As of 12/13/18, Sonoma Water Fisheries biologists have observed a total of 1,146 Chinook at the Russian River Fish Ladder at the Mirabel Inflatable Dam.
Previous Year's Totals
2017-2018 - 2,073
2016-2017 - 1,062
2015-2016 - Sonoma Water did not operate the Mirabel video monitoring system during the 2015/2016 season due to construction at the Mirabel Inflatable Dam.
2014-2015 - 1,432
It is important to note that this number of observed fish does not represent the total number of fish migrating past the dam, as only one side of the river currently has an operational video monitoring system. Given the data gaps due to recent storms and non-operation of the east-side fish ladder video system, it’s very difficult to compare this year’s counts to previous seasons. Our current count at Mirabel could easily be 50-100% off from the actual number of fish that have passed through the ladder.
Below is a graph comparing Chinook salmon counts from the video monitoring system from prior years.
Per the Biological Opinion and State Water Resources Control Board Order, the video counting system operated continuously at both fish ladders (on either side of the dam) as flows permitted. Sonoma Water biologists and a team of technicians review the time lapse images seven days a week and visit the site daily to clean and maintain the cameras.
Chinook salmon currently returning to the River are offspring of wild parents that spawned naturally in the upper 75 miles of the mainstem or in Dry Creek. Unlike many steelhead and coho salmon in the Russian River, there is no hatchery production of Chinook salmon. Fish returning to spawn are two to four years old. Spawning typically commences in November and continues through January. Eggs incubate in the gravel for roughly two months before fry emerge and begin their downstream migration to the estuary. Sonoma Water trapping and marking studies have shown that most juvenile Chinook salmon enter the Pacific Ocean by July of their first year of life.
Poor ocean conditions that led to low food supplies for juvenile fish in 2005 and 2006 negatively affected the abundance of adult salmon returns in 2007 and 2008 - hence the recent fishery closures along our coast. Sonoma Water has been monitoring Russian River Chinook for the past 13 years. In 2008, Sonoma Water counted only 1,113 fish - our lowest total to date. In 2012, Sonoma Water counted nearly 6,700 fish.
- View detailed data for past years chinook video monitoring (PDF)
- Historic Accounts, Recent Abundance, and Current Distribution of Threatened Chinook Salmon in the Russian River, 2007 (PDF)
We Need Your Help
Recovering Chinook salmon in the Russian River will require the participation of everyone in our community. If you observe any active Chinook poaching or suspicious activity, please notify the Sheriff's Department at 707.565.2121.