Sustaining Biodiversity: The Species Approach (Chapter 9- Miller & Spoolman)

Transcription

1 Sustaining Biodiversity: The Species Approach (Chapter 9- Miller & Spoolman)

2 Core Case Study: The Passenger Pigeon- Gone Forever Passenger pigeon hunted to extinction by 1900 Last wild one killed in Ohio Commercial hunters used a "stool pigeon Used to attract flocks of pigeons Archeological record shows five mass extinctions All due to natural phenomena Human activities: hastening more extinctions? Causing premature extinctions that would not happen naturally if we were not here

3 Passenger Pigeon

4 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.

5 Human Activities Are Destroying and Degrading Biodiversity Human activity has disturbed at least half of the earth s land surface (terrestrial) Fills in wetlands (Everglades is an example) Converts grasslands and forests to crop fields and urban areas Degrading aquatic biodiversity is also occurring (will discuss later)

6 Extinctions Are Natural but Sometimes They Increase Sharply Background extinction and Extinction rate % per year Mass extinction: causes? 50-95% species became extinct in the Earth s estimated 5 mass extinctions 1. End Ordovician (~445 Ma); ~12% of families, ~ 65% species; large glaciation/sea level fall?? 2. Late Devonian (~365 Ma); ~ 14% of families, ~ 72% species; impact (Siljan Crater)? 3. End Permian (~250 Ma); ~ 52 % families, >90% species; impact (Bedout Crater)?; flood basalts (Siberia); one continent; global warming; low oxygen conditions 4. End Triassic (~210 Ma); ~ 12% families, ~ 65% species; impact (Manicouagan Crater); flood basalts (Central Atlantic) 5. End Cretaceous (65 Ma); ~11% families, ~ 62% species; impact (Chixculub Crater); flood basalts (Deccan, India)

7 Levels of Species Extinction Local extinction No longer found in one area, but still somewhere else in world Ecological extinction Few individuals of species exist, but no longer play a biological role in the community Biological extinction Species is no longer found anywhere on Earth FOREVER

8 Some Human Activities Cause Premature Extinctions; the Pace Is Speeding Up Premature extinctions due to Habitat destruction Overhunting

9 Some Human Activities Cause Premature Extinctions; the Pace Is Speeding Up Conservative estimates of extinction = % Growth of human population will increase this loss Rates are higher where there are more endangered species ( hotspots ) Tropical forests and coral reefs, wetlands and estuaries sites of new species being destroyed Speciation crisis Reducing rate of speciation, limits long term recovery of biodiversity

10 Animal Species Prematurely Extinct Due to Human Activities

11 Effects of a 0.1% Extinction Rate

12 Endangered and Threatened Species Are Ecological Smoke Alarms Endangered species The classification provided to an animal or plant in danger of extinction within the foreseeable future throughout all or a significant portion of its range. Threatened species, vulnerable species The classification provided to an animal or plant likely to become endangered within the foreseeable future throughout all or a significant portion of its range.

13 Endangered Natural Capital: Species Threatened with Premature Extinction

14 Characteristics of Species That Are Prone to Ecological and Biological Extinction

15 Percentage of Various Species Threatened with Premature Extinction

16 Science Focus: Estimating Extinction Rates Is Not Easy Three problems Hard to document due to length of time Only 1.7 (to 1.8) million species identified Little known about nature and ecological roles of species identified Document little changes in DNA Estimates that species survive 1-10 million years Use species area relationship Used to estimate extinctions in shrinking habitats Mathematical models

17 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.

