CHINOOK SALMON
DID YOU KNOW?Chinook salmon may spend between 1 to 8 years in the ocean before returning
to their natal streams to spawn, though the average is 3 to 4 years.
SCIENTIFIC NAME:Oncorhynchus tshawytscha, from the Greek words onkos (hook), rynchos
(nose) Male and tshawytscha (the common name for the species in Siberia and Alaska).
COMMON NAMES: King salmon, tyee salmon, Columbia River salmon, black salmon, chub salmon, hook bill salmon, winter salmon
and blackmouth.
DESCRIPTION: The chinook salmon is blue-green on
the back and top of the head with silvery sides and white bellies; black
spots on the upper half of its body with gray/black mouth coloration. Up
to 58 inches in length and weigh up to 129 pounds; although chinook salmon
is generally up to 36 inches in length and weigh up to 30 pounds.
LIFE CYCLE: Spawning in streams that are larger
and deeper than other salmon utilize, chinook salmon spawn from late summer
to late fall, depending on the run. Fry and smolts usually stay in freshwater
from 1 to 18 months before travelling downstream to estuaries, where they
remain up to 189 days. Chinook salmon spend 1 to 8 years at sea before
returning to natal streams to spawn.
RANGE: Chinook salmon range from Kotzebue Sound,
Alaska, to Santa Barbara, California. Spawning and rearing chinook are
found in most of the rivers in this region, with significant runs in the
Columbia River, Rogue River, and Puget Sound.
HABITAT AND ECOLOGY: Freshwater streams and estuaries
provide important habitat for chinook salmon. They feed on terrestrial
and aquatic insects, amphipods, and other crustaceans while young, and
primarily on other fish when older. Eggs are laid in deeper water with
larger gravel, and need cool water and good water flow (to supply oxygen)
to survive. Mortality of chinook salmon in the early life stages is usually
high due to natural predation and human induced changes in habitat, such
as siltation, high water temperatures, low oxygen conditions, loss of stream
cover and reductions in river flow. These impacts are primarily caused
by poor forestry practices, dams, and water diversions.Estuaries and their
associated wetlands provide vital nursery areas for the chinook prior to
its departure to the open ocean. Wetlands not only help buffer the estuary
from silt and pollutants, but also provide important feeding and hiding
areas. The draining and filling of wetlands and the pollution of the estuary
from industrial discharges and run-off, negatively impact chinook salmon.
ECONOMIC VALUE: Chinook salmon is highly valued
by commercial fishermen, despite their scarcity relative to other Pacific
salmon along most of the Pacific coast. Chinook salmon is also an important
subsistence fish and a valuable recreational resource.
Revised 12/16/96
