How shrinking snowpack is hurting salmon in the Pacific Northwest

How shrinking snowpack is hurting salmon in the Pacific Northwest

Sisters, ore.

Bob Reese has been leading salmon fishing trips in Oregon for nearly 30 years. When he first started as a professional Fishing guide In 1996, life was good. He was doing a job he loved, and fish were plentiful.

But things have changed in Oregon’s rivers over the decades.

“We’re closed to wild fish, wild salmon, wild Chinook salmon, wild trout,” Reese said. “Historically, we’ve had about 200 days of meaningful opportunities. Today we’re down to about 50 people.

The decline of salmon and steelhead has a number of reasons. Hydroelectric dams have left them isolated from their habitat and changed river flows. The hatchery fish has caused problems with genetics. We have been overfished on some trips.

But there is one key indicator that Reese looks to when he tries to gauge the upcoming season.

“We are watching with great concern the amount of snow accumulating in the Cascade Mountains,” he said.

Snowpack in the Pacific Northwest has been shrinking for years, especially at lower elevations, and that trend is expected to continue as climate change continues to push temperatures higher.

Under a “business as usual” scenario, where greenhouse emissions remain unchecked, snowpack in the Pacific Northwest is expected to decline by 60% by 2050. According to For the latest climate assessment in Oregon.

Related: Washington’s snowpack is on track to decline by nearly half by the 2080s

Credit: Bulletin

A small amount of snow remains on the Cascades as a car drives along the Cascade Lakes Highway on Friday, July 30, 2021. Ryan Brennick / The Bulletin

Snow typically acts as a frozen reservoir, releasing its water during the warm summer months, feeding the rivers and streams that salmon depend on to survive.

Even with all the other problems facing salmon, Reese said the Pacific Northwest’s dwindling snowpack stands out.

“The only thing that will save this species is year after year of high snowpack, high flows and cold water that sends those events downstream in a rapid manner,” he said.

Warmer winter, smaller snowpack

At the Deer Creek trailhead near Santiam Pass in the central Oregon Cascades, snow falls close to Chris Jordan’s legs. He is unaffected.

“This is it,” he said. “We have less than a foot of snow accumulation here at 4,000 feet in February. That’s a fifth of what it should be.”

Jordan is a fish biologist at the National Oceanic and Atmospheric Administration, or NOAA. He has been studying the relationship between salmon and ice for decades. He explained that when it comes to snow, looks can be deceiving.

“Over 6,000 feet, it’s a normal snow year,” he said, noting that it was snow at lower elevations that showed the most alarming decline. “The snow level in the Cascades Pass, which ranges from 4,000 to 6,000 feet, has decreased over the past decade.”

This is largely due to rising temperatures caused by greenhouse gas emissions and climate change, Jordan said.

The amount of precipitation in the Pacific Northwest has not decreased, but as temperatures rise, more of it is falling as rain rather than snow.

“This is the line where rain versus snow moves uphill, and if it moves up too far, it moves beyond where the mountains can catch it,” he said.

While snowpack has taken the biggest hit in recent years, some aspects of the region’s winter landscape have been declining for longer than that.

Glaciers show long-term trends

Snowpacks can be highly variable from season to season, but glaciers in the Pacific Northwest provide a comprehensive view of snowpacks over the years.

Glaciers form when more snow falls on an area than it melts in the summer. Every year, a new layer forms, compressing the layer underneath, eventually forming solid ice.

Andrew Fountain, a professor of geology and geography at Portland State University, has been fascinated by ice since he was a child.

“When I was in middle school, I used to collect snowflakes,” he said. “I was one of those kids who really loved the ice.”

The fountain saw glaciers in the mountains of the Northwest and showed the effects of climate change.

“Glaciers are actually a tangible indicator of what’s happening to our snowpack. “If we have a lot of snow in the winter, we’ll have bigger glaciers,” he said. “The long-term trend we know from measurements, we actually only know by observing “Glaciers, is that every year our snowpack is shrinking, getting thinner, melting a little bit faster.”

The Pacific Northwest is home to the most glaciers in the United States outside of Alaska, Fountain said, including seven on Mount Hood alone.

In 1907, those glaciers covered an area of ​​about 4.2 square miles. By 2014, those same glaciers covered only 2.4 square miles discount By 43%.

Credit: John Goodwin, KGW

Snow falls on the ground at Timberline Lodge in Government Camp, Oregon, on Friday, November 4, 2022.

This trend has been repeated on mountains throughout the Northwest, from Hood to Mount Rainier to the Olympic Peninsula, and is expected to worsen as climate change continues to raise temperatures.

“The glaciers on the Olympic Peninsula should be gone by 2070,” Fountain said. “This reflects the disappearance of snowpack as well as increased melting in the summer.”

This type of loss has serious consequences for species that depend on melting snow.

