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Carbaryl, Carbofuran, and Methomyl - National Marine Fisheries ...

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Table 19. LCR Steelhead salmon populations, abundances, <strong>and</strong> hatchery contributions<br />

(Good, Waples et al. 2005).<br />

Population<br />

Historical<br />

Abundance<br />

Most Recent<br />

Spawner<br />

Abundance<br />

Hatchery<br />

Abundance<br />

Contributions<br />

Cispus River Unknown Unknown Unknown<br />

Tilton River Unknown 2,787 ~73%<br />

Upper Cowlitz River Unknown Unknown Unknown<br />

Lower Cowlitz River 1,672 Unknown Unknown<br />

Coweeman River 2,243 466 ~50%<br />

South Fork Toutle River 2,627 504 ~2%<br />

North Fork Toutle River 3,770 196 0%<br />

Kalama River-winter run 554 726 0%<br />

Kalama River-summer run 3,165 474 ~32%<br />

North Fork Lewis River-winter run 713 Unknown Unknown<br />

North Fork Lewis River-summer run Unknown Unknown Unknown<br />

East Fork Lewis River-winter run 3,131 Unknown Unknown<br />

East Fork Lewis River-summer run 422 434 ~25%<br />

Salmon Creek Unknown Unknown Unknown<br />

Washougal River-winter run 2,497 323 0%<br />

Washougal River-summer run 1,419 264 ~8%<br />

Clackamas River Unknown 560 41%<br />

S<strong>and</strong>y River Unknown 977 42%<br />

Lower Columbia gorge tributaries 793 Unknown Unknown<br />

Upper Columbia gorge tributaries 243 Unknown Unknown<br />

Hood River-winter run Unknown 756 ~52%<br />

Hood River-summer run Unknown 931 ~83%<br />

Wind River 2,288 472 ~5%<br />

Total 25,537 (min) 9,870 (min)<br />

Life History<br />

Summer steelhead return to freshwater from May to November, entering the Columbia<br />

River in a sexually immature condition <strong>and</strong> requiring several months in freshwater before<br />

spawning. Winter steelhead enter freshwater from November to April. They are close to<br />

sexual maturation <strong>and</strong> spawn shortly after arrival in their natal stream. Where both races<br />

spawn in the same stream, summer steelhead tend to spawn at higher elevations than the<br />

winter forms. Juveniles rear in freshwater (stream-type life history).<br />

Status <strong>and</strong> Trends<br />

LCR steelhead were listed as threatened on March 19, 1998 (63 FR 13347), <strong>and</strong><br />

reaffirmed as threatened on January 5, 2006 (71 FR 834). The 1998 status review noted<br />

that this ESU is characterized by populations at low abundance relative to historical<br />

levels, significant population declines since the mid-1980s, <strong>and</strong> widespread occurrence of<br />

154

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