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Chapter 11 Sustaining Biodiversity: The Species Approach.

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1 Chapter 11 Sustaining Biodiversity: The Species Approach

2 Core Case Study: The Passenger Pigeon - Gone Forever  Once the most numerous bird on earth.  In 1858, Passenger Pigeon hunting became a big business. Habitat loss – forests cleared Habitat loss – forests cleared Hunters catch one pigeon & lure others Hunters catch one pigeon & lure others Feathers – pillows, bones – fertilizer, meat – food Feathers – pillows, bones – fertilizer, meat – food  By 1900 they became extinct from over-harvest and habitat loss. Females laid one egg per year Females laid one egg per year Last wild bird shot in 1900 Last wild bird shot in 1900 Figure 11-1

3 SPECIES EXTINCTION  Species can become extinct: Locally: A species population is no longer found in an area it once inhabited but is still found elsewhere in the world. Locally: A species population is no longer found in an area it once inhabited but is still found elsewhere in the world. Ecologically: Occurs when so few members of a species are left they no longer play its ecological role. Ecologically: Occurs when so few members of a species are left they no longer play its ecological role. Globally (biologically): Species is no longer found on the earth. (forever) Globally (biologically): Species is no longer found on the earth. (forever)

4 Global Extinction  Some animals have become prematurely extinct because of human activities. Figure 11-2

5 Endangered and Threatened Species: Ecological Smoke Alarms  Endangered species: so few individual survivors that it could soon become extinct.  Threatened species: still abundant in its natural range but is likely to become endangered in the near future.

6 Fig. 11-3, p. 224 The first species to go tend to be the big, the slow and the tasty ones; those whose valuable parts can be sold.

7  Some species have characteristics that make them vulnerable to ecological and biological extinction. SPECIES EXTINCTION Figure 11-4

8 SPECIES EXTINCTION

9 Biologists use measurements and models to estimate extinction rates.  Background extinction, mass extinctions, and mass depletions account for a loss of 99.9% of all species that have ever existed. Extinction spasm describes the loss of a large number of species within a few centuries. Extinction spasm describes the loss of a large number of species within a few centuries.  Predicting extinctions is always difficult because of three factors. Usually takes a long time, so is difficult to document/prove. Usually takes a long time, so is difficult to document/prove. Only a small percent of the world’s species have even been identified. Only a small percent of the world’s species have even been identified. We know very little about most of the world’s identified species. We know very little about most of the world’s identified species.

10 SPECIES EXTINCTION Various methods are used to estimate extinction rates: Study past records Study past records Current Scientific data (IUCN Redlist) Current Scientific data (IUCN Redlist) Base-line info on change in biodiversity over time Base-line info on change in biodiversity over time Species-area curves Species-area curves When 90% of an area is lost, ~50% species are extinctWhen 90% of an area is lost, ~50% species are extinct Predicting population sizes, measure habitat changes/availability and species interactions Predicting population sizes, measure habitat changes/availability and species interactions Figure 2. Global Living Planet Index, 1970-2005 The Living Planet Index measures population size of hundreds of species, to determine a global trend in biodiversity. It has declined 27 percent from 1970 to 2005. Source: WWF, 2008 WWF, 2008

11 SPECIES EXTINCTION  Scientists use measurements and models to estimate extinction rates. The International Union for the Conservation of Nature and Natural Resources (IUCN) publishes an annual Red List, listing the world’s threatened species. The International Union for the Conservation of Nature and Natural Resources (IUCN) publishes an annual Red List, listing the world’s threatened species. The 2004 Red List contains 15,589 species at risk for extinction. The 2004 Red List contains 15,589 species at risk for extinction.

