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Chapter 38
Conservation Biology
PowerPoint Lectures for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
Lecture by Brian R. Shmaefsky
Copyright © 2009 Pearson Education, Inc.
Introduction: Saving the Tiger
 Conservation biology is a goal-oriented science
– It seeks to counter the biodiversity crisis
– It can focus on a single species
– It can also protect many species at once by preserving
habitats and ecosystems
 Conservation biology touches all levels of ecology
– From a single tiger
– To the forest it roams
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THE BIODIVERSITY CRISIS
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38.1 Biodiversity is a vital resource that is being
lost
 Scientists estimate that the Earth has anywhere
from 1.8 to 200 million species
– It is difficult to estimate species loss
– Species loss may be 1,000 times higher than in the past
100,000 years
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38.1 Biodiversity is a vital resource that is being
lost
 Scientists are concerned about the ecological
changes that underlie biodiversity loss
– Ecologists point out the “services” provided by the
biodiversity of ecosystems
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38.2 Biodiversity includes genetic, species, and
ecosystem diversity
 Biodiversity has three levels
– Genetic diversity
– Species diversity
– Ecosystem diversity
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38.2 Biodiversity includes genetic, species, and
ecosystem diversity
 Endangered species
– One that is “in danger of extinction throughout all or a
significant portion of its range”
– Protected by Endangered Species Act
 Threatened species
– Those likely to become endangered in the foreseeable
future
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38.2 Biodiversity includes genetic, species, and
ecosystem diversity
 93% of coral reefs were damaged by human
activities
 40–50% of the reefs are home to one-third of
marine fish species
 These fish could be lost in the next 30 to 40 years
Video: Coral Reef
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38.3 Habitat destruction, invasive species, and
overexploitation are major threats to
biodiversity
 Human alteration of habitats poses the greatest
threat to biodiversity
 Habitation alteration is caused by
– Agriculture
– Urban development
– Forestry
– Mining
– Environmental pollution
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38.3 Habitat destruction, invasive species, and
overexploitation are major threats to
biodiversity
 Invasive species rank behind habitat destruction as
a threat to biodiversity
 Invasive species
– Compete with native species
– Prey on native species
– Parasitize native species
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38.3 Habitat destruction, invasive species, and
overexploitation are major threats to
biodiversity
 Overexploitation is the third major threat to
biodiversity
– Overharvesting has threatened
– Rare trees
– Fish
– Bison
 Hunting of wild animals for bushmeat is depleting
biodiversity worldwide
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38.4 CONNECTION: Pollution of the
environment compounds our impact on other
species
 The global water cycle can transport pollutants
– Pesticides used on land
– Sulfur and nitrogen oxides emitted into the atmosphere
 Gradually thinning ozone layer
– Release of chlorofluorocarbons from aerosol cans and
manufacturing
 Nutrient pollution from fertilizer and wastes
– Linked to summer “dead zone” in the Gulf of Mexico
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38.4 CONNECTION: Pollution of the
environment compounds our impact on other
species
 Pollutants in a food chain can lead to biological
magnification
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Concentration
of PCBs
Herring
gull eggs
124 ppm
Lake trout
4.83 ppm
Smelt
1.04 ppm
Zooplankton
0.123 ppm
Phytoplankton
0.025 ppm
38.5 CONNECTION: Rapid warming is changing
the global climate
 The scientific debate about global warming is over
– Global temperature has risen
– 0.8°C in the last 100 years
– 0.6°C of that increase occurred in the last three decades
– 2 to 4.5°C increases are likely by the end of the 21st century
 Global warming most evident in arctic
– Shrinking sea ice
– Thinning ice sheets
– Melting permafrost
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–2
–1.6 –1.2
–.8
–.4
–.2
.2
.4
.8
1.2
1.6
2.1
1938
1981
2005
38.6 CONNECTION: Human activities are
responsible for rising concentrations of
greenhouse gases
 Atmospheric CO2 did not exceed 300 ppm for
650,000 years
 Atmospheric CO2 is approximately 385 ppm today
 High levels of methane and nitrous oxide also trap
heat
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2000
1800
Carbon Dioxide (CO2)
Methane (CH4)
Nitrous Oxide (N2O)
350
1600
1400
1200
300
1000
800
250
600
0
500
1000
Year
1500
2000
CH4 (ppb)
CO2 (ppm), N2O (ppb)
400
Atmosphere
Photosynthesis
Fossil
fuel
Ocean
38.7 Global climate change affects biomes,
ecosystems, communities, and populations
 Terrestrial biomes determined by temperature and
rainfall
– Changing as a consequence of global warming
– Distributions of populations and species also changing
– Disappearance of many species being caused by
changing climate
– Climate change affects seasonal events in some plants
and animals
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38.8 EVOLUTION CONNECTION: Global
climate change is an agent of natural selection
