9-1 What Role Do Humans Play in the Premature Extinction of Species?

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2 9-1 What Role Do Humans Play in the Premature Extinction of Species? The Natural World is everywhere disappearing before our eyes cut to pieces, mowed down, plowed under, gobbled up, replaced by human artifacts. E. Wilson Extinctions are natural but sometimes they increase sharply Background Extinction = a continuous, low level of extinction of species over time. Mass Extinction extinction of many species in a relatively short period of time. The Earth has experienced 5 Mass Extinctions according to Geologic time

3 Three Levels of Species Extinction 1. Local extinction a species is no longer found in an area it once inhabited, but is still found elsewhere. 2. Ecological extinction when so few members of a species are left that it can no longer play its ecological roles in the biological communities it lives in. 3. Biological extinction a species no longer found anywhere on earth. Irreversible

4 Above; animals that have become prematurely extinct because of humans Some human activities cause premature extinctions, and the pace is speeding up! Conservation Biologists Project that during this century the extinction rate will increase 10,000 times and amount to an annual extinction rate of 1% per year! Current Extinction Rate 0.1%

5 Endangered & Threatened Species are Ecological Smoke Alarms Endangered Species so few individual survivors that the species could soon become extinct over all or most of its natural range. Ex. Passenger Pigeon Threatened Species - still abundant in its natural range but, because of declining numbers, is likely to become endangered in the near future. vulnerable The Red Lists published by World Conservation Union; puts out annually the list that shows the world s threatened species. You can check it out online at:

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7 Percentages of various types of species threatened with premature extinction because of humans! Behavioral Characteristics that make species vulnerable to extinction!

8 9-2 Why Should We Care about Preventing Premature Species Extinction? Species are a Vital part of the Earth s Natural Capital It takes 5-10 million years for natural speciation to rebuild the biodiversity we are likely to destroy during our lifetime. Biologists say: we should act now to prevent it partly for the species Instrumental Value. their usefulness to us in providing many ecological and economic services that make up the earth s Natural Capital. Instrumental Values: Use Values benefit us in the form of economic goods and services, ecological services, recreation, science, etc. * Ecotourism - wildlife tourism that generates economic benefits. * Genetic Information - used to produce genetically modified crops and foods.

9 Nonuse Values: * Existence Values the satisfaction of knowing certain things like redwood forest exist. * Aesthetic Values - appreciation for its beauty. * Bequest Values - paying to protect some natural capital for future. Ecological Value vital components of the key ecosystem functions of energy f low, nutrient cycling, and population control. * Thus an important component of Natural Capital that supports Earth s life. Are we Ethically Obligated to Prevent Premature Extinction? Each species has: Intrinsic Value - right to survive and play its ecological role, regardless of usefulness to us! We should all have Biophilia, a love of life. But some still have Biophobia, a fear of the wildlife.

10 9-3 How do Humans Accelerate Species Extinction? Loss of Habitat is the Single Greatest Threat to Species HIPPCO Habitat Destruction, degradation, and fragmentation; Invasive species, Population and resource use growth; Pollution; Climate change; and Overexploitation. These are the most important causes of Premature Extinction!

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12 A Disturbing Message from the Birds: Approximately 70% of the world s 10,000 known bird species are declining in numbers 1 out of every 8 is threatened because of habitat loss, degradation, and fragmentation. Why are there more bird species in Latin America than North America? 10 most threatened species of U.S. Songbirds

13 Some Deliberately Introduced Species Can Disrupt Ecosystems 2 nd biggest cause of premature extinctions. introduced species * Benefit - ecosystem services, food, shelter, medicine and aesthetics. * Problem - they have no natural predators, and over populate + increase competition with native species. Example - Kudzu Vine brought over from Japan to control soil erosion. Some Accidentally Introduced Species Can Also Disrupt Ecosystems Stowaways brought over from other continents during importation & travel. Example Argentina Fire Ant accidentally introduced in Alabama.

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15 Prevention is the Best Way to Reduce Threats from Invasive Species Ways to do This: 1. Fund research to identify characteristics of successful invader species. 2. Increase ground surveys and satellite observations to detect and monitor. 3. Step up inspection of imported goods and goods carried by travelers. 4. Require cargo ships to discharge their ballast water and replace it with saltwater at sea before entering ports; or require them to sterilize the water. 5. Increase research to find and introduce natural predators, parasites, bacteria, to control invasive species.

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17 Population Growth, Overconsumption, Pollution, and Climate Change Can Cause Species Extinction. Population Growth & Overconsumption: Human population growth is excessive & wasteful to resources Pollution: Example Bioaccumulation/Magnification Honeybees: pesticides Case Study: 1/5 of colonies lost Global Warming: Polar Bears

18 Illegal Killing, Capturing, and Selling of Wild Species Threatens Biodiversity Poaching: illegally killing species for their valuable parts. White Rhinos killed for their horns; $25,000 per pound! Gorilla live = $150,000 Dead used as Bush Meat by locals. Jane Goodall: - 45 years studying Chimps. - Discovered their use of tools -Jane Goodall Institute to protect chimps. Live chimp = $50,000

19 9-4 How Can we Protect Wild Species from Extinction Resulting from our Activities? International Treaties Help Protect: 1975 Convention on International Trade in Endangered Species (CITES) * bans: hunting, capturing and selling Convention on Biological Diversity (CBD) * legally commits participating governments to reverse the global decline of biodiversity and to equitably share the benefits from the world s genetic resources; includes invasive species control. (U.S. doesn t participate!) In U.S.: The Endangered Species Act of 1973 designed to identify and protect endangered species in U.S. & abroad. Controversial, some believe it has helped but others think it has hindered economic development on private land. Still in the works! Confiscated products

20 Other ways we can help: * Wildlife refuges protected lands * Gene Banks seed banks to preserve genetic information of species. * Botanical Gardens arboretas; contain live plants. * Wildlife farms raising individuals for commercial sale. * Zoos or Aquariums Egg pulling or Captive Breeding to increase numbers. Precautionary Principle: substantial preliminary evidence indicates that an activity can harm human health or environment. Used to protect species Better safe than Sorry!