Sustaining Biodiversity: The Species Approach

1. Sustaining Biodiversity:The Species Approach Chapter 9

2. Core Case Study: Declining BirdSpecies (1) • Decline of 70% of 9,775 known species • Birds around humans benefited, but forest species declined • Long-distance migrants – greatest decline

3. Core Case Study: Declining BirdSpecies (2) • Reasons • Climate change • Habitat loss • Fragmentation • Birds environmental indicators • Perform economic and ecological services

4. Threatened U.S. Songbirds

5. 9-1 What Role Do Humans Play in the Premature Extinction of Species? • Concept 9-1 The current rate of species extinction is at least 100 times the rate that existed before modern humans arrived on earth, and is expected to increase to between 1,000 and 10,000 times the earlier rate during this century.

6. Three Types of Extinction • Local extinction • Ecological extinction • Biological extinction

7. Ecological Smoke Alarms • Endangered species • Threatened species • The first to go large, slow, tasty, or have valuable parts • Some behaviors make species prone to extinction

8. Species Prematurely Extinct

9. Calculating Extinction Rates • Extinction takes a long time, difficult to document • Only identified 1.8 million species – most unknown • Know little of ecological role of most species • Average species survive 1–10 million years • Species-area relationship

10. Endangered or Threatened Species (1)

11. Endangered or Threatened Species (2)

12. California Condor - Gymnogyps californianus RECOVERY • Opposed by farmers who maintained misconception • Opposed by those who felt birds had a right to freedom • Captive breeding in San Diego and Los Angeles after all 22 wild birds caught (’87) • Most expensive program ever • Released birds killed by lead and power lines • Captives trained to avoid lines • Ridley-Tree Condor Preservation Act requires non-lead bullets in range • As of April 2009, 322 individuals including 172 wild Largest North American bird, largest wingspan • Heavy bird Vulture => scavenger Live to 50yrs, sexually mature at 6 • Lay only one egg at a time, every other year • Top of food chain • Causes of endangerment: • Poaching (farmers incorrectly assumed they had killed their livestock, museums) • Lead poisoning (eating lead shot in carcasses) • DDT poisoning • Habitat destruction (gold mining)

13. Human Activities and Extinction • Background extinction rate • Current rate is 100 times background extinction • Rate likely to rise 1,000–10,000 times with climate change • Is a mass extinction coming?

14. Characteristics of Species Proneto Extinction

15. Percentage of Various Taxa Endangered

16. Current Extinction Rate Estimates Are Conservative • Species and biodiversity decrease in next 50–100 years • Biodiversity hotspot rates higher than global average • Degrading, simplifying, and destroying diverse environments

17. 9-2 Why Should We Care about Preventing 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.

18. Value of Species • Instrumental value of biodiversity • Food crops • Genetic information • Medicine • Do not know what we lose when species go extinct

19. Nature’s Pharmacy

20. Values of Species Diversity • Recreational pleasure value • Eco-tourism >$500 billion per year • Ethical obligations – intrinsic (existence) value • Foundation of earth’s ecosystems bacteria and other microorganisms

21. 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.

22. Underlying and Direct Causesof Depletion Fig. 9-7, p. 183

23. Secondary Causes of Endangerment and Premature Extinction (HIPPCO) • Habitat destruction • Invasive species • Population growth • Pollution • Climate change • Overexploitation

24. Habitat Loss • Deforestation of tropical areas greatest eliminator of species • Endemic species • Habitat fragmentation

25. Range Reductions in Four Species

26. Species Introductions • Most beneficial – food crops, livestock, pest control • 500,000 alien invader species globally • 50,000 nonnative species in the U.S.

27. Deliberately Introduced Species

28. Accidentally Introduced Species

29. Case Study: The Kudzu Vine • Kudzu introduced to control erosion • Prolific growth • Uses • Asians use powdered starch in beverages • Source of tree-free paper • Japanese kudzu farm in Alabama

30. Invasive Kudzu Vine Fig. 9-10, p. 186

31. Disruptions from AccidentallyIntroduced Species • Downside of global trade • Argentina fire ant • Burmese python

32. Argentina Fire Ant Fig. 9-11, p. 186

33. Prevention of Nonnative Species (1) • Identify characteristics of successful invaders • Detect and monitor invasions • Inspect imported goods • Identify harmful invasive species and ban transfer

34. Prevention of Nonnative Species (2) • ships discharge ballast waters at sea • introduce natural control organisms of invaders

35. Characteristics of Successful Invaders Fig. 9-12, p. 187

36. What Can You Do? Fig. 9-13, p. 188

37. Human Choices Drive Extinction • Human population growth • Excessive, wasteful consumption • Use of pesticides

38. DDT and Bioaccumulation • 1950s–1960s fish-eating bird populations drop • DDT biologically magnified in food webs • Bird’s eggshells thin and fragile • Leads to unsuccessful reproduction

39. Bioaccumulation of DDT Fig. 9-14, p. 188

40. Recovery • Bald eagle recovered • Factors leading to recovery • Ban on DDT • Crackdown on hunting • Prevention of habitat destruction

41. Climate Change and Extinction • More rapid compared to the past • Expected to eliminate >25% of land animal and plant species • Polar bears and penguins threatened

42. Illegal Killing and Trading of Wildlife • Poaching endangers many larger animals, rare plants • Over two-thirds die in transit • Illegal trade $6–$10 billion per year • Wild species depleted by pet trade • Exotic plants often illegally gathered

43. White Rhinoceros Poached for Its Horn Fig. 9-15, p. 189

44. The Value of Wild Rare Species • Declining populations increase black market values • Rare species valuable in the wild – eco-tourism • Some ex-poachers turn to eco-tourism

45. Rising Demand for Bush Meat • Traditional use of bush meat • Demand increasing with population growth • Increased road access • Loggers, miners, ranchers add to pressure • Local and biological extinctions

46. Bush Meat on the Rise Fig. 9-16, p. 190

47. 9-4 How Can We Protect Wild Species from Premature Extinction? • Concept 9-4A We can use existing environmental laws and treaties and work to enact new laws designed to prevent species extinction and to protect overall biodiversity. • Concept 9-4B We can help prevent species extinction by creating and maintaining wildlife refuges, gene banks, botanical gardens, zoos, and aquariums.

48. International Treaties • Convention on International Trade of Endangered Species (CITES) • Convention on Biological Diversity (CBD)

49. Case Study: Controversy over the U.S. Endangered Species Act (1) • National Marine Fisheries Services – ocean species • U.S. Fish and Wildlife Service – other species • Listings based on biological factors • Forbids federal agency projects that jeopardize listed species or habitats

50. Case Study: Controversy over the U.S. Endangered Species Act (2) • Fines violations on private land – 90% listed species on private land • Illegal to sell or buy listed species • 1,180 species listed • USFWS and NMFS supposed to prepare recovery plan – 25% species have a plan