Biological Wealth Goods and services provided by biodiversity. ~$38 Trillion per year Examples of Goods and Services Gas, climate, and water regulation Water supply Erosion control Soil formation Pollination Biological Wealth = $38 Trillion/Year Biological control Food production Recreation Raw materials Nutrient cycling Waste treatment Two Kinds of Value Instrumental: beneficial to humans Sources for agriculture, forestry, aquaculture, and animal husbandry Recreational, aesthetic, and scientific value Sources of medicine Intrinsic: value for its own sake Source for Agriculture: Wild or Cultivated? Highly adaptable to changing environments Have numerous traits for resistance Lack genetic vigor Source for Agriculture: Wild or Cultivated? High degree of genetic diversity Represents the genetic bank Need highly controlled environmental conditions High degree of genetic diversity Need highly controlled environmental conditions Sources for Medicine: Vincristine Sources of Medicine Vincristine from rosy periwinkle cures leukemia. Capoten from the venom of the Brazilian viper controls high blood pressure. Taxol from the bark of the pacific yew used to treat ovarian, breast, and small-cell cancers. Recreational, Aesthetic, and Scientific Value Ecotourism: largest foreign exchangegenerating enterprise in many developing countries $104 billion spent on wildlife-related recreation $31 billion spent to observe, feed, or photograph wildlife Intrinsic Value Value for Their Own Sake. Why? Philosophical/Moral issue. Not a scientific issue. Saving Wild Species Game animals in the United States Acts protecting endangered species Past Wildlife Management Problems Restoring the numbers of many game animals, e.g., deer, elk, turkey Passing laws to control the collection and commercial exploitation of wildlife Poaching and over hunting Contemporary Wildlife Management Problems Road-killed animals Population explosion of urban wildlife Lack of natural predators Wildlife as vectors for certain diseases Pet predation by coyotes Changed societal attitudes towards animals Acts Protecting Endangered Species Lacey Act: forbids interstate commerce of illegally killed wildlife Endangered Species Act (ESA): protects endangered and threatened species Species at Risk: United States Total endangered U.S. species = 987 (388 animals, 599 plants) Threatened U.S. species = 276 (129 animals, 147 plants) The Status of U.S. Species Causes of Animal Extinctions Reasons for Biodiversity Decline Habitat alterations Conversions Fragmentation Simplification Reasons for Biodiversity Decline Pollution Examples Acid Rain Caused by combustion of fossil fuels 10% of lakes in eastern US affected DDT DDT used to kill insect pests Biological amplification causes high levels in secondary and tertiary consumers Causes fragile shells in predatory birds Decline in Bald Eagle, Osprey, Peregrine Falcon etc… Reasons for Biodiversity Decline Introduction of exotic species, e.g., Starling, House Sparrow, Oriental Bittersweet, Multiflora Rose etc… Reasons for Biodiversity Decline: Human Population Growth Reasons for Biodiversity Decline: Overuse Examples Harvest of 50 million songbirds for food – Southern Europe Trafficking in wildlife and products derived from wild species – $10 billion/year 90% decline in rhinos 1.6 tons of tiger bones = 340 tigers Parrot smuggling: 40 of 330 species face extinction What steps should we take to reduce biodiversity decline? Birds of Prey Bald Eagle Considered threatened by 1921 Extinct in North East by 1937 First use of DDT – 1943 to kill lice in Europe and in US army Extensive use in nature started ~1955, peaked in 1962 Biological Amplification DDT is fat soluble Cannot be flushed out of body Accumulates in tissues Organisms high on the food chain most effected