PowerPoint Presentation

							Sustaining Biodiversity:
The Species Approach

       Chapter 9
Case Study: The Passenger Pigeon:
Gone Forever

 Passenger pigeon hunted to extinction by 1900

 Commercial hunters used a "stool pigeon”

 Archeological record shows five mass
  extinctions caused by _____________

 Human activities: hastening more extinctions? Is
  this the beginning of the 6th mass extinction?
Key Concept 1: What Role Do Humans Play
in the Premature Extinction of Species?
  We are degrading and destroying biodiversity in
   many parts of the world, and these threats are
   increasing.

  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 Biodiversity

 Human activity has disturbed at least half (may
  be as much as ___%) of the earth’s land surface
  by
  • Filling in wetlands
  • Converting grasslands and forests to crop fields
    and urban areas


 and… degraded _______ biodiversity
Extinctions Are Natural but Sometimes
They Increase Sharply
 Background extinction
  • A natural biological process
  • Species are replaced over time
 Extinction rate
   Rate before humans .0001%/year = 1 extinction per
    _________ species per year
 Mass extinction: 50-___% of species, causes?

 Levels of species extinction
  • Local extinction
  • Ecological extinction
  • Biological extinction
 Some Human Activities Cause Premature
 Extinctions; the Pace Is Speeding Up
 Premature extinctions due to
  • Habitat destruction, overhunting, _____________, etc.
 Conservative estimates of current rates of extinction
  = 0.01% to 1.0%
  • Growth of human population will increase this loss
  • Estimates of at least ___% of current species extinct
    by 2050
  • Rates are higher where there are more endangered
    species
  • Tropical forests and coral reefs, wetlands and
    estuaries—sites of new species—being destroyed
     • Creating a ___________ crisis
   Animal Species Prematurely Extinct Due
   to Human Activities




 Great Auk – hunted for meat, feathers used for _____
 Dodo – habitat destruction, animals brought with sailors
  destroyed ______
 Golden Toad (recent) – believed to be a combination of climate
  change, habitat loss, disease, UV radiation, pollution
 Aepyornis – hunted, eggs eaten by _______
  Estimating Extinction Rates Is Not Easy
1. Hard to document due to long span of time to extinction
2. Only 1.8 million species identified (How many are there?)
3. Little known about nature and ecological roles of species
   identified

 Various approaches:
    Document small changes in ____
    Use species–area relationship
      • A 90% loss of habitat results in % loss of species living in
        that habitat
    Mathematical models
  Endangered Natural Capital: Species
  Threatened with Premature Extinction

Ecological Smoke
Signals:

    Endangered
    species

    Threatened
    species
    (__________
    species)

    Approx. 30,000
Characteristics of
Species That Are
Prone to Ecological
and Biological
Extinction

“The big, the slow,
the tasty, and those
with valuable parts
such as tusks and
skins.” E.O. Wilson
Key Concept 2: Why Should We Care about
Preventing Premature Species Extinction?

  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 Earth’s
Natural Capital
 Instrumental value
  • Use value – economic/ecological goods and
    services
     • Ecotourism: wildlife tourism
        • Example: 1 male lion generates $515,000 in
          tourism dollars vs. $_______ if killed for its skin
     • Genetic information
  • Nonuse value
     • Existence value (intrinsic value) – biophilia?
     • __________ value
     • Bequest value
 Ecological value
Science Focus:
Why Should We Care about Bats?
 Vulnerable to extinction
  • Slow to reproduce, human destruction of habitats


 Important ecological roles
  • Feed on crop-__________ nocturnal insects
  • Pollen-eaters
  • Fruit-eaters


 Unwarranted fears of bats
  • More people have been killed by a ________ falling
    on their head than bats
Key Concept 3: How do Humans
Accelerate Species Extinction?

 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 overexploitation.

                  **KNOW THIS**
Loss of Habitat Is the Single Greatest
Threat to Species: HIPPCO

 Habitat destruction, degradation, and
  fragmentation
    • Habitat island?
   Invasive (nonnative) species
   Population and resource use growth
   Pollution
   Climate change
   Overexploitation
   Case Study: A Disturbing Message
   from the Birds
 70% of world’s 10,000 species declining
 Habitat loss and fragmentation of the birds’ ________ habitats
   • Forests cleared - farms, lumber plant., roads, & development
 Intentional or accidental introduction of nonnative species
   • _____ 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 _____
     shotgun pellets
 Greatest new threat: _______________
 Environmental indicators
Some Deliberately Introduced Species
Can Disrupt Ecosystems
 Most species introductions are beneficial – corn,
  wheat, rice, cattle, poultry, etc.
  •   Food
  •   Shelter
  •   __________
  •   Aesthetic enjoyment

 Nonnative species may have no natural
  •   Predators
  •   Competitors
  •   Parasites
  •   _________
African Land Snail
 Imported in Brazil as a cheap substitute for
  escargot
 Grows to the size of a ___________
 When export prices for escargot fell:
  • Snails dumped into the wild
  • Spread to 23 Brazilian states
  • Devours everything from lettuce to mouse
    _________
  • Can carry lungworm – burrows into human brain
    and causes meningitis
  • Carries another parasite that can rupture the
    __________
Case Study: The Kudzu Vine

 Imported from Japan in the 1930s to control soil
  erosion, which it does
 Extremely prolific
  • “ The vine that ate the South”
 Used in Japan in food and herbal remedies
 Almost every part of plant is edible
 Japan built a processing plant in ________

