How to See Pacific Salmon Make Their Epic Annual Migration

Every year, millions of salmon return from the Pacific Ocean to their natal rivers and streams in one of North America's most remarkable wildlife events: the salmon run.

Against the deep green of the Pacific Northwest forest, flashes of silver, pink, and red fill the rushing river as salmon battle their way upstream. People travel from around the world to see the extraordinary sight of Pacific salmon making nests and reproducing before dying. 

In August, Chinook salmon are expected to pass the Ballard Locks fish ladder in Seattle. If you’re in Alaska, chum salmon are expected to swim through Williwaw Creek while pink salmon migrate through Prince William Sound—just to name a few locations that you can spot these fish on their epic journey. 

Here’s everything you need to know about the Pacific Northwest salmon run, why it’s important and where you can glimpse this natural marvel. 

What Are Salmon Runs?

This phenomenon is not just one momentous event. Multiple species of salmon head upstream across vast areas from late spring to winter. “There's no such thing as ‘the salmon run,’” says Thomas Quinn, emeritus professor at University of Washington.

North America has five species of Pacific salmon “that go to sea, come back, spawn, and die,” he says. Here, these species—Chinook (king), coho, sockeye, chum, and pink salmon—have a habitat range that extends “from California all the way up to Alaska through British Columbia.” 

They are born in freshwater and migrate to the ocean during the smolting phase of their life cycle. During this transition, the young salmon experience physical changes to their bodies that allow them to survive in saltwater. Their gills transform to secrete salt rather than absorbing it—if this didn’t happen, they would dehydrate and die when reaching the ocean.

Food is the main reason the salmon go to sea, says Quinn. In their freshwater breeding grounds “there's not much to eat.”

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After one to seven years—depending on the species—adults return to freshwater rivers or streams to lay their eggs. 

The river's flowing freshwater not only keeps the eggs clean of silt and waste but also gives the salmon eggs more access to oxygen. As oxygen-rich water moves across the egg's permeable membrane, dissolved oxygen molecules pass directly through the shell to the developing embryo in a process called passive diffusion.

Female salmon also dig nests, known as redds, to protect their eggs. “She's trying to dig a depression in the stream bed that makes a safe place for eggs and also cleaning the gravels that her eggs will go down into,” says Nat Geo Explorer Matt Sloat, director of science at the Wild Salmon Center.”

To display their fitness, males vibrate their bodies alongside a female as if they’re dancing. Then they swim over her and repeat their shimmy on the other side. Males also fight for dominance, biting each other viciously with prominent teeth grown specially for fighting. 

“They'll break off and have this battle with another male,” says Sloat. “Then they'll come back and dance.”

The Journey That Feeds Entire Ecosystems

The annual migration supports entire ecosystems.

Adults return to the freshwater breeding grounds, bringing elements like carbon, phosphorus, and nitrogen from the ocean. When they die, these marine-derived nutrients spread across the ecosystem. 

Salmon carcasses also support the food web as they decompose in streams and feed organisms known as periphyton—“scum on rocks that are fed upon by aquatic insects,” explains Quinn. Those insects are eaten by animals further up the food chain. 

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Many species feed directly on the salmon remains, including bears, coyotes, bald eagles, crows, and river otters. This transports marine-derived nutrients onto land, fertilizing nearby trees. One study even detected these nutrients in the grapes of nearby vineyards. 

Brown and black bears play a key role in this transfer. They’re “almost like a traffic cop directing the nutrients,” says Quinn. Of all the animals feasting on salmon, strong bears are the best at moving the bodies onto land. “They're the ultimate all-terrain vehicle.”

Where to See the Pacific Northwest Salmon Run

The Klamath River is just one of many locations to see this phenomenon, with timings varying by species and location from Northern California up to Oregon, Washington, and into Alaska.

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Alaska is a hotspot for activity. “You have to go out of your way not to see salmon,” says Sloat. Brooks Falls in Katmai National Park, Russian River Falls in Kenai Peninsula, and Williwaw Creek near Anchorage are just a few world-famous destinations to see the run. 

But even smaller bodies of water can put on a good show. “Every little trickle up the B.C. and Southeast Alaska coast” will be full of spawning salmon, says Quinn. 

The runs continue through the fall. In September, Coho salmon arrive in Salmon Cascades, Washington, while Chinook salmon run in Clackamas County, Oregon.  

The next month, sockeye salmon swim into the Adams River in British Columbia. This dominant run takes place every four years due to the species’ lifecycle. The rivers run red with salmon, and the community celebrates their return with a special festival called the Salute to the Sockeye.

The spectacle even happens miles inland. “Chinook swim—and I know this is hard to believe—3,000 kilometers up the Yukon River, all the way into British Columbia,” says Quinn. “But we also have them spawning within a kilometer of saltwater here in Puget Sound.” 

Dedicated viewing platforms and guided tours —in national parks, hatcheries, fish ladders, and over rivers—are a terrific way to enjoy the run. Those unable to travel can watch the show via SalmonCam livestreams from Issaquah, Washington, and Alaska’s Brooks Falls or Crooked Creek.

Smaller streams offer more easily visible fish while bigger sites can be more dramatic. For example, at the world-famous Brooks Falls in Alaska “you see all the salmon jumping and the bears catching them in midair,” says Sloat. 

Threats to Salmon Populations 

This incredible sight could be under threat because of population declines across the Pacific Northwest. Wild salmon populations have been heavily impacted by human activities, such as pollution, overfishing, urban development, building dams, and gold mining, says Robert Lackey, professor of fisheries at Oregon State University. “In the 1850s and 1860s, widespread and expanding West Coast mining activities accelerated the decline.”

Habitat restoration projects to rebuild the population are underway. Four major dams in the Klamath River—spanning northern California and Southern Oregon—were removed after blocking the salmon’s passage for around a hundred years. “It's the largest dam removal project in the history of the world,” says Sloat. Since the last dam was removed, “10,000 Chinook moved up past where the dams were.” 

Populations that migrate further inland generally struggle more, as do those that live in freshwater for longer as juveniles because they spend more time in ecosystems affected by habitat loss. 

Restoring abundance is possible, says Lackey, “but only if society is willing to make currently unpopular but effective choices that fundamentally alter how people live.”

Protections could help people experience the wonder of these fish returning to freshwater for generations to come. Quinn is enjoying the spectacle himself: “Just a couple days ago, I was up in Southeast Alaska with my son, watching them being pounced upon by bears.”