18 Species Are a Vital Part of the Earth s Natural Capital Instrumental value (usefulness to us) Use value Ecotourism: wildlife tourism $950 k $1.8 million/minute Genetic information: used in genetic engineering Nonuse value Existence value Aesthetic value Bequest value Ecological value Energy flow, nutrient cycling, and population control

19 Natural Capital: Nature s Pharmacy

20 Possible prostate cancer cure? What Saw Palmetto Is Used For Mainly for urinary symptoms associated with an enlarged prostate gland (also called benign prostatic hyperplasia, or BPH). Also used for other conditions, including chronic pelvic pain, bladder disorders, decreased sex drive, hair loss, hormone imbalances, and prostate cancer. Saw Palmetto Serenoa repens

21 Natural Capital Degradation: Endangered Orangutans in a Tropical Forest

22 Endangered Scarlet Macaw is a Source of Beauty and Pleasure

23 Science Focus: Using DNA to Reduce Illegal Killing of Elephants for Their Ivory 1989 international treaty against poaching elephants Currently ~400,000 wild elephants Poaching on the rise Track area of poaching through DNA analysis of elephants Analyze DNA of seized illegal ivory Elephants damaging areas of South Africa: Should they be culled? (killed to control population)

24 African elephant Loxodonta africana

25 Are We Ethically Obligated to Prevent Premature Extinction? Intrinsic value: existence value Inherent right to exist Edward O. Wilson: biophilia phenomenon Love of life Genetic kinship with nature Biophobia Fear of other forms of wildlife

26 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

27 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.

28 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

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30 Fig. 9-11a, p. 194

31 Fig. 9-11b, p. 194

32 Fig. 9-11c, p. 194

33 Fig. 9-11d, p. 194

34 Science Focus: Studying the Effects of Forest Fragmentation on Old-Growth Trees Tropical Biologist Bill Laurance, et al. Fragmentation: building roads, crop plantations, settlements, and cattle grazing areas How large must a forest fragment be in order to prevent the loss of rare trees? Within 100 m (330 ft) of fragmented edge 36% of old-growth biomass is lost within years

35 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 70% of 10,000 bird species in decline 12% are threatened with extinction Intentional or accidental introduction of nonnative species Eat the birds **Feral cats one of largest predators of birds (their eggs), other small species of rodents and lizards

36 Case Study: A Disturbing Message from the Birds Seabirds caught and drown in fishing equipment Albatross (seabird) threatened in Pacific when attracted to catches of fish and the bait used Migrating birds fly into power lines, communication towers, and skyscrapers #1 cause in US is flying into glass windows Other threats Oil spills Pesticides (DDT and the bald eagle in western US) Herbicides Ingestion of toxic lead shotgun pellets

37 Case Study: A Disturbing Message from the Birds Greatest new threat: Climate change Environmental indicators Live in every climate and biome Respond quickly to enviro. changes in habitat Easy to track and count (Christmas Bird Count had 111 th year count this past December) Economic and ecological services Name some??

38 Distribution of Bird Species in North America and Latin America

39 The 10 Most Threatened Song Birds in the USA

40 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

41 Fig. 9-14a, p. 199

42 Fig. 9-14b, p. 199

43 Case Study: The Kudzu Vine An estimated 2 million acres of forest land in the southern US is covered with kudzu. Kudzu was promoted as a forage crop and an ornamental plant when it was introduced to the U.S. at the Philadelphia Centennial Exposition in Southern farmers were encouraged to plant kudzu for erosion control from the mid 1930 s to the mid 1950 s.

44 Case Study: The Kudzu Vine In 1953, kudzu was removed from the US Department of Agriculture s list of permissible cover plants due to its recognition as a pest species. Currently in Florida, kudzu has been documented in 14 counties and is listed as a Category I invasive species.

