1. Evaluating Biodiversity & Vulnerability
IB Syllabus: – 4.2.7
AP syllabus
Ch.22, 23, 24
Planet in Peril – episode 1

3. Syllabus Statements
4.2.1: Identify factors that lead to a loss of diversity
4.2.2: Describe the perceived vulnerability of tropical rainforests and their relative value in contributing to global biodiversity
4.2.3: Discuss current estimates of numbers of species and past and present rates of species extinction
4.2.4: Describe and explain the factors that may make species more or less prone to extinction

4. 4.2.5: Outline the factors used to determine a species’ Red List conservation status
4.2.6: Describe the case histories of three species: one that has become extinct, another that is currently endangered, and a third whose conservation status has been improved by intervention
4.2.7: Describe the case history of a natural area of biological significance that is threatened by human activities

5. How is biodiversity lost?
Natural Processes
Natural hazards (volcanoes, drought, mudslide)
Global catastrophies (ice age, meteor impact)
Human Processes
Habitat degradation, fragmentation & loss
Introduction/escape of nonnative species, genetically modified organisms, monoculture
Pollution
Hunting, collecting, harvesting. overfishing

7. Rain Forests – A Case Study
2% of the land surface with 50-80% of the terrestrial species
Characterized by warm constant temperature, high humidity & rainfall
Vertical stratification provides niche diversification
Decomposition rates are extremely fast  little litter, thin nutrient poor soil
Nutrients stored in biomass of organisms

9. The threats to rainforests
Most of destruction since 1950
Brazil has ½ remaining world rainforest
At current rates of deforestation Brazil’s rainforest will be gone in years
Total loss yearly to deforestation is 50,000 to 170,000 km2
1.5 ACRES LOST PER SECOND worldwide
Cutting & degradation at even faster rates

11. Highest average annual deforestation of primary forests, 2000-2005, by area. All countries
1 Brazil -3,466,000
2 Indonesia -1,447,800
3 Russian Federation -532,200
4 Mexico -395,000
5 Papua New Guinea -250,200
6 Peru -224,600
7 United States of America -215,200
8 Bolivia -135,200
9 Sudan -117,807
10 Nigeria -82,000

12. Amazon Rainforest
The Amazonian Rainforest covers over a billion acres, encompassing areas in Brazil, Venezuela, Columbia and the Eastern Andean region of Ecuador and Peru.
If Amazonia were a country, it would be the ninth largest in the world.
The Amazon Rainforest has been described as the "Lungs of our Planet" because it provides the essential environmental world service of continuously recyling carbon dioxide into oxygen.
More than 20 percent of the world oxygen is produced in the Amazon Rainforest.
More than half of the world's estimated 10 million species of plants, animals and insects live in the tropical rainforests. One-fifth of the world's fresh water is in the Amazon Basin.
One hectare (2.47 acres) may contain over 750 types of trees and 1500 species of higher plants.

14. Amazon effects 1/3 of rainforest destruction from shifting cultivation
Rest cleared for pasture- then planted with African grasses for cattle
When pasture price exceeds forest prices  incentive for land clearing
Government subsidized agriculture and colonization
Improved infrastructure for transport
In Brazil alone, European colonists have destroyed more than 90 indigenous tribes since the 1900's.

15. Plants uniquely adapted to the conditions there

17. Why rainforests vulnerable
Ecology
Pollinator relationships – reproduction depends on other organisms
Poor, thin soils – easily eroded once trees removed, little chance for regrowth
Location
Surrounded by rapid population growth of developing countries – pollution, waste, space
Poor economy benefits from any resources that are harvestable

18. General Pressures on Rainforests
Economic – raw materials, exports, cattle, oil & gas
Socio-political – Pressures of population growth, subsidize tree plantations, colonization
Ecological – Invasive species, climate change, soil degradation

19. Revolve around Population Growth Poverty Government Policy
Bromeliad
Orchid
Roads
Logging
Cash crops
Cattle ranching
Tree plantations
Flooding from dams
Mining
Oil drilling
Unsustainable peasant farming
Primary Causes:
Rapid population growth
Exploitive government policies
Poverty
Exports to developed counties
Failure to include ecological services
in evaluating forest resources
Toucan
Scarlet
macaw
Golden lion
marmoset
Blue morpho butterfly
Secondary Causes:
Interconnected Causes
Of Degradation &
Destruction of Tropical
Rainforests
Revolve around
Population Growth
Poverty
Government Policy

21. Rodonia Brazil:
Acquired by the Advance Spaceborne Thermal Emission and Reflection Radiometer
(ASTER) on August 24, 2000, the false-color image combines near-infrared, red, and
green light. Tropical rainforest appears bright red, while pale red and brown areas
represent cleared land. Black and gray areas have probably been recently burned.
The Jiparaná River appears blue.

