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Conservation Chapter 14 Wildlife Resources What is happening to the wildlife and plant resources around us today? U.S. Species Diversity Decreasing Biodiversity 10-20% of species alive in 1975 were extinct in 2000 Mostly plants, invertebrates in tropical rain forests (many undescribed species) 40% of all species live in tropical areas Disappear along with forests Extinction Not New 99% of all species have gone extinct Gradual environmental changes have been responsible for most extinctions Rapid environmental changes from asteroids, etc. also have been important in many extinctions Extinction Rates Background (natural) rate of extinction Mass extinction Why Should We Care About Extinctions and Biodiversity? 1) economics 2) aesthetics 3) ecological 4) ethics Cinchona Cinchona ledogeriana, South America Quinine for malaria treatment Rauvolfia Rauvolfia sepentina, Southeast Asia Tranquilizer, high blood pressure medication Foxglove Digitalis purpurea, Europe Digitalis for heart failure Pacific yew Taxus brevifolia, Pacific Northwest Ovarian cancer Human Impacts on Biodiversity Human Impacts on Biodiversity Flathead Lake, Montana Causes of Premature Extinction of Wild Species Human Activities That May Cause Extinctions Habitat disturbance/destruction Commercial hunting Predator and pest control Collecting for pets, zoos, research Pollution Introductions of exotic species Habitat Disturbance and Destruction California Condor Commercial Hunting Black Rhino Range in 1700 Range today (about 2,400 left) Predator and Pest Control African Elephant Probable range 1600 Range today (300,000 left) Collecting for Pets, Zoos, Research Pollution Bald Eagle - DDT Species Introductions Dodo Bird Zebra Mussel Threats from Nonnative Species Strategies for Protecting Biodiversity Species approach Ecosystem approach Protecting Wild Species: The Legal Approach International Treaties: CITES - Convention on International Trade in Endangered Species National Laws: ESA - Endangered Species Act Protecting Wild Species: The Sanctuary Approach Wildlife refuges and protected areas - e.g. whooping cranes Gene banks, botanical gardens, and farms Zoos and Aquariums - captive breeding programs The Ecosystem Approach Biosphere reserves U.S. has >30 reserves - Yellowstone National Park - Great Smoky Mtns. National Park Other countries have similar reserves The Ecosystem Approach Bird Success Stories California Condor Whooping Crane Peregrine Falcon Canada Goose Wild Turkey