Native salmonids (Rainbow/steelhead trout, Bull Trout, Dolly Varden) populations in the upper Skagit River have a complex evolutionary past shaped by geology, hydrology, and human actions. In our latest research study funded by City Light, we’re using genomic tools to unravel the phylogenetic biogeography of Rainbow and Bull Trout in the upper Skagit River basin.

The current drought (up through 2016), in combination with other long-term stressors, is threatening survival of Sacramento River winter-run Chinook Salmon population. Given the circumstances, data on vital rates for the population are urgently needed to better guide management efforts.  The study directly links adults and offspring (within brood year) using genetic mark-capture, parentage, and […]

Project Need Average yearly false positive rate for winter run (i.e. calling a fish winter run when it wasn’t) at South Delta diversions fish protection facilities (salvage) during 1996-2010 was 56%, although error rates varied considerably within a season.  For 2011-2014, average yearly false positive rates at the CVP salvage have been 58% – 80%, […]

A primary goal of the Central Valley Project Improvement Act (CVPIA) is to double natural production of Chinook salmon in California Central Valley streams through restoration actions that involve both non-discharge (e.g., gravel augmentation) and discharge (e.g., flow management) components.  Quantifying these benefits has been hindered by the inability traditional sampling techniques to identify juveniles […]

Read the peer-reviewed publication Overview Present monitoring programs were not designed to derive population estimates of Delta smelt. Thus, estimating Delta smelt annual population size (N) has proven challenging due to difficulties in estimating gear efficiencies and sampling in all potentially occupied habitats.  Additionally, reliance on an abundance index has hindered the ability to evaluate the role […]