the number of species, and when we focus on species-level extinctions we are missing part of the story,” said corresponding author Eric Palkovacs, professor of ecology and evolutionary biology at UC Santa Cruz.