“Glaciers and snow keep the river water cold, which is really important for a number of fish species, including salmon,” Fountain said. “So, with our snowpack gone, and now with our glaciers gone, river water temperatures will rise in the summer and become less habitable for important fish species.”

“What we think about winter has changed.”

Certain species of salmon and steelhead have evolved over thousands of years, adapting to the reliable schedule of high river flows at specific times of the year.

“The timing and amount of flow in river systems fed by snowmelt is critical for spring Chinook and steelhead,” Jordan said. “This has happened over thousands of years, but this shift from a rain regime to a snow regime happens over decades, and that’s too fast for fish to keep up. Evolution doesn’t happen that fast.”

For Jordan, it’s easy to tell what kind of salmon he’ll see later in the year just by looking at the snow, or lack thereof, in the winter.

“You see the water disappear in February, when it should stay until April and even June, and you know what your summer looks like,” he said. “The survival of juvenile salmon seems to be really bad in the high desert of Oregon.”

Jordan realizes that the forecast for future snow accumulation is not great. Given how long greenhouse gases such as carbon dioxide remain in the atmosphere, even if we stopped burning fossil fuels today, temperatures would not begin to fall for many years.

“What we think about has changed with winter,” he said.

So does this mean our beloved salmon are doomed to failure? They don’t have to be, Jordan said.

Searching for hope in the floodplain

He explained that water is stored in two ways: either in snow – which Jordan called the “ice box” – and as groundwater seeping into the floodplains, which he called “the sponge.”

“We can’t change the amount of ice and we can’t change the amount stored in the ice chest, but we can change the amount stored in the sponge,” he said. “We can make more sponges. We can bring back the sponges that we have dried up and removed from the landscape.

To demonstrate how this works, Jordan demonstrated restoration work at Wychus Creek, outside Sisters.

The creek is fed by the glaciers of the Middle and North Sister, two high peaks in the central Cascades, before feeding into the Deschutes River, which in turn feeds the Columbia River before it meets the Pacific Ocean.

The restored area was donated to the Deschutes County Land Trust. Before restoration, the creek ran in one main channel, with high banks and fast-moving water. To return it to its natural state, crews worked to level the ground.

“Where the ground is higher, the lower it is,” Jordan said. “Where the ground was low, fill it up again.”

Today, this part of the creek meanders over a wide area. Instead of a main channel, water flows in and around gravel bars and logs harvested nearby. The goal of these types of restoration projects is to slow the flow of water.

Credit: Kurt Austin/KGW

A restored portion of Wychus Creek in Deschutes County slowed the flow of water and allowed more of it to be stored as groundwater.

“Instead of just flowing quickly all the way to the ocean, it has a longer residence time,” he said. “It has to be spread across the surface of the floodplain so it can absorb it, and that’s the value of this project.”

Jordan acknowledged that the creek may not look like what most people imagine when they think it is a healthy river, but he said that kind of thinking needs to change.

“This restoration project looks like it’s a mess. There’s wood everywhere, there’s water everywhere. You don’t see a beautiful canal with a grassy bank that you can walk through and picnic in,” he said. “This is a different view of what a river view looks like.” “Healthy.”

But without reliable snowpack to replenish the rivers and streams that fish depend on, creating more groundwater sponges like those at Wychus Creek may be our best shot at preserving salmon and steelhead over the long term.

It is unclear how many miles of rivers would need to be restored to compensate for the loss of snow, but Jordan said the more miles the better.

“It’s safe to say we need to do more of that,” he said. “We need to rethink what we want our rivers to look like in order to get fish and deal with the changes that are happening with climate change.”

“We don’t have a viable business model.”

The stakes couldn’t be higher for people like Bob Reese, a salmon fishing guide.

“Historically, we’re used to seeing spring Chinook on the Clackamas River back around Easter in early April,” he said. “Now a lot of the racing doesn’t come back until July and August.”

The decline in snow density and the species that depend on snowmelt has had a ripple effect on salmon fishing trips, Reese said.

“We have to find another job. There’s no full-time fishing guide here anymore,” said Reese, who had to find another boat fishing job to supplement his income. “We don’t have a viable business model anymore.”

The ripple effects extend far beyond the rivers and streams where Reese takes people fishing.

“We’re stuck with people who don’t spend their money in rural Oregon,” he said. “Fishing represents one of the greatest transfers of wealth from urban to rural communities, and these people don’t come and spend their money on the Oregon coast or in small towns like Clatscany on the Columbia River.”

Rees has witnessed restoration efforts on rivers and streams like the Wychus, and hopes they can begin to reverse the trend he has seen developing over the past three decades.

But Rees is also a realist, so his optimism remains cautious.

“Will it happen fast enough to save the salmon? We’re not sure.”

You may also like...

Leave a Reply

Your email address will not be published. Required fields are marked *