Our new Biological Assessment is out - Klamath Basin Crisis

Part 3 COHO SALMON
Information about the coho salmon for this BA may be found in this section,
including species description, environmental baseline, and effects of the Proposed
Action.
Coho Salmon Species Description and
Distribution
Species Description
Coho salmon (Oncorhynchus kisutch)
have an anadromous life history in
which juveniles are born and rear in
freshwater, migrate to the ocean, where
they grow to maturity, and adults return
to fresh water to spawn. They spawn
only once and then die (referred to as
semelparity).
In the Klamath River, the majority of the
returning spawning coho salmon are three
years old. Some precocious males known
as "jacks" return as two-year-old
spawners. Juveniles typically rear in
freshwater for one full year and then
migrate to the sea in the spring after
their first winter of life.
Adult Female Coho Salmon – Ocean Stage
Adult Male Coho Salmon – Spawning Stage
Distribution
Coho salmon are a widespread species of Pacific salmon, occurring in most major
river basins around the Pacific Rim from Monterey Bay in California north to
Point Hope, Alaska; through the Aleutians; and from the Anadyr River in Russia
south to Korea and northern Hokkaido, Japan (Laufle et al. 1986).
Within the Klamath River Basin, coho salmon may be found throughout the
drainage below Iron Gate Dam (IGD). IGD is owned and operated by PacifiCorp
and is currently a barrier to anadromous salmonid migrations in the main stem
Klamath River. Klamath Project facilities are located upstream of IGD.
Table 3-1 shows the approximate river mile for select locations that will be a
useful reference for this BA.