45 Kudzu Taking Over an Abandoned House in Mississippi, U.S.

46 Some Accidentally Introduced Species Can Also Disrupt Ecosystems Argentina fire ant: 1930s 1 st in Mobile, Alabama Arrived on ships importing coffee and lumber from South America Pesticide spraying in 1950s and 1960s worsened conditions (killed native ants and genetic resistance came about in the fire ants Burmese python 1 st in Fl everglades Imported as pets from SE Asia

47 Argentina Fire Ant Accidentally Introduced into Mobile, Alabama, U.S.

48 Burmese Python Accidentally Introduced into the FL Everglades

49 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

50 Characteristics of Invader Species and Ecosystems Vulnerable to Invading Species

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52 Other Causes of Species Extinction Population growth Overconsumption Pollution Climate change

53 Other Causes of Species Extinction Pesticides DDT: Banned in the U.S. in 1972 Bioaccumulation An increase in the concentration of a chemical in specific organs or tissues at a level higher than would normally be expected Biomagnification Increase in concentration of DDT, PCBs, and other slowly degradable, fat-soluble chemicals in organisms at successively higher trophic levels of a food chain or web

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55 Bioaccumulation and Biomagnification

56 Case Study: Where Have All the Honeybees Gone? Honeybees responsible for 80% of insectpollinated plants 1/3 of human diet from insect pollinated plans Currently 30% drop in honeybee population since 1980s Dying due to? Pesticides Parasites Bee colony collapse syndrome Worker bees abandon colony and queen

57 Case Study: Polar Bears and Global Warming Environmental impact on polar bears Less summer sea ice PCBs and DDT 2007: Threatened species list Likely to decline by 30-35% by 2050

58 Polar Bear with Seal Prey

59 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 The Denver Colorado case began November 2008 and recently wrapped up in Moffat County District Court, led to the confiscation of about 25 antlers, three big game skins, a trophy elk head, 78 packages of meat, six rifles and about $22,000 in fines.

60 White Rhinoceros Killed by a Poacher

61 Individuals Matter: Jane Goodall Primatologist and anthropologist Studied chimps in Tanzania 45 years understanding and protecting chimpanzees Chimps have tool-making skills Wrote 23 books Produced 14 films about chimps

62 Individuals Matter: Dian Fossey Primatologist and zoologist from America 18 years understanding and protecting mountain gorillas in Rwanda, Africa Murdered in Rwanda 1988 Movie Gorillas in the mist

63 Rising Demand for Bush Meat Threatens Some African Species Indigenous people sustained by bush meat Meat of terrestrial wild animals used for food More hunters leading to local extinction of some wild animals Cameroon, the Central African Republic, the Congo, the Democratic Republic of the Congo, Equatorial Guinea and Gabon Animals killed in these counties are sometimes listed as threatened or endangered

64 Bush Meat: Lowland Gorilla

65 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 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.

66 9-4 How Can We Protect Wild Species from Premature Extinction? 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.

67 CITES The 1973 Convention on International Trade in Endangered Species of Wild Fauna and Flora, restricting international commerce between participating nations for plant and animal species believed to be harmed by trade. 175 countries (parties) currently involved as of

68 Convention on Biological Diversity (BCD) Focuses on ecosystems Began around 1993, with first official session of countries signed on in 1994 in the Bahamas Ratified by 190 countries (not the U.S.) It has 3 main objectives: The conservation of biological diversity The sustainable use of the components of biological diversity The fair and equitable sharing of the benefits arising out of the utilization of genetic resources

69 Case Study: The U.S. Endangered Species Act Endangered Species Act (ESA): 1973 and later amended in 1982, 1983, and 1985 FWS and NOAA federal agencies implementing ESA Identify and protect endangered species in the U.S. (through laws and management) and abroad (through trade regulation) Hot Spots Habitat Conservation Plan (HCP) colony

70 Case Study: The U.S. Endangered Species Act Mixed reviews of the ESA Weaken it Repeal it Modify it Strengthen it Simplify it Streamline it

71 Confiscated Products Made from Endangered Species

72 Science Focus: Accomplishments of the Endangered Species Act 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

73 Science Focus: Accomplishments of the Endangered Species Act Suggested changes to ESA Increase the budget Develop recovery plans more quickly Establish a core of the endangered organism s survival habitat

74 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?

75 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

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

77 Zoos and Aquariums Can Protect Some Species Limited space and funds Critics say these facilities are prisons for the organisms

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79 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

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