Sustaining Biodiversity: The Species ApproachSustaining Biodiversity: The Species Approach
G. Tyler Miller’sLiving in the Environment
14th Edition
Modified by Mr. Manskopf
Chapter 12
G. Tyler Miller’sLiving in the Environment
14th Edition
Modified by Mr. Manskopf
Chapter 12
Edward AbbeyEdward 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…
Chapter 12 Key ConceptsChapter 12 Key Concepts
Human effects on extinction rates Human effects on extinction rates
Understanding biodiversity and extinction Understanding biodiversity and extinction
How human activities endanger wildlife How human activities endanger wildlife
Preventing extinction Preventing extinction
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.
Section 1 Key IdeasSection 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?
Species ExtinctionSpecies Extinction
Local extinction: species no longer found in a Specific location.
Local extinction: species no longer found in a Specific location.
Ecological extinction: when so few are locatedthey no longer play a role in a ecosystem.
Ecological extinction: when so few are locatedthey no longer play a role in a ecosystem.
Biological extinction: when species no longerexists anywhere. GONE FOREVER!
Biological extinction: when species no longerexists anywhere. GONE FOREVER!
Endangered and Threatened SpeciesEndangered and Threatened Species
Endangered species: has so few individualsit may soon be extinct.
Endangered species: has so few individualsit may soon be extinct.
Threatened (vulnerable) species: decliningnumbers mean it may soon become endangered.
Threatened (vulnerable) species: decliningnumbers mean it may soon become endangered.
Florida manatee
Northern spotted owl (threatened)
Gray wolf Florida panther Bannerman's turaco (Africa)
Certain characteristics make some species more vulnerable…big, slow, tasty or have valuable parts (ie. Tusks)
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.
How do biologists estimate extinctionsHow 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.
Extinction RatesExtinction Rates
Background (natural) rate of extinction Background (natural) rate of extinction
Massextinction
Massextinction
Extinction spasm
Extinction spasm
Fig. 5-9 p. 96
How do biologists estimate extinctionsHow 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
Problems Estimating Extinction RatesProblems Estimating Extinction Rates
Extinction not easily documented over time
Many species remain unidentified
Little is known about most identified species
Extinction not easily documented over time
Many species remain unidentified
Little is known about most identified species
Estimating Extinction Rates: Look up for homework page 228Estimating Extinction Rates: Look up for homework page 228
Species-area relationships
Population viability analysis (PVA)
Minimum viable population (MVP)
Minimum dynamic area (MDA)
Species-area relationships
Population viability analysis (PVA)
Minimum viable population (MVP)
Minimum dynamic area (MDA)
How are humans affecting extinction rates?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
How are humans affecting extinction rates?How are humans affecting extinction rates?
0.1% to 1% seen as conservative estimate:
1) Likely to increase due to population and footprint
2) “Hot Spots” under attack
3) Simplifying ,many ecosystems… monoculture
Estimates 20% of world’s plants and animals gone by 2030 and 50% by end of century
How are humans affecting extinction rates?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.”
Section 2 Key IdeasSection 2 Key Ideas
• Why should we preserve wild species?• What is the intrinsic value of a species?
Importance of Wild SpeciesImportance 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?
Importance of Wild SpeciesImportance of Wild Species
Instrumental Value: based upon the usefulness of species (economic and ecological)
• Food crops• Fuels• Paper• Medicines• Genetic Information• Recreation (eco tourism)
Importance of Wild SpeciesImportance of Wild SpeciesWhy 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.
Intrinsic Value of Species 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?
Importance of Wild SpeciesImportance of Wild Species
Rebuilding biodiversity is slowInstrumental valueGenetic informationEco-tourismEcological valueIntrinsic value (biophilia)
Rebuilding biodiversity is slowInstrumental valueGenetic informationEco-tourismEcological valueIntrinsic value (biophilia)
Section 3 Key IdeasSection 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?
Causes of Depletion of Wild SpeciesCauses of Depletion of Wild Species
Human population growthHuman population growth
Endangered centers of biodiversityEndangered centers of biodiversity
Increasing per capita resource useIncreasing per capita resource use
Environmental destructionEnvironmental destruction
Spread of opportunistic speciesSpread of opportunistic species
Causes of Premature Extinction of Wild SpeciesCauses of Premature Extinction of Wild Species
Fig. 12-6 p. 231
Habitat Loss and DegradationHabitat Loss and Degradation
Greatest threat to species“HIPPO”
Habitat destruction Invasive speciesPopulation (humans) growthPollutionOverharvesting
Greatest threat to species“HIPPO”
Habitat destruction Invasive speciesPopulation (humans) growthPollutionOverharvesting
Habitat Fragmentation 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.
