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Sustaining Biodiversity: The Species Approach


Sustaining Biodiversity: The Species Approach Chapter 9 * * * * * * * * * * * * * * * * * * * * * * * * * * * 9-4 How Can We Protect Wild Species from Premature ... – PowerPoint PPT presentation

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Title: Sustaining Biodiversity: The Species Approach

Sustaining Biodiversity The Species Approach
  • Chapter 9

Core Case Study The Passenger Pigeon Gone
  • Passenger pigeon hunted to extinction by 1900
  • Commercial hunters used a "stool pigeon
  • Archeological record shows five mass extinctions
  • Human activities hastening more extinctions?

9-1 What Role Do Humans Play in the Premature
Extinction of Species?
  • Concept 9-1A We are degrading and destroying
    biodiversity in many parts of the world, and
    these threats are increasing.
  • Concept 9-1B Species are becoming extinct 100 to
    1,000 times faster than they were before modern
    humans arrived on the earth (the background
    rate), and by the end of this century, the
    extinction rate is expected to be 10,000 times
    the background rate.

Human Activities Are Destroying and Degrading
  • Human activity has disturbed at least half of the
    earths land surface
  • Fills in wetlands
  • Converts grasslands and forests to crop fields
    and urban areas
  • Degraded aquatic biodiversity

Extinctions Are Natural but Sometimes They
Increase Sharply
  • Background extinction
  • Extinction rate
  • Mass extinction causes?
  • Levels of species extinction
  • Local extinction
  • Ecological extinction
  • Biological extinction

Some Human Activities Cause Premature
Extinctions the Pace Is Speeding Up (1)
  • Premature extinctions due to
  • Habitat destruction
  • Overhunting

Some Human Activities Cause Premature
Extinctions the Pace Is Speeding Up (2)
  • Conservative estimates of extinction 0.01-1.0
  • Growth of human population will increase this
  • Rates are higher where there are more endangered
  • Tropical forests and coral reefs, wetlands and
    estuariessites of new speciesbeing destroyed
  • Speciation crisis

Endangered and Threatened Species Are Ecological
Smoke Alarms
  • Endangered species
  • Threatened species, vulnerable species
  • Characteristics of such species

Science Focus Estimating Extinction Rates Is Not
  • Three problems
  • Hard to document due to length of time
  • Only 1.8 million species identified
  • Little known about nature and ecological roles of
    species identified
  • Document little changes in DNA
  • Use speciesarea relationship
  • Mathematical models

9-2 Why Should We Care about Preventing Premature
Species Extinction?
  • Concept 9-2 We should prevent the premature
    extinction of wild species because of the
    economic and ecological services they provide and
    because they have a right to exist regardless of
    their usefulness to us.

Species Are a Vital Part of the Earths Natural
  • Instrumental value
  • Use value
  • Ecotourism wildlife tourism
  • Genetic information
  • Nonuse value
  • Existence value
  • Aesthetic value
  • Bequest value
  • Ecological value

Science Focus Using DNA to Reduce Illegal
Killing of Elephants for Their Ivory
  • 1989 international treaty against poaching
  • Poaching on the rise
  • Track area of poaching through DNA analysis of
  • Elephants damaging areas of South Africa Should
    they be culled?

Are We Ethically Obligated to Prevent Premature
  • Intrinsic value existence value
  • Edward O. Wilson biophilia phenomenon
  • Biophobia

Science Focus Why Should We Care about Bats?
  • Vulnerable to extinction
  • Slow to reproduce
  • Human destruction of habitats
  • Important ecological roles
  • Feed on crop-damaging nocturnal insects
  • Pollen-eaters
  • Fruit-eaters
  • Unwarranted fears of bats

9-3 How do Humans Accelerate Species Extinction?
  • Concept 9-3 The greatest threats to any species
    are (in order) loss or degradation of its
    habitat, harmful invasive species, human
    population growth, pollution, climate change, and

Loss of Habitat Is the Single Greatest Threat to
Species Remember HIPPCO
  • Habitat destruction, degradation, and
  • Invasive (nonnative) species
  • Population and resource use growth
  • Pollution
  • Climate change
  • Overexploitation

Science Focus Studying the Effects of Forest
Fragmentation on Old-Growth Trees
  • Tropical Biologist Bill Laurance, et al.
  • How large must a forest fragment be in order to
    prevent the loss of rare trees?

Case Study A Disturbing Message from the Birds
  • Habitat loss and fragmentation of the birds
    breeding habitats
  • Forests cleared for farms, lumber plantations,
    roads, and development
  • Intentional or accidental introduction of
    nonnative species
  • Eat the birds

Case Study A Disturbing Message from the Birds
  • Seabirds caught and drown in fishing equipment
  • Migrating birds fly into power lines,
    communication towers, and skyscrapers
  • Other threats
  • Oil spills
  • Pesticides
  • Herbicides
  • Ingestion of toxic lead shotgun pellets

Case Study A Disturbing Message from the Birds
  • Greatest new threat Climate change
  • Environmental indicators
  • Economic and ecological services

Science Focus Vultures, Wild Dogs, and Rabies
Unexpected Scientific Connections
  • Vultures poisoned from diclofenac in cow
  • More wild dogs eating the cow carcasses
  • More rabies spreading to people

Some Deliberately Introduced Species Can Disrupt
  • Most species introductions are beneficial
  • Food
  • Shelter
  • Medicine
  • Aesthetic enjoyment
  • Nonnative species may have no natural
  • Predators
  • Competitors
  • Parasites
  • Pathogens

Case Study The Kudzu Vine
  • Imported from Japan in the 1930s
  • The vine that ate the South
  • Could there be benefits of kudzu?