12  Lower Risk (LR) was a catch-all category which includes common species as well as those for which there may be conservation concern, but which do not warrant a higher category. Category was removed, promoting its subcategories to full categories. LR/cd (Conservation Dependent) stable and sizable populations depend on sustained conservation activity. LR/cd (Conservation Dependent) stable and sizable populations depend on sustained conservation activity. NT (Near Threatened, formerly LR/nt), close to qualifying for listing as Vulnerable but not fully meeting those criteria; slowly declining or fairly small populations but probably no danger of going extinct even without conservation activity in the foreseeable future, or threats suspected to affect taxon in the near future but still avoidable. NT (Near Threatened, formerly LR/nt), close to qualifying for listing as Vulnerable but not fully meeting those criteria; slowly declining or fairly small populations but probably no danger of going extinct even without conservation activity in the foreseeable future, or threats suspected to affect taxon in the near future but still avoidable. LC (Least Concern, formally LR/lc), species that have been evaluated and found to be so common that no conservation concern is projected in the foreseeable future. LC (Least Concern, formally LR/lc), species that have been evaluated and found to be so common that no conservation concern is projected in the foreseeable future. Examples: LR/cd: Coast Redwood; LR/nt: Bigcone Douglas-fir; LR/lc: Leopard (the species as a whole), Orca, House Sparrow. Examples: LR/cd: Coast Redwood; LR/nt: Bigcone Douglas-fir; LR/lc: Leopard (the species as a whole), Orca, House Sparrow.Coast RedwoodBigcone Douglas-firLeopardOrcaHouse SparrowCoast RedwoodBigcone Douglas-firLeopardOrcaHouse Sparrow  Vulnerable (VU): faces a considerable risk of extinction in the medium term. Examples: Ring-tailed Lemur, Great White Shark, Royal Poinciana. Examples: Ring-tailed Lemur, Great White Shark, Royal Poinciana.Ring-tailed LemurGreat White SharkRoyal PoincianaRing-tailed LemurGreat White SharkRoyal Poinciana  Endangered (EN): faces a high risk of extinction in the near future. Examples: Blue Whale, Desert Bighorn Sheep, Giant Panda, Black-footed ferret Examples: Blue Whale, Desert Bighorn Sheep, Giant Panda, Black-footed ferret Blue WhaleDesert Bighorn SheepGiant PandaBlack-footed ferretBlue WhaleDesert Bighorn SheepGiant PandaBlack-footed ferret  Critically Endangered (CR): faces an extremely high risk of extinction in the immediate future. extinction Examples: Slender-billed Curlew, Spanish Lynx, Red Wolf. Examples: Slender-billed Curlew, Spanish Lynx, Red Wolf.Slender-billed CurlewSpanish LynxRed WolfSlender-billed CurlewSpanish LynxRed Wolf  Extinct in the Wild (EW): captive individuals survive, and/or the species has been reintroduced outside its former natural range, but the species otherwise matches the criteria for "Extinct", such that no free-living, natural population is believed to exist. "Extirpated" is a term used for localized extinctions of extant species; it always refers to a specific area where the species no longer exists. captive Examples: Hawaiian Crow, Scimitar Oryx. Examples: Hawaiian Crow, Scimitar Oryx.Hawaiian CrowScimitar OryxHawaiian CrowScimitar Oryx  Extinct (EX): extensive and appropriate surveys have failed to record any living members. Examples: Thylacine, Dodo, Huia. Examples: Thylacine, Dodo, Huia.ThylacineDodoHuiaThylacineDodoHuia  Data Deficient (DD): a taxon is listed as Data deficient when there is inadequate information to make an assessment of its risk category,  Not evaluated (NE): taxa whose conservation status has not been assessed to date.

13 Video: Penguin Rescue  From ABC News, Biology in the Headlines, 2005 DVD. Videos/penguin_rescue.html

14 SPECIES EXTINCTION  Estimates of future extinction vary due to different assumptions about  total species number  the proportion found in the tropics  rate of clearance of tropics  reliability of methods

15 SPECIES EXTINCTION  Percentage of various species types threatened with premature extinction from human activities. Figure 11-5

16 SPECIES EXTINCTION  Scientists use models to estimate the risk of particular species becoming extinct or endangered. Figure 11-6

17 SPECIES EXTINCTION Estimates of future extinctions are limited: Not all species are known or studied Not all species are known or studied Total human impact is unclear Total human impact is unclear Current rate of extinction = 1,000-10,000x rate of normal background extinctionCurrent rate of extinction = 1,000-10,000x rate of normal background extinction Current model – 20% plant species gone by 2030, 50% by 2099Current model – 20% plant species gone by 2030, 50% by 2099

