Transcript Slide 1
Direct and Indirect Effects of Climate Change on Washington Salmon: Ecological Adaptations and Management Strategies Pete Bisson USDA Forest Service PNW Research Station Washington Climate Change Impacts Assessment Conference Aquatic organisms are the most imperiled animals in North America Proportion of species at risk by plant and animal group Freshwater Mussels Crayfishes Stoneflies 43% Freshwater Fishes 37% 36% Amphibians Flowering Plants 33% Gymnosperms 24% 22% Ferns/Fern Allies Tiger Beetles 19% Butterflies/Skippers Presumed/Possibly Extinct (GX/GH ) Critically Imperiled (G1) Imperiled (G2) Vulnerable (G3) 19% Reptiles 18% Dragonflies/Damselflies 18% Mammals 16% Birds 0% 69% 51% 14% 10% 20% 30% 40% 50% 60% 70% Percent of Species Source: Precious Heritage (2000) © TNC, NatureServe Water temperature Altered hydrologic regime Indirect effects Lethal temperatures Predicted annual increase 2030 0.7-1.4oF 2060 1.3-3.2oF 2090 2.2-4.9oF Migration timing Copyright 2008 by The Nature Conservancy and World Wildlife Fund, Inc. All Rights Reserved: http://www.feow.org Incubation period Altered hydrologic regime Shrinking drainage network Projected losses of salmon and trout habitat from U.S. streams O’Neal (2002) http://www.defenders.org/resources/publications/programs_and_policy/science_and_economics/global_warming /effects_of_global_warming_on_trout_and_salmon.pdf Weather extremes Reproductive losses Direct mortality Unfavorable habitat effects Indirect/incidental consequences Increased fire frequency and severity Invasive species Montana Fish, Wildlife & Parks Montana Fish, Wildlife & Parks Competing water demands Winning strategies Losing strategies Habitat generalist Abbreviated time in fresh water High stray rate Brief temp. exposure Spring spawning Habitat specialist Extended freshwater rearing Low stray rate Extended temp. exposure Fall spawning Cutthroat trout Lower risk Chum salmon Pink salmon Fall Chinook Winter steelhead Sockeye salmon Coho salmon Spring Chinook Summer steelhead Higher risk What can we do? Minimize increases in water temperature by maintaining well shaded riparian areas Maintain forests that retain snow water and promote fog drip, and lessen the “rain on snow” effect associated with large forest openings Disconnect road drainage from the stream network to soften discharge peaks during intense storms Ensure that fish have access to seasonal habitats, e.g., off-channel or cool water areas Protect springs and groundwater seeps from excessive water appropriation Thanks to: PNW Research Station Rocky Mountain Research Station NW Power and Conservation Council University of Washington