Librería 7artes
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Librería Elías (Asturias)
Librería Kolima (Madrid)
Librería Proteo (Málaga)
Over half a million fall Chinook once spawned in the middle and upper Snake River. Today, 100 percent of that prime spawning area is behind dams that do not have fish ladders. Hells Canyon Dam, the third dam of the Hells Canyon Complex was completed in 1961. Fall Chinook numbers were estimated at 15,000 in 1957 and dwindled to less than 10 fish by 1971. On the North Fork Clearwater River in Idaho, steelhead returning from the ocean once produced 1,000 redds (nests) per mile. The North Fork is approximately 28 percent of the Clearwater basin, but produced 50 to 60 percent of the entire Clearwater basin’s steelhead production. The North Fork of the Clearwater River was also suitable spawning habitat to accommodate 74,000 Chinook salmon redds. Today, the North Fork of the Clearwater River is unavailable to steelhead and Chinook. Dworshak Dam, built without a fish passage system was completed in 1968. In order to have healthy, harvestable, self-sustaining salmon populations, there must be an adequate number of returning adults reaching an adequate volume of spawning habitat. If the number of returning adults is diminished, or the volume of adequate habitat is diminished, healthy, harvestable, self-sustaining salmon populations cannot be maintained. Recent studies and research have been limited in the scope of their efforts, limiting possible outcomes. Some are agenda driven while others ignore basic salmon biology. It is the purpose of this effort to present timeline 'cause and effect', to help develop the needed focus to save Snake River Salmon.