18 SPECIES EXTINCTION Greater than predicted rates are likely: Exponential population growth Exponential population growth Biologically diverse “hotspots” are already 25-30% loss Biologically diverse “hotspots” are already 25-30% loss Possible colonization sites are being eliminated, degraded and simplified by human activities Possible colonization sites are being eliminated, degraded and simplified by human activities This reduces the rate of speciation = SPECIES CRISISThis reduces the rate of speciation = SPECIES CRISIS

19 IMPORTANCE OF WILD SPECIES Wild species have ecologic and economic value  Causing the premature extinction of species eliminates the services they provide. Medicine, genetic information, recreational value, eco-tourism Medicine, genetic information, recreational value, eco-tourism Male lion skin = $1,000; living male lion = $515,000 in tourism revenue over 7 yearsMale lion skin = $1,000; living male lion = $515,000 in tourism revenue over 7 years Bats = insect control, pollination, seed dispersal (keystone species) Bats = insect control, pollination, seed dispersal (keystone species) INTRINSIC VALUE - an inherent right to exist. Some distinguish between the survival rights among various types of species (plants vs. animals).

20 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION The most important causes of premature extinction, “HIPPO”: Habitat destruction, degradation, and fragmentation (greatest threat to species) Habitat destruction, degradation, and fragmentation (greatest threat to species) Invasive species Invasive species Population growth Population growth Pollution Pollution Overharvest Overharvest

21 Animation: Habitat Loss and Fragmentation PLAY ANIMATION

22 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION  The greatest threat to a species is the loss, degradation, and fragmentation of where it lives. Figure 11-7

23 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION Tropical deforestation is the greatest species eliminator (followed by loss of wetlands and plowing grasslands) Major Habitat Disturbance: Major Habitat Disturbance: AgricultureAgriculture Commercial developmentCommercial development Water developmentWater development RecreationRecreation GrazingGrazing PollutionPollution

24 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION  Endemic species - species found nowhere else on earth and are often found in island habitats.  Habitat islands - habitats surrounded by a different one, such as a national park surrounded by logging, mining, etc. Fragmentation leads to species vulnerability to predators, disease, etc. Fragmentation leads to species vulnerability to predators, disease, etc. Species are limited in their ability to colonize new areas, find mates and food. Species are limited in their ability to colonize new areas, find mates and food.

25 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION  Reduction in ranges of four wildlife species, mostly due to habitat loss and overharvest. Figure 11-8

26 Fig. 11-8a, p. 230 Range 100 years ago Indian Tiger Range today (about 2,300 left)

27 Fig. 11-8b, p. 230 Range in 1700 Black Rhino Range today (about 3,600 left)

28 Fig. 11-8c, p. 230 Probable range 1600 African Elephant Range today

29 Fig. 11-8d, p. 230 Range today (34,000–54,000 left) Asian or Indian Elephant Former range

30 Video: Bachelor Pad at the Zoo  From ABC News, Biology in the Headlines, 2005 DVD. PLAY VIDEO

31 Case Study: A Disturbing Message from the Birds  Human activities are causing serious declines in the populations of many bird species. Figure 11-9

32 Video: Bird Species and Birdsongs PLAY VIDEO

33 Case Study: A Disturbing Message from the Birds  The majority of the world’s bird species are found in South America. Threatened with habitat loss and invasive species. Threatened with habitat loss and invasive species. Figure 11-10

34 HABITAT LOSS, DEGRADATION, AND FRAGMENTATION  70% of the world’s known species of birds are declining.  One in six species is threatened with extinction due to habitat loss and fragmentation.  Nonnative species are the 2 nd greatest threat to birds Excellent environmental indicators: live in every climate and biome, respond quickly to environmental changes, easy to track and count. Excellent environmental indicators: live in every climate and biome, respond quickly to environmental changes, easy to track and count. Birds ecological roles: control rodents and insects, pollination of flowering plants, seed dispersal, and scavengers of dead animals Birds ecological roles: control rodents and insects, pollination of flowering plants, seed dispersal, and scavengers of dead animals

35 INVASIVE SPECIES  Many nonnative species provide us with food, medicine, and other benefits but a a few can wipe out native species, disrupt ecosystems, and cause large economic losses. Kudzu vine was introduced in the southeastern U.S. to control erosion. It has taken over native species habitats. Figure 11-A

