Early Closure Alert!
The Aquarium will close two hours early on Wednesday, December 24. Last entry at 3pm; exhibits close at 4pm. The Aquarium will be closed on December 25.
Salmon

From fresh to salt water and back again

Pacific salmon are anadromous, which means they’re born in freshwater, migrate to the ocean on a journey that can be hundreds of miles long, and then return to freshwater to reproduce—most often, to the same stream in which they were born. With the exception of steelhead salmon and cutthroat trout, Pacific salmon die soon after spawning.

Salmon life cycle infographic

(Click image to enlarge.)

Multiple vs. terminal spawners
The Pacific Northwest is home to seven species of salmon. Steelhead salmon and cutthroat trout have different life cycles than the others—they can spawn multiple times. Chinook, coho, chum, sockeye and pink salmon spawn only once and then die.
The name game
Each species of terminally spawning Pacific salmon has a nickname, making it seem like there are a lot more than five: chinook are also known as king; coho are also known as silver; chum are also known as dog; sockeye are also known as red; and pink are also known as humpy.
Fish with a lot of influence
Salmon are a keystone species—which means they have a disproportionately large effect on their environment relative to their abundance. In other words, even though their populations are relatively small, the health of salmon impacts the health of many other kinds of species as well.
Against all odds
Each female salmon may deposit up to 5,000 eggs, depending on species, in up to seven nests (called redds). Of those eggs, only a very few—from none to just 10—will survive to become adult salmon. And that doesn’t even take into account the likelihood that the adult salmon will complete the journey from the ocean to the river to spawn!
A perilous journey
Adult salmon face a lot of challenges as they make their way from the ocean back to freshwater. They may get caught in a fisherman’s net, or by a hungry bear, eagle or otter. They may have to swim through polluted waters near populated areas. They may have to overcome high obstacles—some manmade, like dams; others natural, like waterfalls.
How can we help salmon?
Pacific salmon populations are struggling for a variety of reasons, most of them caused by humans. There are many actions each of us can take to help ensure a healthy habitat for salmon, including conserving water and electricity at home; properly disposing of garbage, pet waste and household chemicals so they don’t run off into our waterways; participating in habitat restoration projects; and encouraging friends and family members to take action as well!

Map


Salmon range

Quick Facts

Diet: Carnivore
Average lifespan in the wild: 4–5 years
Size: Varies by species; 30”–58” long
Protection Status: Varies by stock; some endangered