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Table 6. CC Chinook salmon--preliminary population structure, abundances, and hatchery
contributions (Good, Waples et al. 2005).
Population
Historical
Abundance
Most Recent
Spawner
Abundance
Hatchery
Abundance
Contributions
Eel River
(includes * tributaries below)
17,000-55,000 156-2,730 ~30%
Mainstem Eel River* 13,000 Inc. in Eel River Unknown
Van Duzen River* 2,500 Inc. in Eel River Unknown
Middle Fork Eel River* 13,000 Inc. in Eel River Unknown
South Fork Eel River* 27,000 Inc. in Eel River Unknown
North Fork Eel River* Unknown Inc. in Eel River Unknown
Upper Eel River* Unknown Inc. in Eel River Unknown
Redwood Creek 1,000-5,000 Unknown 0
Mad River 1,000-5,000 19-103 Unknown
Bear River 100 Unknown 0
Mattole River 1,000-5,000 Unknown Unknown
Russian River 50-500 200,000 ~0%
Humbolt Bay tributaries 40 120 40 (33%)
Tenmile to Gualala coastal effluents Unknown Unknown 0
Small Humboldt County rivers 1,500 Unknown 0
Rivers north of Mattole River 600 Unknown 0
Noyo River 50 Unknown 0
Total 20,750-72,550 200,175 (min)
Status and Trends
CC Chinook salmon were listed as threatened on September 16, 1999 (64 FR 50393).
Their classification was reaffirmed following a status review on June 28, 2005 (70 FR
37160). The outcome was based on the combined effect of dams that prevent individuals
from reaching spawning habitat, logging, agricultural activities, urbanization, and water
withdrawals in the river drainages that support CC Chinook salmon. Historical estimates
of escapement, based on professional opinion and evaluation of habitat conditions,
suggest abundance was roughly 73,000 in the early 1960s with the majority of fish
spawning in the Eel River [see CDFG 1965 in (Good, Waples et al. 2005)]. The species
exists as small populations with highly variable cohort sizes and discussion is underway
to split Eel River salmon into as many as five separate populations (see Table 3). The
Russian River probably contains some natural production. However, the origin of those
fish is unclear as a number of introductions of hatchery fish occurred over the last
century. The Eel River contains a substantial fraction of the remaining Chinook salmon
spawning habitat for this species.
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