Mad Hatter My dear something seems to be troubling you Won t you tell us all about it March Hare Start at the beginning Classical Hypothesis for Pacific Salmon Evolution and Diversification Isolation during glacial advances Problem Fossil salmon pre date Pleistocene glaciations Evolution of the Pacific Salmon Pacific salmon evolved between 20 million and 6 million years ago Miocene Radiation of Pacific salmon into distinct species coincides with uplift of Pacific Rim topography Salmon and Natural Disturbances For millions of years salmon thrived in a landscape shaped by floods volcanic eruptions and natural disturbances Archaeological excavations along the Columbia River confirm extensive salmon fishing for 9300 years Butler and O Connor Quaternary Research v 62 p 18 2004 Status of Salmon Populations Today Region Alaska British Columbia Puget Sound Washington Columbia Basin Oregon California Percent of Historical Run Size 106 36 8 2 2 7 5 California Oregon Washington Idaho 5 Gresh T J Lichatowich and P Schoonmaker 2000 An estimation of historic and current levels of salmon production in the Northeast Pacific ecosystem Evidence of a nutrient deficit in the freshwater systems of the Pacific Northwest Fisheries 25 1 15 21 Will current strategies and restoration efforts work for Pacific salmon History The 5th H Strikingly similar pattern of changes to river systems and salmon crises in Great Britain New England and now the Pacific Northwest Harvest The earliest recorded salmon fishing legislation was an edict issued by King Malcolm II of Scotland in 1030 that established a closed season for taking old salmon Habitat A statute dating from the reign of Richard the Lion hearted declared that rivers must be kept free of obstructions so as to permit a well fed three year old pig standing sideways in the stream not to touch either side Hydro dams An Act passed in the reign of King Robert the First in 1318 forbade the erection of fixtures of any size or dimensions that would prevent the progress of salmon up and down a river George I Tries to Save the Salmon In 1714 George I enacted a law to prevent blocking salmon from their spawning grounds in seventeen English rivers By 1868 all seventeen rivers protected by George I were either blocked or poisoned by pollution habitat and hydro Alexander Fraser proposed steps to increase the number of salmon in Scottish rivers 1833 1 up don t block the ability of salmon to migrate or down stream hydro 2 limit fishing intensity so as to not take the majority of the spawners harvest 3 prevent habitat degradation that could damage the fishery habitat By the middle of the 19th century the plight of English salmon began to arouse widespread public concern over the danger of regional extinction The cry of Salmon in Danger is now resounding throughout the length and breadth of the land A few years a little more over population a few more tons of factory poisons a few fresh poaching devices and the salmon will be gone he will be extinct Shall we not step in between wanton destruction and so ward off the obloquy which will be attached to our age when the historians of the nineteensixties will be forced to record that The inhabitants of the last century destroyed the salmon Charles Dickens 1861 New World Salmon If the Pigeons plagued us by their abundance the Salmon gave us even more trouble So large a quantity of them enters into this river that at night one is unable to sleep so great is the noise they make in falling upon the water after having thrown or darted themselves in to the air N Denys 1672 p 199 The proliferation of small dams gradually blocked salmon from New England s rivers Between 1820 and 1880 over one hundred and fifty fishery laws relating to salmon were passed by the state of Maine Enforcement provided for at the local level was virtually nonexistant Greatworks Dam Penobscot River ey factors in British and New England salmon declines Local control lax enforcement Gradual accumulation of many individual habitat impacts Over reliance on hatcheries Is the Pacific Northwest repeating the series of choices that led to the decline of the Atlantic salmon Harvest 50 Columbia Dam Cons 40 30 20 10 0 1860 1880 1900 1920 1940 1960 1980 2000 Hydro Habitat The supply and transport of water sediment and wood interact to structure salmon habitat How well do we know what we are trying to restore Most studies of fluvial systems come from areas that no longer host frontier forests How representative is our understanding of wood in world rivers Big trees influenced big rivers Big trees were not limited to the Pacific Northwest Washington Western Red Cedar Indiana Sycamore Snags on the Missouri Karl Bodmer circa 1840 Rio Beni Bolivia Nisqually River Nisqually River Floodplain Numerous floodplain channels with inlets controlled by log jams Collins et al 2001 Army Corps of Engineers aggressively de snagged American Rivers 10000 Rivers Harbors Skagit River All Rivers 8000 6000 4000 2000 0 Collins et al 2002 1880 1900 1920 1940 1960 Snohomish River Stillaguamish River Washington Single floodplain channel with evidence of remnant side channels Collins et al 2001 Skagit 1860 Collins et al 2001 Huge losses of side channels and valley bottom wetlands along most major Puget Sound rivers yet the story for each river is unique Collins et al 2001 Reintroduction of large woody debris leads to reactivated channel avulsion Deschutes River 2001 Brummer et al in Restore Write off Rehabilitate Provide some refuge for the salmon and provide it quickly before complications arise which may make it impracticable or at least very difficult If we procrastinate and put off our rescuing mission too long it may be too late to do any good After the rivers are ruined and the salmon gone they cannot be reclaimed all the power of the United States cannot restore salmon to the rivers after the work of destruction has been completed Livingston Stone 1892 One of the few strategies that might work over the long run would be to create a network of Salmon Sanctuaries by restoring forested river corridors along river floodplains 1 Restore floodplains 2 Open blocked habitat 3 Provide adequate in stream flows 4 Hire and empower riverkeepers 5 Isolate fish farms from wild fish History Proces s
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