EPA's Vessel General Permit and Small Vessel General

Cowlitz Trout Hatchery winter-run population and the Clackamas River population but neither
was listed as threatened
Sexually immature summer steelhead return to the Columbia River from May to November and
spend several months in fresh water prior to spawning. When winter steelhead enter fresh water
from November to April, they are close to sexual maturity and spawn shortly after arrival in their
natal streams. Where both races spawn in the same stream, summer steelhead tend to spawn at
higher elevations than the winter forms (see Good et al., 2005).
Status and Trends
NMFS listed Lower Columbia River steelhead as threatened on March 19, 1998 (63 FR 13347),
and reaffirmed their status as threatened on January 5, 2006 (71 FR 834). The 1998 status
review noted that this ESU is characterized by populations at low abundance relative to historical
levels, significant population declines since the mid-1980s, and widespread occurrence of
hatchery fish in naturally spawning steelhead populations. During this review NMFS was unable
to identify any natural populations that would be considered at low risk.
All populations declined between 1980 and 2000, with sharp declines beginning in 1995. Those
with adequate data for modeling are estimated to have a high extinction risk (Good et al. 2005).
Abundance trends are generally negative, showing that most populations are in decline, although
some populations, particularly summer run, have shown higher return in the last 2 to 3 years
(Good et al. 2005). Historical counts in some of the larger tributaries (Cowlitz, Kalama and
Sandy Rivers) suggest the population probably exceeded 20,000 fish while in the 1990s fish
abundance dropped to 1,000 to 2,000. Recent abundance estimates of natural-origin spawners
range from completely extirpated for some populations above impassable barriers to over 700 for
the Kalama and Sandy winter-run populations (Good et al. 2005). A number of the populations
have a substantial fraction of hatchery-origin spawners in spawning areas, and are hypothesized
to be sustained largely by hatchery production. Exceptions are the Kalama, the Toutle, and East
Fork Lewis winter-run populations (Good et al. 2005).
Critical Habitat
NMFS designated critical habitat for Lower Columbia River steelhead on September 2, 2005 (70
FR 52630). Designated critical habitat includes the following subbasins: Middle
Columbia/Hood subbasin, Lower Columbia/Sandy subbasin, Lewis subbasin, Lower
Columbia/Clatskanie subbasin, Upper Cowlitz subbasin, Cowlitz subbasin, Clackamas subbasin,
Lower Willamette subbasin and the Lower Columbia River corridor. These areas are important
for the species’ overall conservation by protecting quality growth, reproduction, and feeding.
The critical habitat designation for this DPS identifies primary constituent elements that include
sites necessary to support one or more steelhead 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 quality and quantity, natural cover, forage, adequate passage conditions, and floodplain
connectivity. The critical habitat designation (70 FR 52630) contains additional description of
the watersheds that are included as part of this designation, and any areas specifically excluded
from the designation.
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