PowerPoint PresentationSlide 2Slide 3Classical Hypothesis for Pacific Salmon Evolution and DiversificationEvolution of the Pacific SalmonSalmon and Natural DisturbancesSlide 7Status of Salmon Populations TodaySlide 9Slide 10Slide 11HarvestHabitatHydro (dams)Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27How well do we know what we are trying to restore?Slide 29Slide 30Slide 31Slide 32Nisqually RiverSlide 34Army Corps of Engineers aggressively “de-snagged” American RiversSlide 36Slide 37Slide 38Slide 39Slide 40Slide 41Slide 42Slide 43Slide 44Slide 45Mad 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 DisturbancesFor 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 1-8, 2004Status of Salmon Populations TodayRegion Percent of Historical Run Size •Alaska 106•British Columbia 36 •Puget Sound 8•Washington <2•Columbia Basin <2•Oregon 7•California 5•California, Oregon, Washington, Idaho 5Gresh, 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 HStrikingly similar pattern of changes to river systems and salmon crises in Great Britain, New England, and now the Pacific Northwest.HarvestThe 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”.HabitatA 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.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] George I Tries to Save the SalmonAlexander Fraser proposed steps to increase the number of salmon in Scottish rivers (1833):(1) don’t block the ability of salmon to migrate up 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 nineteen-sixties will be forced to record that: ‘The inhabitants of the last century destroyed the salmon’…“ — Charles Dickens (1861).“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).New World SalmonThe 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 RiverLocal control / lax enforcementGradual accumulation of many individual habitat impactsOver-reliance on hatcheriesKey factors in British and New England salmon declinesIs the Pacific Northwest repeating the series of choices that led to the decline of the Atlantic salmon?HarvestHydro0102030405018601880190019201940196019802000Columbia RiverDam ConstructionHabitatThe 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 riversBig trees were not limited to the Pacific NorthwestWashington(Western Red Cedar)Indiana(Sycamore)Snags on the Missouri Karl Bodmer, circa 1840Rio BeniBoliviaNisqually RiverNisqually River FloodplainNumerous floodplain channels withinlets controlled by log jams Collins et al. (2001)02000400060008000100001880 1900 1920 1940 1960Rivers & HarborsSkagit RiverAll RiversArmy Corps of Engineers aggressively “de-snagged” American RiversCollins et al. (2002)Snohomish RiverStillaguamish River, WashingtonSingle floodplain channel withevidence of remnant sidechannels Collins et al. (2001)Skagit 1860Collins 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)Deschutes River2001Brummer et al. (in review) Reintroduction of large woody debris leads to reactivated channel avulsionWrite off?Restore?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
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