The Sauk-Suiattle Tribe is studying how climate change will affect members of the tribe and the natural resources that sustain them.

“The tribe values a healthy river as equal to a healthy and vibrant human community,” said Jason Joseph, Sauk-Suiattle natural resources director. “This project will be a case study of sustainability in the face of global warming. We’re focusing on the effects on fisheries and reservation infrastructure.”

The homes and administration buildings of the Sauk-Suiattle reservation are on the banks of the Sauk River near Darrington. With nearly 400 glaciers in the region, the Sauk and other tributaries to the Skagit River – the Suiattle and Whitechuck – will see rapid change as the climate continues to warm.

“Our predictive model will take information from many places, starting with glacier recession and changes in snow elevation already under way, and projecting those into the future,” said Robert Franklin, Sauk-Suiattle fishery program manager. “As glaciers disappear and no longer contribute cold melt water in the summer, temperatures will rise, getting too warm for fish and making it more difficult for them to survive and grow.”

Winter floods also will be larger and more frequent.

The tribe is using the global climate model, which is widely used for weather forecasts and projecting climate change. “We’ll look at erosion rates as the channel migrates, and get a prediction for how quickly the river will overtake reservation land,” Franklin said.

The tribal natural resources department is holding a community meeting to get input from tribal members about their concerns.

“People have already seen things happen,” Franklin said. “A bridge washed out on the Suiattle in 2006. We had record floods in 2006 and 2009. We want to make sure we’re focusing on the things that matter to them, so that people will be able to make use of this study.”

By predicting changes to the channel, floodplain, flows and water temperatures, fisheries managers can identify populations that are most vulnerable to climate change. For example, the eggs of fall-spawning salmon could be threatened by faster, higher flows if the snowfall no longer melts slowly, and instead becomes rain that enters the river right away.

“If we identify that certain runs of chinook are vulnerable, that should influence our approach to restoring them and harvesting them as we face what we can’t stop,” Franklin said. “We also can use the predictions for flood risk to plan and redesign buildings, utilities and roadways around the reservation.”

The study is supported by a federal Environmental Protection Agency grant made available through the Puget Sound Partnership, and a partnership with the U.S. Geological Survey and Natural Systems Design, Inc.

For more information, contact: Robert Franklin, fishery program manager, Sauk-Suiattle Tribe 360-436-0347 or rfranklin@sauk-suiattle.com; Kari Neumeyer, information officer, NWIFC, 360-424-8226 or kneumeyer@nwifc.org.