The Idaho Power Company has set up receivers in key locations that will allow them to track these sturgeon over the next five years. We are already seeing some interesting movements from these fish. Of the 23 sturgeon released at Heller Bar, 11 have been detected moving to or past the next receiver nine miles upstream. One sturgeon made this 9-mile migration in one day and five days later reached the next receiver 12 more miles upriver. One fish that was released at Nisqually John migrated over 42 miles upstream to Heller Bar in seven days. So far, only one sturgeon released at Heller Bar has been detected in the reservoir (over 30 miles downriver). Much of the receiver data has not been downloaded yet, so I can’t tell you whether any of the fish migrated back downstream over Lower Granite Dam. The movement of these translocated sturgeon will be tracked for at least the next five years and will help us understand whether upstream translocation is important management tool that can be used to help rebuild and stabilize this sturgeon population.

Modeling

Just recently, the Idaho Department of Fish and Game and Idaho Power Company has contracted with a professor at the University of Idaho to develop a model that will estimate the long-term trend in abundance for the Hells Canyon sturgeon population. When completed, not only will this model be able to estimate long-term trends in sturgeon abundance, but we will also be able to plug in different management tools such as upstream and downstream translocations to evaluate whether these actions will be enough to rebuild and stabilize this sturgeon population. Our hope is that we will have a working model in under two years. 

What if Translocating Sturgeon is Not Enough?

I want to share one last figure with you as it shows a very concerning trend that I want you to be aware of. The bars in the figure below show the average flows during May through July in the Snake River at Anatone (near Heller Bar) from 1959 to present. The reason it displays average flows during May through July is because this is the time when sturgeon spawn, the eggs hatch, and the newly born sturgeon drift down into the reservoir. This is the time period when these young sturgeon are most vulnerable. The red- and yellow-colored bars are the years when we have data that indicates whether there was detectable recruitment or not (survival through this vulnerable time period). The red bars indicate years when we did not detect any successful recruitment, and the yellow bars are the years when we did detect successful recruitment. The blue bars are years when we don’t have data to evaluate recruitment.