1. Sustaining Biodiversity: The Species Approach
Chapter 9

2. Core 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
Human activities: hastening more extinctions?

3. 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.

4. Human Activities Are Destroying and Degrading Biodiversity
Human activity has disturbed at least half of the earth’s land surface
Fills in wetlands
Converts grasslands and forests to crop fields and urban areas
Degraded aquatic biodiversity

5. 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

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

7. Some Human Activities Cause Premature Extinctions; the Pace Is Speeding Up (2)
Conservative estimates of extinction = %
Growth of human population will increase this loss
Rates are higher where there are more endangered species
Tropical forests and coral reefs, wetlands and estuaries—sites of new species—being destroyed
Speciation crisis

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

9. Science Focus: Estimating Extinction Rates Is Not Easy
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 species–area relationship
Mathematical models

10. 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.

11. Species Are a Vital Part of the Earth’s Natural Capital
Instrumental value
Use value
Ecotourism: wildlife tourism
Genetic information
Nonuse value
Existence value
Aesthetic value
Bequest value
Ecological value

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

13. Are We Ethically Obligated to Prevent Premature Extinction?
Intrinsic value: existence value
Edward O. Wilson: biophilia phenomenon
Biophobia

14. 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

15. 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 overexploitation.

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

17. 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?

18. Case Study: A Disturbing Message from the Birds (1)
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

19. Case Study: A Disturbing Message from the Birds (2)
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

20. Case Study: A Disturbing Message from the Birds (3)
Greatest new threat: Climate change
Environmental indicators
Economic and ecological services

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

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

23. Case Study: The Kudzu Vine
Imported from Japan in the 1930s
“ The vine that ate the South”
Could there be benefits of kudzu?

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

25. 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

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

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

28. 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

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

30. Poaching and smuggling of animals and plants
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

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

32. 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

33. 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 aquariums.

34. 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, scientifically.

35. 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.)

36. 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

37. 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

38. Science Focus: Accomplishments of the Endangered Species Act (1)
Species listed only when serious danger of extinction
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

39. 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 organism’s survival habitat

40. 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?

41. 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

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

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

44. 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

45. The Precautionary Principle
Species: primary components of biodiversity
Preservation of species
Preservation of ecosystems