Sustaining Biodiversity: The Species Approach

1. Sustaining Biodiversity: The Species Approach G. Tyler Miller’s Living in the Environment 14th Edition Modified by Mr. Manskopf Chapter 12

2. Edward Abbey …the love of wilderness is more than a hunger for what is always beyond reach; it is also an expression of the loyalty to the earth, the earth which bore us and sustains us, the only home we shall ever know, the only paradise we ever need-if only we had eyes to see. Original sin, the true original sin, is the blind destruction for the sake of greed of this natural paradise which lies around us…

3. Chapter 12 Key Concepts • Human effects on extinction rates • Understanding biodiversity and extinction • How human activities endanger wildlife • Preventing extinction

4. How does a species go from having billions to extinct in just one century…The Passenger Pigeon Story. Extinct in the wild since 1900 and last died in the Cincinnati Zoo 1914.

5. Section 1 Key Ideas What are the 3 types of extinctions? What are endangered and threatened species? How do biologists estimate the number of extinctions? How are humans impacting extinction rates?

6. Species Extinction • Local extinction:species no longer found in a Specific location. • Ecological extinction: when so few are located they no longer play a role in a ecosystem. • Biological extinction: when species no longer exists anywhere. GONE FOREVER!

7. Endangered and Threatened Species • Endangered species: has so few individuals it may soon be extinct. • Threatened (vulnerable) species:declining numbers mean it may soon become endangered. Certain characteristics make some species more vulnerable…big, slow, tasty or have valuable parts (ie. Tusks) Northern spotted owl (threatened) Florida manatee Gray wolf Florida panther Bannerman's turaco (Africa)

8. TNC estimates 1/3rd of 21,000 identified U.S. animal and plant species are vulnerable. 30,000 of the world’s species and 1,200 in U.S. are officially endangered.

10. Characteristics that make a species prone to extinction.

11. Percent of various types of species endangered.

12. How do biologists estimate extinctions • 99.9% of all species that ever existed are extinct. • Extinctions are “normal” • What is happening for last few centuries not “normal”… mass extinction.

13. Extinction Rates • Background (natural) rate of extinction • Extinction spasm • Massextinction Fig. 5-9 p. 96

15. How do biologists estimate extinctions • Hard to figure out (extinctions take long time…) • ID only 1.4-1.8 million of 5-100 million species Truth: we don’t know how many species are becoming extinct. SPECIES AREA = 90% loss of habitat = 50% loss of species

16. Problems Estimating Extinction Rates Extinction not easily documented over time Many species remain unidentified Little is known about most identified species

17. Estimating Extinction Rates: Look up for homework page 228 Species-area relationships Population viability analysis (PVA) Minimum viable population (MVP) Minimum dynamic area (MDA)

18. How are humans affecting extinction rates? Biologists estimate that current extinction rate is 1,000 to 10,000 times the rate before humans. Before humans one species per million per year (0.0001%) TODAY: 0.1 to 1% Between 5,000 and 100,000 per year depending upon how many

19. How are humans affecting extinction rates? 0.1% to 1% seen as conservative estimate: • Likely to increase due to population and footprint • “Hot Spots” under attack • Simplifying ,many ecosystems… monoculture Estimates 20% of world’s plants and animals gone by 2030 and 50% by end of century

20. How are humans affecting extinction rates? • Habitat fragmentation and disturbance leads to more opportunistic species like weeds, cockroaches, rodents etc. • Numbers based on limited data • Precautionary Principle “To keep every cog and wheel is the first precaution of inelegant tinkering.”

22. Section 2 Key Ideas • Why should we preserve wild species? • What is the intrinsic value of a species?

23. Importance of Wild Species Why should we care if species go extinct??? Won’t other species evolve and take their place??? Main Answer: it would likely to at least 5 million years for evolution to rebuild the biodiversity we are likely to destroy this century… what about spiritual answer?

24. Importance of Wild Species Instrumental Value: based upon the usefulness of species (economic and ecological) • Food crops • Fuels • Paper • Medicines • Genetic Information • Recreation (eco tourism)

25. Importance of Wild Species Why care about bats??? • 950 known species • Reproduce slowly • Live in huge colonies • Feed on insects that may be harmful • Distribute seeds or pollinate trees • Keystone Species Unwarranted fear 10 people in 4 decades in U.S.

26. Intrinsic Value of Species Some people believe that each wild species has an inherent right to exist and play its ecological role no matter its usefulness. • Biophilia • Does that mean all species??? • What do you think?

27. Importance of Wild Species Rebuilding biodiversity is slow Instrumental value Genetic information Eco-tourism Ecological value Intrinsic value (biophilia)

29. Section 3 Key Ideas • What is the role of habitat loss and degradation in species extinction? • What is the role of habitat fragmentation? • How are birds impacted?

32. Causes of Depletion of Wild Species • Human population growth • Increasing per capita resource use • Endangered centers of biodiversity • Environmental destruction • Spread of opportunistic species

33. Causes of Premature Extinction of Wild Species Fig. 12-6 p. 231

34. Habitat Loss and Degradation Greatest threat to species “HIPPO” Habitat destruction Invasive species Population (humans) growth Pollution Overharvesting

35. Species squeezed into smaller and more fragmented habitat

36. Habitat Fragmentation Species are more vulnerable to extinction when their habitats are divided into smaller and more isolated patches. • Harder to reproduce • More vulnerable to predators • Vulnerable to diseases • Vulnerable to catastrophic events (fires, etc.) • Difficulty finding food, shelter etc.

42. Bird Extinctions • 70% of world’s 9,800 known bird species are declining • 1/6 endangered • Habitat loss and fragmentation • Nonnative species (cats eating birds, rats and snakes) • Pet trade (parrots)

43. Bird Extinctions • Hooked on fishing lines • Collide with powerlines, skyscrapers, wind turbines • Oil spills • Pesticides • Swallow lead from bullets

44. Bird Extinctions Environmental indicators: because they live in every climate and biome, are easy to track and respond to changes quickly Important: • Pollination • Control pests • Spread seeds

46. Section 4 Key Ideas What is the role of deliberately introduced species? What is the role of accidentally introduced species? How can the threat of nonnative species be reduced? Deer population case study

47. Nonnative Species Deliberately Introduced We depend upon nonnative species for: • Economic systems • Food • Shelter • Medicine • Aesthetics Corn, wheat, rice, livestock, etc. (98% of food supply in U.S.)

48. Nonnative Species Deliberately Introduced PROBLEM: When compete, control or destroy native species. • Throws off ecosystem balance • 50,000 nonnative species in U.S. • Compete for resources • No predators

49. Nonnative Species Deliberately Introduced Nonnative (Invasive) species 2nd leading cause of extinctions 95% in Hawaii Cats kill estimated 568 million birds in U.S. per year Animals and Plants

50. Deliberately introduced species Accidentally Introduced Species Page 235