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Copyright © 2009 Pearson Education, Inc.
PowerPoint Lectures for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
Chapter 38 Conservation Biology
Lecture by Brian R. Shmaefsky
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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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Scientists are concerned about the ecological changes that underlie biodiversity loss
– Ecologists point out the “services” provided by the biodiversity of ecosystems
38.1 Biodiversity is a vital resource that is being lost
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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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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
38.2 Biodiversity includes genetic, species, and ecosystem diversity
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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
38.2 Biodiversity includes genetic, species, and ecosystem diversity
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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Invasive species rank behind habitat destruction as a threat to biodiversity
Invasive species
– Compete with native species
– Prey on native species
– Parasitize native species
38.3 Habitat destruction, invasive species, and overexploitation are major threats to biodiversity
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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
38.3 Habitat destruction, invasive species, and overexploitation are major threats to biodiversity
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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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Pollutants in a food chain can lead to biological magnification
38.4 CONNECTION: Pollution of the environment compounds our impact on other species
Concentrationof PCBs
Herringgull eggs124 ppm
Lake trout4.83 ppm
Smelt1.04 ppm
Zooplankton0.123 ppm
Phytoplankton0.025 ppm
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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
–2 –1.6 –1.2 –.8 –.4 –.2 .2 .4 .8 1.61.2 2.1
200519811938
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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
15001000 2000
Year
1000
2000
1800
1600
1400
1200
800
600
5000
250
400
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Carbon Dioxide (CO2)
Methane (CH4)
Nitrous Oxide (N2O)
CO
2(p
pm
), N
2O
(p
pb
)
CH
4(p
pb
)
Atmosphere
Ocean
Photosynthesis
Fossilfuel
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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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Red squirrels in Canada
– Natural selection to coordinate breeding time with food availability
38.8 EVOLUTION CONNECTION: Global climate change is an agent of natural selection
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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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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
38.9 Protecting endangered populations is one goal of conservation biology
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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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Edges can fragment ecosystems
Fragmentation is corrected with movement corridors
38.10 Sustaining ecosystems and landscapes is a conservation priority
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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
Equator
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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
38.11 Protected areas are established to slow the loss of biodiversity
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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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Zoned reserves are used in Costa Rican conservation
38.12 Zoned reserves are an attempt to reverse ecosystem disruption
National parkland
Buffer zone
Pacific Ocean
Caribbean SeaNicaragua
CostaRica
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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
NORTHWEST TERRITORIES
ALBERTA
YUKONTERRITORY
BRITISHCOLUMBIA
MONTANA
WASHINGTON
OREGON
IDAHOWYOMING
Jackson
Bozeman
Spokane
Calgary
Vancouver
PacificOcean
Whitehorse
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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
Widenedcanal
Water controlstructure remaining
LakeKissimmee
Kissimmee
River
Floodplain
Lake
Okeechobee
Atlantic
Ocean
Gulf of
Mexico
FLORIDA
Detail
Miles
0 10
Water control
structure removed
River channelrestored
Canal backfilled
Phase 1completed
Water control
structure to
be removed in
Phase 2
Formercanal
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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
Habitat destruction Invasive species Overexploitation
Conservation
biology
may involveseeks to conserve
ecosystems and
landscapes
attemptto restore
may be
protected inwhich uses
nature
reserves
restoration
projects
may beneed to identify
and support detoxify or
replenish degraded
ecosystems
to
sustainable
development
which support
(e)minimum viable
population size
(d)
(c)
(b)(a)
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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