Bird ExtinctionsBird 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)
Bird ExtinctionsBird Extinctions
• Hooked on fishing lines• Collide with powerlines,
skyscrapers, wind turbines• Oil spills• Pesticides • Swallow lead from bullets
Bird ExtinctionsBird 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
Section 4 Key IdeasSection 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
Nonnative Species Deliberately IntroducedNonnative Species Deliberately Introduced
We depend upon nonnative species for:
• Economic systems
• Food
• Shelter
• Medicine
• AestheticsCorn, wheat, rice, livestock, etc.
(98% of food supply in U.S.)
Nonnative Species Deliberately IntroducedNonnative 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
Nonnative Species Deliberately IntroducedNonnative 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
Accidentally Introduces SpeciesAccidentally Introduces Species
Growing Number of Accidentally Introduced Species Causing:
• Economic Damage
• Ecological Damage
• Aircraft• Ballast Water• Cargo• Soil in car tires
Prevention Best To Reduce Threats
Threats from Nonnative SpeciesThreats from Nonnative Species
ArrivalArrival
Roles of non-native speciesRoles of non-native species
Examples (p. 235)Examples (p. 235)
See Case Study p. 237See Case Study p. 237
Fig. 12-12 p. 238Fig. 12-12 p. 238
PreventionPrevention
Fig. 12-12 p. 238
Section 5-6 Key IdeasSection 5-6 Key Ideas
• What is the threat from poaching and hunting?
• Case study: Bushmeat
• What are other threats to endangered species?
• CNN Video
Bushmeat: such as gorilla head
Source of protein for local populations
Sometimes sold internationally
Other Extinction ThreatsOther Extinction Threats
Hunting and PoachingHunting and Poaching
Predators and Pest ControlPredators and Pest Control
Exotic Pets and Decorative PlantsExotic Pets and Decorative Plants
Climate Change and PollutionClimate Change and Pollution
Section 7 and 8 Key IdeasSection 7 and 8 Key Ideas
• How can laws protect species…both internationally and in the U.S.?
• What are critical habitat designation and recovery plans?
International Laws and TreatiesInternational Laws and Treaties
1975 Convention on International Trade in Endangered Species (CITES)
• 160 countries
• 900 species
• Illegal to trade wildlife specimens
• Limited success (varies by country)
U.S. LawsU.S. Laws
1900 Lacey Act: prohibits transporting wild animals across state lines
1973 Endangered Species Act (ESA): one of the world most far reaching controversial environmental laws
U.S. LawsU.S. Laws ESA:
• US Fish and Wildlife Service (on land) National Marine Fisheries Service (in water)
• ID and LIST Endangered and Threatened species in need of help
• Must be based on biological factors ALONE… no economic or political
U.S. LawsU.S. LawsESA:
• Forbids any U.S. Government funding or involvement that would hurt species or habitat
• Private landowners fine up to $100,000 and imprisonment
• Illegal to sell or buy product made from species
• Can not be hunted, killed or injured
U.S. LawsU.S. LawsESA:
• 1973-2004: 92 to 1,260 species listed
• 37 Species removed (14 recovery, 8 extinctions, rest discovered more)
• 60% plants, 40% animals
• TNC says 1/3rd of all U.S. species…30,000 not 1,260
Critical Habitat Designation Critical Habitat Designation ESA:
• Requires protecting critical habitat
• Developing recovery plan
Lack of funding inhibit some plans (1/3rd of species have plan)
2001 Bush stopped listings
Private Property RightsPrivate Property Rights
Should the U.S. government compensate landowners when Endangered species decreases the economic value of their land?
Arguments Yes and No: Read pages 242-243
Private Property RightsPrivate Property RightsHow can the government
encourage private landowners to protect species?
• National Association of Homebuilders… How to Avoid ESA issues
• Habitat Conservation Plans
Protecting Wild Species: The Research and Legal ApproachesProtecting Wild Species: The Research and Legal Approaches
International Treaties: CITES and CBD International Treaties: CITES and CBD
U.S. National Laws: Lacey ActEndangered Species
Act
U.S. National Laws: Lacey ActEndangered Species
Act Habitat recovery plans Habitat recovery plans
Endangered Species ActEndangered Species Act
Private versus public poverty rights
Win-win compromises
Weaken or strengthen the Act?
Private versus public poverty rights
Win-win compromises
Weaken or strengthen the Act?
Protecting Wild Species: The Sanctuary ApproachProtecting Wild Species: The Sanctuary Approach
Wildlife refuges and protected areas Wildlife refuges and protected areas
Zoos and Aquariums Zoos and Aquariums
Gene banks, botanical gardens, and farms Gene banks, botanical gardens, and farms
Reconciliation EcologyReconciliation Ecology
Establishing and maintaining new habitats Establishing and maintaining new habitats
Being good neighbors to wildlife Being good neighbors to wildlife
Reward voluntary conservation efforts Reward voluntary conservation efforts
See Case Study p. 248