22. Secondary results Clearing rainforests degrades tropical rivers
Water more turbid, silts river bottoms, nutrient overload in estuaries, smothers offshore coral reefs
Accelerates flooding & reduces aquifer recharge
Affect precipitation patterns
Flow of moisture to downwind areas is reduced

23. Why are they special? Or…
Why should we care?
Some biogeographers claim that loss of tropical rainforests is no more important than loss of old growth forests in EU & NA
1. Important ecological & environmental services
2. Instrumental values  medicines from plants
3. Cultural value

24. Instrumental Values of Tropical Forest Ecosystems
Use Values
Nonuse Values
Direct Use Values
Indirect Use
Values
Option Values
Existence Values
Future products:
Timber and other
building materials
Protection of
biological
diversity
Soil fertility
Medicines
Flood control
Fuelwood
Genetic
resources
Maintaining
cultures of local
people
Water purification
Medicinal plants
Pollution control
Biological
insights
Edible wild fruits
and plants
Continuing
ecological and
evolutionary
processes
Recreation and
tourism
Food sources
Fiber
Education
Building
supplies
Ecological
services (pest
control,
pollination)
Future ecological
services
Genetic
information

25. Cultural Extinction
250 million people in 70 countries from indigenous rainforest cultures
Hunting & Gathering, Sustainable Agriculture
Remaining tribal people are disappearing with their lands
Irreplacable loss of ecological & cultural knowledge – most medicine men 70+ years old
Need protection & ownership of land to survive
BUT  that stands in the way of progress

26. The Yanomami
South America
The Huli
Papua New Guniea
The Pygmies
Central Africa

27. Prevention Restoration
Protect most diverse and
endangered areas
Educate settlers about sustainable
agriculture and forestry
Phase out subsidies that encourage
unsustainable forest use
Add subsidies that encourage
sustainable forest use
Protect forests with debt-for-nature
swaps, conservation easements,
and conservation concessions
Certify sustainably grown timber
Reduce illegal cutting
Reduce poverty
Slow population growth
Reforestation
Rehabilitation
of degraded
areas
Concentrate
farming and
ranching on
already-cleared

28. Biodiversity will decrease from…
Environmental Stress
Large environmental disturbance
Extreme environmental conditions
Severe limitation of an essential nutrient, habitat, or other resource
Introduction of a nonnative species
Geographic isolation

29. Water use and pollution
and soil nutrient loss
Freshwater
supply and demand
Food supply
and demand
Water availability
Changes in
water supply and temperature
Deforestation
Changes in
precipitation
and temperature
Erosion,
pollution, and
changes in
water flow
CO2, CH4,
N2O emissions
Habitat change
and fragmentation
of habitat
Forest product
supply and demand
Climate change
CO2 emission
Changes in
transpiration
and albedo
Loss and
fragmentation
of habitat
Loss and
fragmentation
of habitat
Loss
of crop
genetic
diversity
Habitat
change
Reduced
resistance
to change
Biodiversity loss

30. About 1.5 - 10 million Species live on Earth
Estimates of the Numbers of Species in the World
Groups of Organisms
Species described
Maximum estimates
Most conservative estimates
Viruses
5,000
500,000
Bacteria
4,000
3,000,000
400,000
Fungi
70,000
1,500,000
1,000,000
Algae
40,000
10,000,000
200,000
Plants
250,000
300,000
Vertebrates
45,000
50,000
Nematodes
15,000
Molluscs
180,000
Crustaceans
150,000
Arachnids
75,000
750,000
Insects
950,000
100,000,000
8,000,000
Source: World Conservation Monitoring Centre, Global Biodiversity - Status of the Earth's Living Resources, 1992.
18000 to species lost per year
1 species lost every 20 minutes
Estimates differ but over 50 species lost per day is probably accurate
Stop the Clock –

31. Current Classification of Species
67%
Secure or
apparently
secure 1%
Other
16%
Vulnerable 8%
Imperiled 7%
Critically
imperiled
Probably extinct
Current Classification of Species

32. How can we reduce biodiversity loss?
2 main approaches – ecosystem or species directed
Preventing premature extinction of species
Preserving & restoring ecosystems which provide habitats and resources for the world’s species

33. The Ecosystem Approach
The Species Approach
The Ecosystem Approach
Goal
Goal
Protect species from
premature extinction
Protect populations of
species in their natural
habitats
Strategies
Strategy
Identify endangered species
Protect their critical habitats
Preserve sufficient areas
of habitats in different
biomes and aquatic
systems
Tactics
Tactics
Legally protect endangered species
Manage habitat
Propagate endangered species in captivity
Reintroduce species into suitable habitats
Protect habitat areas through private purchase or government action
Eliminate or reduce populations of alien species from protected areas
Manage protected areas to sustain native species
Restore degraded ecosystems

