CDFW Injects Chinook Salmon Eggs Into North Yuba

DOWNIEVILLE — On Wednesday, the California Department of Fish and Wildlife injected 212,000 chinook salmon eggs into the bed of the North Yuba River near Downieville at five separate sites. The step marks the second year of the Yuba Salmon Study pilot program, which is reintroducing spring-run chinook salmon to the North Yuba River after the construction of the Englebright Dam more than 80 years ago.

The study, led by the California Department of Fish and Wildlife (CDFW), already successfully planted salmon roe last year, with juvenile chinook being captured downstream in rotary screw traps during the spring. The CDFW then released the fish below the Englebright Dam to continue on their way to the ocean. After three to five years maturing in the ocean, the salmon will return to the waters below the Englebright, where they will be captured and transported back above Bullards Bar Reservoir. From there, the salmon can continue on to their spawning grounds near Downieville to continue the cycle.

Recently, the CDFW also introduced 42 adult salmon to the river, one of which was caught by a young angler near Rocky Rest Campground in October. The release marked the first time adult spring-run chinook have been reintroduced above a rim dam in California, which the agency views as a “landmark achievement for salmon recovery in the state.”

The CDFW team at Wednesday’s planting built on techniques used last year. The group used a water pump to clear nests of silt, allowing members to plant eggs up to 1.5 feet into the gravel. The techniques mimic how adult chinook would spawn in the river naturally. The team hopes the approach will give roe the highest chances of hatching into viable juveniles. At a site near Goodyears Bar, a team including Reintroduction Supervisor Michelle Forsha and Program Manager Colin Purdy injected 45,000 “eyed up” eggs—eggs where the eyes of the fish are visible—into a flat and wide section of the river.

A rotary screw trap fishing the North Yuba at Rocky Rest Campground will be ready to capture juvenile chinook after they hatch. While getting an estimate of survival rates for the eggs is difficult, sites with “hatching boxes” that allow teams to count spawns have shown survival upwards of 90%, according to Purdy. Hatchlings will begin to show up in traps early next year, but some don’t migrate from their spawning grounds until much later.

While the pilot program is still in its early stages, the project has been successful in reintroducing king salmon to waters they haven’t been able to access since 1941. Although there are no plans to allow the fish to naturally bypass the Englebright and Bullards Bar dams, the study remains a priority for Governor Gavin Newsom’s administration under his “California Salmon Strategy for a Hotter, Drier Future.”