36 INVASIVE SPECIES  Many invasive species have been introduced intentionally. Figure 11-11

37 INVASIVE SPECIES  They have no natural predators, competitors, or pathogens in their new habitat. Figure 11-11

38 INVASIVE SPECIES  They can trigger ecological disruptions Wild African honeybee – displaces natives/impact on native plants Wild African honeybee – displaces natives/impact on native plants Formosan termite – from China – swarming, aggressive and destructive Formosan termite – from China – swarming, aggressive and destructive Feral pigs kill livestock, eat crops, spread disease, cause erosion to stream banks, spread disease to livestock Feral pigs kill livestock, eat crops, spread disease, cause erosion to stream banks, spread disease to livestock Feral cats and domestic cats kill about 568 million birds per year. Feral cats and domestic cats kill about 568 million birds per year.

39 INVASIVE SPECIES  The Argentina fire ant was introduced to Mobile, Alabama in 1932 from South America. Most probably from ships. Most probably from ships. No natural predators. No natural predators.  Extremely aggressive  Eliminated about 90% of native ant species,  caused widespread agricultural damage  genetically resistant to pesticides through natural selection. Figure 11-12

40 INVASIVE SPECIES  Prevention is the best way to reduce threats from invasive species, because once they arrive it is almost impossible to slow their spread. Figure 11-13

41 Fig. 11-13, p. 236 Climate similar to habitat of invader Absence of predators on invading species Early successional systems Low diversity of native species Absence of fire Disturbed by human activities Characteristics of Successful Invader Species High reproductive rate, short generation time (r-selected species) Pioneer species Long lived High dispersal rate Release growth-inhibiting chemicals into soil Generalists High genetic variability Characteristics of Ecosystems Vulnerable to Invader Species

42 POPULATION GROWTH, POLLUTION, AND CLIMATE CHANGE  Population growth, affluenza, and pollution have promoted the premature extinction of some species.  Projected climate change threatens a number of species with premature extinction.

43 Pollution  Each year pesticides: Kill about 1/5 th of the U.S. honeybee colonies. Kill about 1/5 th of the U.S. honeybee colonies. 67 million birds. 67 million birds. 6 -14 million fish. 6 -14 million fish. Threaten 1/5 th of the U.S.’s endangered and threatened species. Threaten 1/5 th of the U.S.’s endangered and threatened species. Example of biomagnification of DDT in an aquatic food chain. Figure 11-15

44 OVEREXPLOITATION  Smuggling wildlife: 3 rd largest and most profitable illegal cross-border smuggling activity after arms and drugs (at least 2/3rds die in transit)  More endangered = greater demand  Removal of many top predators – cascade effect  Killing protected species for their valuable parts or selling live to collectors.  Killing predators and pests that bother us or cause economic losses (coyotes, bobcats, black- footed ferret).  Legal and illegal trade in wildlife species used as pets or for decorative purposes.

45 OVEREXPLOITATION  Rhinoceros are often killed for their horns and sold illegally on the black market for decorative and medicinal purposes. Figure 11-16

46 OVEREXPLOITATION  More than 60 bird species, mostly parrots are endangered or threatened because of the wild bird trade.  Amphibians, reptiles, mammals and tropical fish are also being depleted because of pet trade.  Ex-poachers in Thailand are now making more money taking eco-tourists into the forest than they did by poaching hornbills. They also protect these birds from poachers.  Collecting exotic pets and plants (such as orchids and cacti) kill large numbers of them and endanger these species and others that depend on them

47 Case Study: Rising Demand for Bushmeat in Africa  Bushmeat hunting has caused the local extinction of many animals in West Africa.  Can spread disease such as HIV/AIDS and ebola virus. Figure 11-17

48 PROTECTING WILD SPECIES: LEGAL AND ECONOMIC APPROACHES  International treaties have helped reduce the international trade of endangered and threatened species, but enforcement is difficult. One of the most powerful is the 1975 Convention on International Trade of Endangered Species (CITES). One of the most powerful is the 1975 Convention on International Trade of Endangered Species (CITES). Signed by 169 countries, lists 900 species that cannot be commercially traded.Signed by 169 countries, lists 900 species that cannot be commercially traded. Difficult to enforce – varies from country to countryDifficult to enforce – varies from country to country

49 PROTECTING WILD SPECIES: LEGAL AND ECONOMIC APPROACHES  Convention on Biological Diversity (CBD) binds governments to reverse the global decline in biological biodiversity.  United States has not ratified this treaty.  There are no severe penalties or other enforcement mechanisms in place.

