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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
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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 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 exchange-generating 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)
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: 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
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