EPA's Vessel General Permit and Small Vessel General

Lower Columbia River Chinook Salmon
Distribution and Description of the Listed Species
The Lower Columbia River Chinook salmon ESU includes all naturally spawned populations of
Chinook salmon from the Columbia River and its tributaries from its mouth at the Pacific Ocean
upstream to a transitional point between Washington and Oregon, east of the Hood River and the
White Salmon River, and includes the Willamette River to Willamette Falls, Oregon, exclusive
of spring-run Chinook salmon in the Clackamas River.
Lower Columbia River Chinook salmon have three life history types, including early fall runs
(tules), late fall runs (brights), and spring-runs. Spring and fall runs have been designated as part
of a Lower Columbia River Chinook salmon ESU. The Cowlitz, Kalama, Lewis, White Salmon
and Klickitat Rivers are the major river systems on the Washington side, and the lower
Willamette and Sandy Rivers are foremost on the Oregon side. The eastern boundary for this
species occurs at Celilo Falls, which corresponds to the edge of the drier Columbia Basin
Ecosystem and historically may have been a barrier to salmon migration at certain times of the
year. Fall Chinook salmon typically enter the Columbia River in August through October to
spawn in the mainstem of the large rivers (Kostow 1995). Spring Chinook salmon enter
freshwater in March through June to spawn in upstream tributaries and generally emigrate from
fresh water as yearlings.
Status and Trends
NMFS originally listed Lower Columbia River Chinook salmon as threatened on March 24, 1999
(64 FR 14308); NMFS reaffirmed the threatened status of Lower Columbia River Chinook
salmon on June 28, 2005 (70 FR 37160). Historical records of Chinook salmon abundance are
sparse, but cannery records suggest a peak run of 4.6 million fish (43 million pounds) in 1883
(Lichatowich 1999). Although fall-run Chinook salmon are still present throughout much of
their historical range, they are still subject to introgression by large-scale hatchery production,
relatively high harvest, and extensive habitat degradation. The Lewis River late-fall-run
Chinook salmon population is the healthiest and has a reasonable probability of being selfsustaining.
Abundances largely declined during 1998 to 2000 and trend indicators for most
populations are negative, especially if hatchery fish are assumed to have a reproductive success
equivalent to that of natural-origin fish (Good et al. 2005). Most populations for which data are
available have a long-term declining population trend (Good et al. 2005).
Critical Habitat
NMFS designated critical habitat for Lower Columbia River Chinook salmon on September 2,
2005 (70 FR 52630). Designated critical habitat includes all Columbia River estuarine areas and
river reaches proceeding upstream to the confluence with the Hood Rivers as well as specific
stream reaches in a number of tributary subbasins. These areas are important for the species’
overall conservation by protecting quality growth, reproduction, and feeding. The critical habitat
designation for this ESU identifies primary constituent elements that include sites necessary to
support one or more Chinook salmon life stages. Specific sites include freshwater spawning
sites, freshwater rearing sites, freshwater migration corridors, nearshore marine habitat and
estuarine areas. The physical or biological features that characterize these sites include water
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