34. Endangered vs. Threatened
Organisms are classified for conservation purposes Traditionally into 2 groups
Endangered
So few individuals that it could become extinct over all of its natural range
Without protection  critically endangered  extinct
Threatened
Still abundant in range but declining numbers
Ecological warning signs

35. Red Data Books
List the species in the red – the ones most in jeopardy of extinction
Various factors contribute to identifying species as threatened, of concern, endangered, extinct
Examples - population size, reduction of population size, numbers of mature individuals, geographic range and degree of fragmentation, quality of habitat, area of occupancy, probability of extinction

36. Figure 22-7 (1) Page 564 Florida manatee
Northern spotted owl (threatened)
Gray wolf
Florida panther
Bannerman's turaco (Africa)
Devil's hole pupfish
Snow leopard
(Central Asia)
Symphonia
(Madagascar)
Black-footed ferret
Utah prairie dog
(threatened)
Ghost bat
(Australia)
California condor
Black lace cactus
Black rhinoceros
(Africa)
Oahu tree snail

37. Figure 22-7 (2) Page 565 Grizzly bear (threatened) Kirtland's warbler
White top pitcher plant
Arabian oryx
(Middle East)
African elephant
(Africa)
Mojave desert tortoise (threatened)
Swallowtail butterfly
Humpback chub
Golden lion tamarin (Brazil)
Siberian tiger
(Siberia)

38. Figure 22-7 (3) Page 565 West Virginia spring salamander Giant panda
(China)
Whooping crane
Knowlton cactus
Blue whale
Mountain gorilla
(Africa)
Pine barrens
tree frog (male)
Swamp pink
Hawksbill sea turtle
El Segundo blue butterfly

39. EXTINCTION

40. Evidence from the past
The fossil record remains first and foremost among the databases that document changes in past life on Earth.
The fossil record clearly shows changes in life through almost any sequence of sedimentary rock layers.
Successive rock layers contain different groups or assemblages of fossil species.

42. 3 Types of Extinction
Local extinction (extirpation)  species no longer found in an area where it was once found
Still found elsewhere (= population extinction)
Ecological extinction  so few members of a species are left that it can no longer play its ecological role in the ecosystem
Biological extinction  species is no longer found anywhere on the earth

44. Mass Extinctions Epoch Cause Species Lost Precambrian Glaciation
Stromatolites
Cambrian
O2 Depletion
Olnellids
Ordovician
Glaciation of Gondwana
Brachiopods
Devonian
Meteor, Glaciation
Early corals
Permian
Pangea
Trilobites
End Cretaceous
Meteor, Volcanoes
Dinosaurs
Holocene
Humans
All forms

46. Permian mass Extinction
Permian Period ( million years ago)  Formation Of Pangea
Terrestrial faunal diversification occurred in the Permian
90-95% of marine species became extinct in the Permian (largest extinction in history)
- Causes? = Formation of Pangea reduced continental shelf area, glaciation, Volcanic eruptions

48. The End-Cretaceous (K-T) Extinction
- Numerous evolutionary radiations occurred during the Cretaceous ( million years ago)  1st appearance of dinosaurs, mammals, birds, angiosperms
- A major extinction occurred at the end of the period - 85% of all species died in the End-Cretaceous (K-T) extinction (2nd largest in history)
- Causes? = Meteor impact in the Yucatan, Volcanic eruption  both supported geolocially, cause climate change, atmospheric changes

51. Extinction Rates
Biologists estimate that 99.9% of all species ever in existence are now extinct
Background extinction – local environmental changes cause species to disappear at low rate
mass extinction – catastrophic, widespread (25 – 75% of existing species
mass depletion – higher than background but not mass
Cause temporary biodiversity reductions  but create vacant niches for new species to evolve
5 million years of adaptive radiation to rebuild diversity after extinction

52. Premature extinction from human causes
Passenger pigeon
Great auk
Dodo
Dusky seaside sparrow
Aepyornis
(Madagascar)
Main factors  Overhunting, Habitat Destruction &
Introduction of Exotic Species

53. Differences in Cause of Extinction
Historically most mass extinctions were caused by
Catastrophic Agents- such as meteorite impacts and comet showers,
Earth Agents- such as volcanism, glaciation, variations in sea level, global climatic changes, and changes in ocean levels of oxygen or salinity
Currently a mass extinction is being caused by the actions of 1 species  Us

