EPA's Vessel General Permit and Small Vessel General

high rating of conservation value for the species. In addition, the Columbia River
rearing/migration corridor downstream of the spawning range was rated as a high conservation
value. Limiting factors identified for the Upper Columbia River steelhead include: mainstem
Columbia River hydropower system mortality, reduced tributary stream flow, tributary riparian
degradation and loss of in-river wood, altered tributary floodplain and channel morphology, and
excessive fine sediment and degraded tributary water quality.
Final Protective Regulations
NMFS proposed in June 2004 to list Upper Columbia River steelhead as threatened (69 FR
33102). As part of the proposed listing determination NMFS proposed applying the amended
4(d) protective regulations to Upper Columbia River steelhead. On January 5, 2006, NMFS
issued a final determination listing the Upper Columbia River steelhead Distinct Population
Segment (DPS) as threatened, and announced that it would finalize the protective regulations in a
subsequent Federal Register notice (71 FR 834). In the final rule NMFS applied the 4(d)
protective regulations, as amended in June 2005, to the Upper Columbia River steelhead DPS
(71 FR 5178). These regulations are described in the Protective Regulations for Threatened
Salmonid Species section of this document. These protections apply to natural and hatchery fish
with an intact adipose fin, but not to listed hatchery fish that have had their adipose fin removed
prior to release into the wild.
Upper Willamette River Steelhead
Distribution and Description of the Listed Species
The Upper Willamette River steelhead DPS includes all naturally spawned populations of
winter-run steelhead in the Willamette River, Oregon, and its tributaries upstream from
Willamette Falls to the Calapooia River (inclusive). No artificially propagated populations that
reside within the historical geographic range of this DPS are included in this listing. Hatchery
summer-run steelhead occur in the Willamette Basin but are an out-of-basin population that is
not included in this DPS.
The native (late) winter-run steelhead, with spring Chinook salmon, are the only two populations
of salmon believed to historically occur above Willametter Falls. The construction of a fish
ladder at the falls in the late 1880s, allowed for the passage of summer steelhead from Skamania
Creek and winter-run steelhead from Big Creek (i.e., Gnat Creek). The two groups of winter-run
steelhead exhibit different return times. The later run exhibits the historical phenotype adapted
to passing the seasonal barrier that existed at Willamette Falls prior to construction of the fish
ladder. The early run of winter-run steelhead are considered non-native, and were derived from
Columbia River steelhead outside the Willamette River (Good et al. 2005). While the release of
these hatchery winter-run fish was recently discontinued, some fish from earlier releases now
reproduce naturally within the upper Willamette River Basin. Nonnative summer-run hatchery
steelhead continue to be released within the upper basin (Good et al. 2005).
Native steelhead in the Upper Willamette are a late-migrating winter group that enters fresh
water in January and February (Howell et al. 1985a). They do not ascend to their spawning areas
until late March or April (Dimick and Merryfield 1945) and spawning occurs from April to June.
125