50 High Moderate ESA – Endangered Species Act: Program for the conservation of threatened and endangered plants and animals and the habitats in which they are found. Lead federal agencies: the U.S. Fish and Wildlife Service (FWS), U.S. National Oceanic and Atmospheric Administration (NOAA) Fisheries Service. The FWS maintains a worldwide list of endangered species.the U.S. Fish and Wildlife Service (FWS)U.S. National Oceanic and Atmospheric Administration (NOAA) Fisheries Serviceworldwide list of endangered species Includes birds, insects, fish, reptiles, mammals, crustaceans, flowers, grasses, and trees. Prohibits any action that causes a "taking" of any listed species of endangered fish or wildlife; import, export, interstate, and foreign commerce of listed species are all generally prohibited.

51 Case Study: The U.S. Endangered Species Act  One of the world’s most far-reaching and controversial environmental laws is the 1973 U.S. Endangered Species Act (ESA). Forbids federal agencies (besides defense department) to carry out / fund projects that would jeopardize an endangered species. Forbids federal agencies (besides defense department) to carry out / fund projects that would jeopardize an endangered species. Makes it illegal for Americans to engage in commerce associated with or hunt / kill / collect endangered or threatened species. Makes it illegal for Americans to engage in commerce associated with or hunt / kill / collect endangered or threatened species. Based on biological facts/protects habitats (HCPs – inadequate science, many are political compromises) Based on biological facts/protects habitats (HCPs – inadequate science, many are political compromises)

52 The U.S. Endangered Species Act  Biodiversity hotspots in relation to the largest concentrations of rare and potentially endangered species in the U.S.  Political pressure/lack of funds limit (79% of plans not implemented) Figure 11-18

53 Endangered Species  Because of scarcity of inspectors, probably no more than 1/10 th of the illegal wildlife trade in the U.S. is discovered. Figure 11-19

54 PROTECTING WILD SPECIES: THE SANCTUARY APPROACH  The U.S. has set aside 544 federal refuges for wildlife, but many refuges are suffering from environmental degradation. Pelican Island was the nation’s first wildlife refuge. Figure 11-20

55 PROTECTING WILD SPECIES: THE SANCTUARY APPROACH  Gene banks, botanical gardens and using farms to raise threatened species can help prevent extinction, but these options lack funding and storage space.  Zoos and aquariums can help protect endangered animal species by preserving some individuals with the long-term goal of reintroduction, but suffer from lack of space and money.  Many reintroductions fail: no suitable habitat, not able to survive, renewed overhunting/capture  Large population is needed to maintain capacity for evolution

56 Video: Hsing Hsing Dies  From ABC News, Biology in the Headlines, 2005 DVD. PLAY VIDEO

57 RECONCILIATION ECOLOGY  Reconciliation ecology – find ways to share places we dominate with other species. Replacing monoculture grasses with native species. Replacing monoculture grasses with native species. Maintaining habitats for insect eating bats can keep down unwanted insects. Maintaining habitats for insect eating bats can keep down unwanted insects. Reduction and elimination of pesticides to protect non-target organisms (such as vital insect pollinators). Reduction and elimination of pesticides to protect non-target organisms (such as vital insect pollinators). Maintain diverse yards with natives/ biodiverse gardens/rooftop gardens Maintain diverse yards with natives/ biodiverse gardens/rooftop gardens Bluebirds project & Golden State Park Bluebirds project & Golden State Park

58 Using Reconciliation Ecology to Protect Bluebirds  Putting up bluebird boxes with holes too small for (nonnative) competitors in areas where trees have been cut down have helped reestablish populations.

59 Fig. 11-21, p. 246 Do not buy furs, ivory products, and other materials made from endangered or threatened animal species. Do not buy wood and paper products produced by cutting remaining old-growth forests in the tropics. Do not buy birds, snakes, turtles, tropical fish, and other animals that are taken from the wild. Do not buy orchids, cacti, and other plants that are taken from the wild. Spread the word. Talk to your friends and relatives about this problem and what they can do about it. http://tolweb.org/onlinecontributors/app?service =external/ViewImageData&sp=23923 What Can You Do? Protecting Species


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