Some Accidentally Introduced Species Can Also
Disrupt Ecosystems
  • Argentina fire ant 1930s
  • Pesticide spraying in 1950s and 1960s worsened
  • Burmese python

Prevention Is the Best Way to Reduce Threats from
Invasive Species
  • Prevent them from becoming established
  • Learn the characteristics of the species
  • Set up research programs
  • Try to find natural ways to control them

Other Causes of Species Extinction (1)
  • Population growth
  • Overconsumption
  • Pollution
  • Climate change

Other Causes of Species Extinction (2)
  • Pesticides
  • DDT Banned in the U.S. in 1972
  • Bioaccumulation
  • Biomagnification

Case Study Where Have All the Honeybees Gone?
  • Honeybees responsible for 80 of
    insect-pollinated plants
  • Dying due to?
  • Pesticides
  • Parasites
  • Bee colony collapse syndrome

Case Study Polar Bears and Global Warming
  • Environmental impact on polar bears
  • Less summer sea ice
  • PCBs and DDT
  • 2007 Threatened species list

Illegal Killing, Capturing, and Selling of Wild
Species Threatens Biodiversity
  • Poaching and smuggling of animals and plants
  • Animal parts
  • Pets
  • Plants for landscaping and enjoyment
  • Prevention research and education

Individuals Matter Jane Goodall
  • Primatologist and anthropologist
  • 45 years understanding and protecting chimpanzees
  • Chimps have tool-making skills

Rising Demand for Bush Meat Threatens Some
African Species
  • Indigenous people sustained by bush meat
  • More hunters leading to local extinction of some
    wild animals

9-4 How Can We Protect Wild Species from
Premature Extinction? (1)
  • Concept 9-4A We can use existing environmental
    laws and treaties and work to enact new laws
    designed to prevent species extinction and
    protect overall biodiversity.
  • Concept 9-4B We can help to prevent species
    extinction by creating and maintaining wildlife
    refuges, gene banks, botanical gardens, zoos, and

9-4 How Can We Protect Wild Species from
Premature Extinction? (2)
  • Concept 9-4C According to the precautionary
    principle, we should take measures to prevent or
    reduce harm to the environment and to human
    health, even if some of the cause-and-effect
    relationships have not been fully established,

International Treaties Help to Protect Species
  • 1975 Convention on International Trade in
    Endangered Species (CITES)
  • Signed by 172 countries
  • Convention on Biological Diversity (BCD)
  • Focuses on ecosystems
  • Ratified by 190 countries (not the U.S.)

Case Study The U.S. Endangered Species Act (1)
  • Endangered Species Act (ESA) 1973 and later
    amended in 1982, 1983, and 1985
  • Identify and protect endangered species in the
    U.S. and abroad
  • Hot Spots
  • Habitat Conservation Plan (HCP) colony

Case Study The U.S. Endangered Species Act (2)
  • Mixed reviews of the ESA
  • Weaken it
  • Repeal it
  • Modify it
  • Strengthen it
  • Simplify it
  • Streamline it

Science Focus Accomplishments of the Endangered
Species Act (1)
  • Species listed only when serious danger of
  • Takes decades for most species to become
    endangered or extinct
  • More than half of the species listed are stable
    or improving
  • Budget has been small

Science Focus Accomplishments of the Endangered
Species Act (2)
  • Suggested changes to ESA
  • Increase the budget
  • Develop recovery plans more quickly
  • Establish a core of the endangered organisms
    survival habitat

We Can Establish Wildlife Refuges and Other
Protected Areas
  • 1903 Theodore Roosevelt
  • Wildlife refuges
  • Most are wetland sanctuaries
  • More needed for endangered plants
  • Could abandoned military lands be used for
    wildlife habitats?

Gene Banks, Botanical Gardens, and Wildlife Farms
Can Help Protect Species
  • Gene or seed banks
  • Preserve genetic material of endangered plants
  • Botanical gardens and arboreta
  • Living plants
  • Farms to raise organisms for commercial sale

Zoos and Aquariums Can Protect Some Species (1)
  • Techniques for preserving endangered terrestrial
  • Egg pulling
  • Captive breeding
  • Artificial insemination
  • Embryo transfer
  • Use of incubators
  • Cross-fostering

Zoos and Aquariums Can Protect Some Species (2)
  • Limited space and funds
  • Critics say these facilities are prisons for the

Case Study Trying to Save the California Condor
  • Largest North American bird
  • Nearly extinct
  • Birds captured and breed in captivity
  • By 2007, 135 released into the wild
  • Threatened by lead poisoning

The Precautionary Principle
  • Species primary components of biodiversity
  • Preservation of species
  • Preservation of ecosystems