Jaclyn Giovis Wolff
Metropolitan Water District Study Reveals Endangered Winter-Run Chinook Salmon Rely on Diverse Rearing Habitats
Research Effort Underscores the SWC and Member Agencies’ Commitment to Scientific Advancement
Sacramento, CA – A new study conducted by the Metropolitan Water District of Southern California (MWD) and a team of scientists from partner agencies and organizations reveals new information about the endangered winter-run Chinook salmon’s migration patterns and offers new insight into their protection.
MWD, the largest member of the State Water Contractors, partnered with the University of California, Davis, the NOAA Fisheries Service and the Lawrence Livermore National Laboratory on the research, which was published in the journal Biological Conservation. The study found that juvenile winter-run Chinook are venturing beyond the Sacramento River, using the river’s many tributaries to seek food and shelter on their way to the Pacific Ocean— challenging conventional wisdom around the species’ rearing tendencies.
“This study is a great example of how collaboration between academia and government agencies is advancing what we know about our complex ecosystems,” said Jennifer Pierre, general manager of the SWC. “Our respective approaches and resources complement each other, and the findings of this groundbreaking study speak to the potential for future partnerships to better understand California’s water and its species.”
The study is part of a larger effort by the SWC and its member agencies to increase scientific understanding of the Sacramento-San Joaquin Delta and its tributaries and species to solve some of the state’s water supply challenges. Each year, the SWC is investing more than $1 million in these efforts, laying the groundwork for new research that will spur policymaking in California and across the country.
The Chinook salmon research found that, on average, about half of the adult salmon that successfully reach the ocean and return to the river to renew the lifecycle ventured outside their natal reach of the Sacramento River as juveniles. While habitat restoration has typically been focused on the Sacramento River — the Chinook’s primary home — the new study highlights the potential for increased conservation opportunities beyond the Sacramento River.
“This research gives us a more comprehensive picture of the species’ migration patterns and survival strategies,” Pierre said. “With this information in hand, California can continue to refine and improve its habitat restoration efforts to yield better outcomes for endangered species like the Chinook salmon while gaining knowledge that can lead to improved water management policies and practices.”
The State Water Contractors is a statewide, non-profit association of 27 public agencies from Northern, Central and Southern California that purchase water under contract from the California State Water Project. Collectively the State Water Contractors deliver water to more than 25 million residents throughout the state and more than 750,000 acres of agricultural land.