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as a recent development posing significant risk. There were no time-series data for the
CCC steelhead DPS. A variety of evidence suggested the ESU’s largest run (the Russian
River winter steelhead run) has been, and continues to be, reduced in size. Concern was
also expressed about populations in the southern part of the DPS’s range—notably those
in Santa Cruz County and the South Bay area (Good, Waples et al. 2005).
Critical Habitat
Critical habitat was designated for the CCC steelhead DPS on September 2, 2005 (70 FR
52488), and includes areas within the following hydrologic units: Russian River,
Bodega, Marin Coastal, San Mateo, Bay Bridges, Santa Clara, San Pablo, Big Basin.
Refer to the final rule for a more detailed description of critical habitat, including a map
for each hydrologic unit.
California Central Valley Steelhead
Distribution
California CV steelhead occupy the Sacramento and San Joaquin Rivers and its
tributaries (Figure 25).
Life History
California CV steelhead are considered winter steelhead by the CDFG, although “three
distinct runs,” including summer steelhead, may have occurred there as recently as
1947(CDFG 1995; McEwan and Jackson 1996). Steelhead within this DPS have the
longest freshwater migration of any population of winter steelhead. There is essentially a
single continuous run of steelhead in the upper Sacramento River. River entry ranges
from July through May, with peaks in September and February. Spawning begins in late
December and can extend into April (McEwan and Jackson 1996).
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