A 2024 paper published in San Francisco Estuary and Watershed Science notes that tidal wetland restoration for at-risk fish has gained momentum over the past decade. All young creatures need a safe place to grow up, and baby salmon are no exception. One project in California’s Delta is using the tide to create that habitat. Dutch Slough, a site near Oakley, is one such effort.
The goal is to turn retired farmland into tidal marsh that offers juvenile salmon and other species safer habitat. Salmon spawn upstream and their young move downstream in search of food and shelter . It calls for more study of fish use of restored habitats. It also suggests better monitoring and adaptive management. Restored and reference channels offered similar foraging and growth potential for juvenile Chinook salmon. However, densities of salmon were reduced in restored channels. The authors concluded that some habitat features are recoverable quickly, but not all are. Also, it improves water and air quality, and he called the site a living laboratory for studying future wetlands.
The 2024 paper summarizes a fall 2023 symposium hosted by DWR and the State Water Contractors. A 2014 study in Transactions of the American Fisheries Society examined a similar project in Washington State. Tidal flow returned to 364 hectares (about 900 acres) of marsh at the delta of the Nisqually River. DWR says it must plan for climate hazards while serving clean water to 27 million Californians.
Because the water was warmer and less stable, the growth potential was more variable.
“It’s essentially a safe neighborhood for fish,” said Patty Finfrock, DWR’s project manager for Dutch Slough at the time. DWR Deputy Director Kristopher Tjernell said the project advances scientific knowledge. He said it also benefits fish and wildlife that have suffered for decades from land and levee development.
