saving the Pacific Salmon
Saving the Pacific Salmon
Salmon are one of the most important fish species in the world, and in the Pacific Northwest the fish are a way of life for many species of plants and animals, including humans. The major problem that humans are facing is that the population of wild salmon is dangerously low as compared to historic numbers due to over-fishing and human degradation (including dams, chemical pollution and land use impacts.). Pacific Salmon are now extinct in forty percent of the rivers they once thrived in (Four Fish). Zoologist George Suckley stated in 1854, that the Pacific coast salmon were “one of the striking wonders of the region...these fish....astonish by number, and confuse with variety.”(In a Sea of Trouble) and that “The quantities for salmon which frequent these waters is beyond calculation, and seems to be so great as to challenge human ingenuity to effect it in any way.” (In a Sea of Trouble). In order to get a better grasp on the problems humans are causing we need to first understand the salmon's life cycle.
In the Pacific Northwest there are five different species of salmon: Chinook, Pink, Dog, Coho, and Silver. All of which are anadromous basically meaning that they live in both fresh and salt water. These fish start life hatching many miles upstream on the gravel beds in rivers on the pacific coasts of North America, and Asia, were they grow into smolts as they are carried downstream to the sea. Once at sea the salmon spend one to seven years maturing. Then for reasons unknown to scientists, a homing impulse triggers them to make an astonishing journey back to the very river or tributary they were hatched in (Salmon). At least that is how it is supposed to work. When Lewis and Clark made their famous expedition nearly two centuries ago they marveled at the “great quants. of Salmon” they had seen in the Columbia River in Washington State, which in 1860 produced sixteen million salmon annually. Today the figure has dropped to less than one million respectively (Where the Salmon Rule). In 1990 not one sock-eye salmon out of a population of thousands made its way back to its spawning area in Redfish Lake, Idaho (In a Sea of Trouble).
The brutal decline is emblematic of the problem. Biologists Willa Nehlen, Jack Williams, and James Litchatowich reported that of the hundreds of distinct native populations that were once common to the Pacific Coast are disappearing. Of the original stocks 106 are extinct, 102 definitely face extinction, fifty-eight are at moderate risk, and fifty-four are a matter of concern. All in all the report said that 214 natural spawning routes are in very serious trouble (Fish-eries Mar. /April issue).
What possibly could be the reason for the sharp decline of this life giving species of fish? HUMANS.
Let’s start with dams. The first half of the twentieth century, in order to harness the power of the rivers in the Pacific Northwest for producing electricity, and producing water for irrigation in the semi-arid valleys, countless dams were built. The engineers that built these structures had the salmon in mind during the design phase. They constructed fish ladders and artificial falls designed to allow the upstream passage for the salmon past all the concrete now blocking the rivers vital to the species. On the Columbia River alone eight major dams were built, while a spattering of additional smaller dams were plugging up the tributaries.
There was something that the engineers did not account for and that is for each existing dam five to fourteen percent of adult salmon moving upstream cannot find the fish ladders, or if they do end up getting lost in the vast reservoirs created between dams. And worse yet the engineers designed the ladders and artificial falls for fish moving upstream, not the smolts making their way downstream to the Pacific Ocean. It is estimated that we lose ninety percent of the smolts that...
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