Chinook SalmonOncorhynchus tshawytschaWhere and when to see them

Chinook salmon, also called king salmon, are the largest Pacific salmon. Native to the North Pacific and its rivers, they are a defining species of the Columbia River basin. Most hatch in freshwater, grow at sea, and return to freshwater to reproduce. Their migrations support food webs, fisheries, and the cultures and livelihoods of Indigenous peoples throughout the region. Despite their global conservation status, many Columbia basin populations face serious pressures from altered habitat, dams, warming water, and other threats.

Size

Adults commonly measure 60–100 cm in length; exceptionally large fish can reach about 150 cm.

Weight

Adults commonly weigh 5–20 kg; exceptional individuals can exceed 45 kg.

Lifespan

Usually 3–7 years, although some mature earlier or live longer.

Status

Least Concern globally; some Columbia River basin populations are federally listed as threatened or endangered.

Most Chinook salmon are anadromous, migrating between freshwater and the ocean. Young fish spend varying periods in rivers before moving downstream and adapting to saltwater. Adults generally return to their natal river system, using environmental cues and their sense of smell to locate spawning areas. Columbia River Chinook are commonly grouped into spring, summer, and fall runs according to when adults enter the river. River entry and spawning may be separated by several months. A female digs a gravel nest, called a redd, with sweeping movements of her tail, while males compete for access to spawning females. Adults stop feeding during their freshwater spawning migration and rely on stored energy. Both sexes die after spawning, returning nutrients to river and stream ecosystems.

• Chinook are the largest of the Pacific salmon.
• Some early-maturing males are known as jacks.
• Their sense of smell helps them find their home river.
• Spawning adults carry ocean-derived nutrients into freshwater ecosystems.

Wildlife opportunities depend on the river reach, water levels and species. River-specific viewing months have not been confirmed; general species seasons are not a local sighting forecast.

Chinook salmon use freshwater rivers, estuaries, and the North Pacific Ocean during their life cycle. In the Columbia basin, spawning habitat includes suitable gravel beds in the main river and its tributaries. Eggs need flowing, oxygen-rich water moving through the gravel to develop successfully. Juveniles use river margins, side channels, and estuarine habitats for feeding and shelter, with habitat use differing among populations. Dams, passage barriers, sediment, and high water temperatures can reduce habitat quality or limit access to spawning grounds.

Young Chinook in freshwater eat aquatic insects, small crustaceans, and other small animals, including fish where available. In estuaries and coastal waters, they feed on planktonic crustaceans and increasingly on small fish. Ocean-dwelling adults are predominantly fish predators, taking prey such as herring, anchovies, and sand lance, along with some squid and crustaceans. Returning adults generally cease feeding after entering freshwater to spawn.

Common name

Chinook Salmon

Scientific name

Oncorhynchus tshawytscha

Animal group

Fish

Size

Adults commonly measure 60–100 cm in length; exceptionally large fish can reach about 150 cm.

Weight

Adults commonly weigh 5–20 kg; exceptional individuals can exceed 45 kg.

Lifespan

Usually 3–7 years, although some mature earlier or live longer.

Status

Least Concern globally; some Columbia River basin populations are federally listed as threatened or endangered.

Identification

At sea and early in their river migration, Chinook have silvery sides, a blue-green back, and small black spots on the back and both lobes of the tail. A black mouth with dark gums along the lower jaw is a useful distinguishing feature, especially compared with coho salmon, which usually have pale lower gums. Spawning fish darken and may develop olive, brown, reddish, or purplish tones, while males develop a hooked snout. Size alone is unreliable because young or early-maturing Chinook can overlap with other salmon species.