 Could there be benefits of kudzu?
  • Fiber for paper, can reduce desire for ________
Some Accidentally Introduced Species
Can Also Disrupt Ecosystems
 Argentina fire ant: 1930s
  • Wiped out ___% of native ant populations
  • Killed deer fawn, birds, livestock, pets, humans
  • Pesticide spraying in 1950s and 1960s worsened
    conditions – reduced native species of ants,
    promoted genetic __________ to pesticides


 Burmese python (Everglades) – 30,000?
  • Live 25 years, grow to 20 feet, ____ pounds
  • Razor sharp teeth, squeeze prey to death,
    swallow whole – raccoons, birds, deer, etc.
  • Slowing spreading throughout southern U.S.
Characteristics of Invader Species and
Ecosystems Vulnerable to Invading Species
The Other Causes of Species Extinction

 Population growth

 Overconsumption (overexploitation)

 Pollution
  • DDT
  • Bioaccumulation
  • Biomagnification


 Climate change
Bioaccumulation and Biomagnification
Case Study: Where Have All the
Honeybees Gone?
 Honeybees responsible for ___% of insect-
  pollinated plants
  • >___ commercially grown crops. 1/3 of human diet


 Dying due to?
  • Pesticides
  • ___________
  • Bee colony collapse syndrome
     • For an unknown reason worker bees vanish from
       the hive
  • Can lead to “agricultural collapse disorder”
Illegal Killing, Capturing, and Selling of
Wild Species Threatens Biodiversity

 Poaching and smuggling of animals and plants
  • Animal parts
  • _____
  • Plants for landscaping and enjoyment


 Value to a poacher:
  •   Live mountain gorilla $________
  •   Giant Panda pelt $100,000
  •   Chimpanzee $50,000
  •   Rhinoceros horn $25,000/lb.
Rising Demand for Bush Meat Threatens
Some African Species

 Indigenous people sustained by bush meat
  • Gorilla, orangutan, chimpanzee, elephant,
    ____________


 More hunters leading to local extinction of some
  wild animals
  • Miss Waldron’s red colobus monkey
  • Reduces _____ of forest carnivores – crowned
    eagle, leopard
   Key Concept 4: How Can We Protect Wild
   Species from Premature Extinction?
 We can use existing environmental laws and treaties and
  work to enact new laws designed to prevent species
  extinction and protect overall biodiversity.

 We can help to prevent species extinction by creating and
  maintaining wildlife refuges, gene banks, botanical
  gardens, zoos, and aquariums.

 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, scientifically.
International Treaties Help to
Protect Species
 1975: Convention on International Trade in
  Endangered Species (CITES)
  • Signed by 172 countries
  • Bans hunting, capturing, and selling of threatened
    or endangered species
  • Small fees for violators
 Convention on Biological Diversity (BCD)
  • Focuses on ___________
  • Commitment to reversing the global decline of
    biodiversity
  • Ratified by 190 countries (not _______)
  • Implementation slow; No severe penalties
   The U.S. Endangered Species Act
 Endangered Species Act (ESA) 1973 - amended in 1982, 1983,
  and 1985
 1973-2007: list increased from ___ to 1,350 species (55%
  plants, 45% animals),
 Identify and protect endangered species in the U.S. and
  abroad, develop recovery plan
   • Successes: American alligator, gray wolf, peregrine falcon,
     bald eagle
 Protection includes hotspots, controlled import/export ports,
  large fines for offenses, etc.
 Habitat Conservation Plan (HCP) - Incentive for private
  landowners: allowed to ________ some critical habitat in
  exchange for taking steps to protect members of an
  ___________ species on their land
The U.S. Endangered Species Act
 Mixed reviews of the ESA
  • Puts rights and welfare of plants and animals
    above people, not been effective, caused severe
    economic losses, etc.
  • Only ___ species have been removed from list
  • Should we….?
     •   Weaken it
     •   Repeal it
     •   Modify it
     •   Strengthen it
     •   Simplify it
     •   Streamline it
 Accomplishments of the Endangered
 Species Act
 Not a failure because:
  • Species listed only when serious danger of extinction
  • Takes ________ for most species to become
    endangered or extinct
  • More than half of the species listed are stable or
    improving
  • Budget has been ______
 Suggested changes to ESA
  • Increase the budget
  • Develop recovery plans more quickly
  • Establish a core of the endangered organism’s
    survival habitat as ________
We Can Establish Wildlife Refuges
and Other Protected Areas

 1903: Theodore Roosevelt established first
  wildlife refuge

 Wildlife refuges
  • Most are _______ sanctuaries
  • More needed for endangered plants
  • Allow abandoned _______ lands to be used for
    wildlife habitats
Gene Banks, Botanical Gardens, and
Wildlife Farms Can Help Protect Species

 Gene or ______ banks
  • Preserve genetic material of endangered plants


 Botanical gardens and arboreta
  • _______ plants


 Farms to raise organisms for commercial sale
 Zoos and Aquariums Can Protect
 Some Species
 Techniques for preserving endangered terrestrial
  species
   • Egg pulling – collect in wild, hatch in zoo
   • Captive breeding – captured with aim to release
   • Artificial insemination
   • Embryo transfer – _______ mothers
   • Use of incubators
   • Cross-fostering – raised by parents of similar species
 Limited space and ______
 Critics say these facilities are prisons for the organisms,
  don’t see conservation, research benefits
Case Study: Trying to Save the
California Condor

 Largest North American bird

 Nearly extinct
  • Birds captured and breed in captivity


 By 2007, ____ released into the wild
  • Now threatened by lead poisoning from
    ammunition in animal carcasses left by ________