GWEN IFILL: Now: how a Native American tribe out West is adjusting to declining numbers of a traditional food staple, salmon, and the role of climate change in all this.
Our story was produced in collaboration with EarthFix, a project of KCTS Seattle that focuses on environmental reporting in the Northwest. And it's part of our Coping With Climate Change series.
Hari Sreenivasan reports.
HARI SREENIVASAN: The coastal tribes of the Pacific Northwest call themselves ‘Salmon People.’
BRIAN CLADOOSBY, Swinomish Indian Tribal Community: Salmon to the Swinomish Tribe is like the buffalo to the tribes in the Midwest. It is the food that the creator has blessed us with.
HARI SREENIVASAN: Every year, they hold ceremonies to bless fishermen and honor the returning salmon. But over the last century, the number of salmon making their way home has dropped significantly.
The Pacific King salmon is now an endangered species.
BRIAN CLADOOSBY: Can you imagine 200 years ago what it was like to be out here?
HARI SREENIVASAN: Brian Cladoosby is the chairman of the Swinomish Indian Tribal Community, which sits at the mouth of the Skagit River. His people have fished the shores of Puget Sound for as long as they can remember.
BRIAN CLADOOSBY: There was salmon in that slough here 365 days out of the year. Throughout the cycle of the year, there was a different salmon that was occupying those waters.
HARI SREENIVASAN: The fish were still plentiful in 1855, when Cladoosby's great-great-grandfather put his X. on a treaty. That treaty traded away most of their land in exchange for securing the rights for all Swinomish people to continue to fish, hunt and harvest shellfish in their historic grounds.
In the 150 years since, overfishing, loss of habitat and hydroelectric dams have depleted salmon populations throughout the Northwest. Low returns have forced tribes to reduce their fishing to a short window.
BRIAN CLADOOSBY: This year, we got three days for the whole year to fish Chinook.
HARI SREENIVASAN: And now there is another threat: Rising temperatures may push Northwest salmon to the brink of extinction.
Salmon depend on the glacier-fed streams of the Northwest to survive. But since 1920, the average annual temperature in the region has risen by one-and-a-half degrees. According to the United States Geological Survey, that slight rise in temperature caused the South Cascades Glaciers to shrink to half what they were a century ago.
Hydrologist Alan Hamlet, who works with the group, says the loss of those glaciers has many consequences.
ALAN HAMLET, University of Washington Climate Impacts Group: When we lose the snowpack in the mountains and the glaciers, those are a kind of water tower, a way of storing water under natural conditions. And when we lose that water tower, then the flows in the summer go down.
HARI SREENIVASAN: This means higher water in the wintertime and lower streams in the summer, a combination that he says spells disaster for salmon at every stage of their life.
Heavy winter floods can wash away salmon eggs and small young fish. And low summertime currents mean warmer water. Adult salmon die if water temperatures rise above 70 degrees. Hamlet and other researchers project that, by 2080, nearly half of the streams they monitor will exceed average weekly temperatures of 70.
ALAN HAMLET: All of these fish are very vulnerable to climate change, particularly from water temperature, but also from changes in flow and in the marine environment.
HARI SREENIVASAN: Estuaries like this one act as nurseries for young salmon. Here, they are protected from predators and can feed on eelgrass before heading out into the ocean.
Hamlet says these habitats may disappear as well.
ALAN HAMLET: We're expecting to see substantial sea level rise, perhaps a meter of sea level rise. And that will inundate this area, if nothing else changes.
HARI SREENIVASAN: After watching other tribal communities lose their homelands and traditional food sources, Cladoosby fears that his tribe will be next.
BRIAN CLADOOSBY: I'm not a scientist. I don't know why climate change is happening. I don't know if it's just -- if it's just a cycle in the Earth, you know -- it's a generational thing, or if there's too much pollution entering the atmosphere.
And so when we're seeing climate change impacts in our areas, we figure we better get ahead of the curve.
HARI SREENIVASAN: To get ahead of the curve, they became the first tribe in the country to conduct a comprehensive climate adaptation assessment, their aim, to meld their direct observations of the natural world with top scientific research.
Billy Frank Jr., who is the chairman of the Northwest Indian Fisheries Commission, says the native people recognize when the climate is out of sync.
BILLY FRANK JR., Northwest Indian Fisheries Commission: We know all about the ocean, we know the currents, and we know everything that's going on out here. We learn from the animals. We learn from the birds. We learn from our surroundings. You know, we learn from each other.
HARI SREENIVASAN: Ray Harris, a fisherman with the Chemainus First Nation on Vancouver Island, agrees.
RAY HARRIS, Chemainus First Nation: Traditional knowledge is like on-the-ground stuff. It's not a theory. From observing and testing and catching and eating, we know how the state of the resource is.
It's not that we take a piece of it and send it back east to get tested in some test tube. We put it on the table and we feed our people.
HARI SREENIVASAN: The Skagit Climate Change Consortium is combining native understanding of the ecosystem balance with their research on climate patterns. They have created models to paint a picture of how Swinomish homelands will look in the future.
So far, the model shows that 15 percent of the reservation is at risk of flooding from rising seas, including key environmental areas such as the tribes’ shellfish beds.
Biologist Larry Wasserman has worked with tribes for decades. He hopes the Skagit Consortium will be a model for policy-makers on the local level who want to prepare for climate change, but don't know how.
LARRY WASSERMAN, biologist: And, really, the issue that I believe will affect the tribes' natural resources and other folks' responses to climate is their ability to understand climate change in their backyard.
And much of the science work that's being done is being done at a regional scale or a global scale. And, so, it doesn't become usable to local communities. That's where it needs to start.
HARI SREENIVASAN: While studies show that Native people face a greater risk from shifts in the climate, Hamlet thinks they are also uniquely qualified to cope.
ALAN HAMLET: The interesting thing is that the tribes are maybe better positioned to take that long-sustainability viewpoint. We often, you know, hear about the tribes planning for seven generations ahead. That's about the right time scale for sea level rise planning.
HARI SREENIVASAN: Cladoosby believes the young people in his community are ready to tackle that long-term challenge.
BRIAN CLADOOSBY: We are slowly starting to get back one generation at a time that knowledge of treating the environment as a brother or as a sister, and that all living and non-living things live together here on this Earth.
And when you impact one, you impact the other. So we're slowly starting to see the younger generation become aware of Mother Nature.
HARI SREENIVASAN: Billy Frank says there is not really a choice.
BILLY FRANK JR.: Change, make it happen, do something, you know? And let's do it. We're running out of time, you know? So we have got to make a change.
HARI SREENIVASAN: A change for themselves and for the next seven generations.
GWEN IFILL: Preparing for that change was the subject of a conversation Hari had with members of coastal tribes from around the country at the Museum of the American Indian in Washington. We will have that tomorrow night.