54. Which species are most vulnerable?
Vulnerability of species affected by …
Numbers – low numbers = automatic risk
Degree of specialization = generalists adapt better than specialists
Distribution = widely distributed organisms, may migrate out of harms way & different effects by area
Reproductive potential – if low = vulnerable
Reproductive behaviors – how complex, picky, …
Trophic level – higher are more vulnerable to biomagnification & trophic cascades

55. Fixed migratory patterns Commercially valuable
Characteristic
Examples
Low reproductive rate
(K-strategist)
Specialized niche
Narrow distribution
Feeds at high trophic
level
Fixed migratory patterns
Rare
Commercially valuable
Large territories
Blue whale, giant panda,
rhinoceros
Everglades kite
Many island species,
elephant seal, desert pupfish
Bengal tiger, bald eagle,
grizzly bear
Blue whale, whooping crane,
sea turtles
African violet, some orchids
Snow leopard, tiger,
elephant, rhinoceros,
rare plants and birds
California condor, grizzly
bear, Florida panther

56. Range 100 years ago
Range today
(about 2,300 left)
Indian Tiger

57. Range in 1700
Range today
(about 2,400 left)
Black Rhino

58. Probable range 1600
Range today
(300,000 left)
African Elephant

59. Asian or Indian Elephant
Former range
Range today
(34,000–54,000 left)
Asian or Indian Elephant

60. Vulnerability of ecosystems
Diversity  at species, genetic, ecological or functional levels
** Remember, Diversity = Stability **
Resilience  Ability of a living system to restore itself to original condition after being exposed to a minor outside disturbance
Inertia  ability of a living system to resist being disturbed or altered

61. Temperate broadleaf forests 94%
Biome
% of Area Disturbed
Temperate broadleaf forests
94%
Temperate evergreen forests
94%
Temperate grasslands
72%
Mixed mountain systems
71%
Tropical dry forests
70%
Subtropical and temperate rain forests
67%
Cold deserts and semideserts
55%
Mixed island systems
53%
Warm deserts and semideserts
44%
Tropical humid forests
37%
Tropical grasslands
26%
Temperate boreal forests
18%
Tundra
0.7%

62. Leading causes of wildlife depletion & extinction
Habitat loss, fragmentation or degradation
Agriculture, urban development, pollution
Prevent dispersal, mating, gene flow
Deliberate or accidental introduction of non-native species
Rapid reproduction, no competitors, no predators, upset energy flow

63. Habitat
loss
Habitat
degradation
Overfishing
Basic Causes
Introducing
nonnative
species
Climate
change
Population growth
Rising resource use
No environmental accounting
Poverty
Commercial
hunting
and
poaching
Pollution
Sale of
exotic pets
and
decorative
plants
Predator
and
pest control

64. Case Studies - Elephants
Endangered
Ecological pressures – shrinking habitat
Socio-political pressures – recovery of elephants in smaller habitats = widespread habitat destruction, other species now poached for ivory
Economic pressures – poaching for ivory
Ecological Role – keystone species, maintains grassland community by removing trees
Consequences – loss of ecosystem type

66. Case Studies – Passenger Pigeon
Extinct September 1, 1914
Ecological pressures – clearing virgin forests for agriculture lost food & nests, 1 egg laid per year
Socio-political pressures – Supply meat for growing east coast cities
Economic pressures – easy capture in large dense flocks, roosts markets in the east
Ecological Role – once most numerous bird on the planet
Consequences – linked to spread of lyme disease

68. Case Studies – American Alligator
Recovered June
Ecological pressures – shrinking habitat
Socio-political pressures – alligator nuisance, sustainable use, tourism
Economic pressures – confused with American Crocadile hunted for skins
Ecological Role – keystone predator, gator holes in everglades, top carnivore
Consequences – loss of fish & bird populations & change whole everglades ecosystem structure / now healthy systems

69. Alligator mississippiensis

70. Remember
That current changes in species numbers will be exacerbated by global warming

72. When is endangered really “in danger”
Is there a number where the population is too small to survive?
MVP = minimum viable population  the smallest number of individuals necessary to ensure the survival of a population in a region for a specified timer period
Time range typically years
Most indications are that a few thousand individuals is the MVP if time span is > 10 years

73. Genetic Bottlenecks
If populations recover from times with small numbers other problems can persist
Genetic bottlenecks
Think of a traffic bottleneck  many cars approach and stop, only a few get through.
Same with genes – genetic diversity is dramatically reduced
When populations are reduced to small numbers interbreeding occurs and genetic diversity plummets

75. Cheetahs
A few thousand years ago cheetahs experienced a population crash
They have since recovered but they are almost all genetically identical
Why is this a problem?
Inbreeding increased the chances of deformity from recessively inherited diseases
Identical genes gives identical vulnerability to disease
Weakened physiology – exaggerated recovery time from activity makes them vulnerable

76. References