 Global climate change drives natural selection of
some organisms
– Most of this selection is attributed to phenotypic
plasticity
– Altering phenotype in response to environmental conditions
– Within the normal range of genetic expression
– Can involve genetic shifts that change a species
– Prevents extinction of some species
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38.8 EVOLUTION CONNECTION: Global
climate change is an agent of natural selection
 Red squirrels in Canada
– Natural selection to coordinate breeding time with food
availability
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CONSERVATION BIOLOGY
AND RESTORATION ECOLOGY
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38.9 Protecting endangered populations is one
goal of conservation biology
 Habitat loss
– Population fragmentation
– A harmful effect of habitat loss
– Splitting and isolation of portions of populations
– Can lead to extinctions
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38.9 Protecting endangered populations is one
goal of conservation biology
 Proactive conservation strategies attempt to stop
declines in populations
– Recovery of the red-cockaded woodpecker
– From near-extinction to sustainable populations
– Results from providing its key habitat factors
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38.10 Sustaining ecosystems and landscapes is a
conservation priority
 Conservation biology priority
– Past efforts
– Saving individual species
– Today
– Biodiversity of ecosystems
 Landscape ecology
– Dynamics of a collection of ecosystems
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38.10 Sustaining ecosystems and landscapes is a
conservation priority
 Edges can fragment ecosystems
 Fragmentation is corrected with movement
corridors
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38.11 Protected areas are established to slow the
loss of biodiversity
 Conservation biology focuses on biodiversity hot
spots
– Have a large number of endangered and threatened
species
– Have a concentration of endemic species
 Hot spot designation favors the most noticeable
organisms
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Equator
38.11 Protected areas are established to slow the
loss of biodiversity
 Migratory species pose a special problem for
conservationists
– Monarch butterflies occupy many areas
– Sea turtles travel great distances
 Reserves are set up to protect biodiversity
– 7% of world’s land is in various forms of reserves
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38.12 Zoned reserves are an attempt to reverse
ecosystem disruption
 Zoned reserve
– Extensive region of land with one or more areas
undisturbed by humans
– Contributes to sustainable development
– Long-term prosperity of human societies and the ecosystems
– Provide an economic base for people living there
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38.12 Zoned reserves are an attempt to reverse
ecosystem disruption
 Zoned reserves are used in Costa Rican conservation
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Nicaragua
Costa
Rica
National parkland
Buffer zone
Pacific Ocean
Caribbean Sea
38.13 CONNECTION: The Yellowstone to Yukon
Conservation Initiative seeks to preserve
biodiversity by connecting protected areas
 Yellowstone to Yukon Conservation Initiative
– Created a string of parks and reserves
– 3,200-km wildlife corridor
– Alaska across Canada to northern Wyoming
– Included introduction of wolf populations
– Sparked angry protests from ranchers
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YUKON
TERRITORY
NORTHWEST TERRITORIES
Whitehorse
ALBERTA
Pacific
Ocean
BRITISH
COLUMBIA
Calgary
Vancouver
MONTANA
Spokane
WASHINGTON
Bozeman
Jackson
OREGON
IDAHO
WYOMING
38.14 CONNECTION: The study of how to restore
degraded habitats is a developing science
 Restoration ecology
– Uses ecological principles to restore environments
 Restoring environments
– Bioremediation
– Using organisms to detoxify polluted ecosystems
– Replanting native vegetation
– Repairing waterways and wetlands
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Lake
Kissimmee
Widened
canal
Water control
structure remaining
Water control
structure removed
River channel
restored
Detail
Atlantic
Ocean
Phase 1
completed
Canal backfilled
Water control
structure to
be removed in
Phase 2
Kissimmee
River
Floodplain
FLORIDA
Gulf of
Mexico
0
Miles
10
Lake
Okeechobee
Former
canal
38.15 Sustainable development is an ultimate goal
 Biosphere is made of complex interconnections
– Sensible decisions needed to conserve these networks
– Must work for a sustainable future
– Sustainable development depends on continued
research and application
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Habitat destruction Invasive species
Overexploitation
Conservation
biology
seeks to conserve
may involve
ecosystems and
landscapes
(a)
may be
protected in
attempt
to restore
nature
reserves
(b)
which uses
restoration
projects
(c)
to
need to identify
and support
may be
detoxify or
replenish degraded
ecosystems
(d)
which support
minimum viable
population size
(e)
sustainable
development
You should now be able to
1. Explain why biodiversity must be protected
2. Describe the three components of biodiversity
3. Explain the major factors that threaten biodiversity
4. Explain the consequences of global climate change
5. Describe major strategies used in conservation
biology
6. Explain the principles of sustainable conservation
practices
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