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Chapter 18
Conservation of Biodiversity
How do coral reefs form?
Core Case Study: Why Should
We Care about Coral Reefs? (1)
• Biodiversity
• Formation
• Important ecological and economic services
–
–
–
–
–
–
Moderate atmospheric temperatures
Act as natural barriers protecting coasts from erosion
Provide habitats
Support fishing and tourism businesses
Provide jobs and building materials
Studied and enjoyed
Core Case Study: Why Should
We Care about Coral Reefs? (2)
• Degradation and decline
– Coastal development
– Pollution
– Overfishing
– Warmer ocean temperatures leading to coral
bleaching
– Increasing ocean acidity
The 6th Mass Extinction

Extinction- when there are no longer any of the
species in the world.

We are currently losing approximately 50,000
species per year.
Genetic Diversity


Scientists want to conserve genetic diversity so
that the species can survive environmental
change and inbreeding will not occur.
Inbreeding occurs when individuals with similar
genotypes, generally relatives, breed with each
other.
Categories of Endangerment




Extinct- no known species exist today
Threatened- species with a high risk of
extinction in the future
Near-threatened- species that are likely to
become threatened in the future
Least concern- species are widespread and
abundant
Core Case Study:
The Passenger Pigeon - Gone Forever
• Once the most numerous
bird on earth.
• In 1858, Passenger Pigeon
hunting became a big
business.
• By 1900 they became
extinct from over-harvest
and habitat loss.
Figure 11-1
SPECIES EXTINCTION
• Species can become extinct:
– Locally: A species 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.
– Globally (biologically): Species is no longer found
on the earth.
Global Extinction
• Some animals have become prematurely extinct
because of human activities.
Figure 11-2
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.
Figure 11-3
Grizzly bear
Utah prairie dog
Kirkland’s
warbler
Knowlton
cactus
Florida
manatee
Swallowtail
butterfly
Humpback
chub
Golden lion
tamarin
African elephant
Siberian tiger
Fig. 11-3, p. 224
Giant panda Black-footed Whooping
crane
ferret
Mountain gorilla Florida
panther
California
condor
Northern
spotted owl
Hawksbill
sea turtle
Blue whale
Black
rhinoceros
Fig. 11-3, p. 224
HIPCO
H- Habitat Loss
 I- Invasive Species
 P- Pollution
 C- Climate Change
 O- Overharvested

Habitat Loss


For most species the greatest cause of decline and
extinction is habitat loss.
Most habitat loss is due to human development
Invasive Species



Alien species (exotic species)- species that live
outside their historical range.
Invasive species- when alien species spread
rapidly across large areas.
E.g.- Kudzu Vine, Zebra Mussel, Silver Carp
INVASIVE SPECIES
• Many invasive species have been introduced
intentionally.
Figure 11-11
INVASIVE SPECIES
• Many invasive species have been introduced
unintentionally.
Figure 11-11
Pollution

Threats to biodiversity can come from toxic
contaminants such as pesticides, heavy metals,
acids, and oil spills.
Climate Change

The concern is how climate change will affect
temperature and precipitation around the world,
and how this will impact biodiversity.
Overharvesting


When individuals of a species are removed at a rate
faster than the population can replace them.
Ex- dodo, American bison, passenger pigeon.
Lacey Act
One of the earliest laws in the U.S. to control
the trade of wildlife.
 First passed in 1900, the act prohibited the
transport of illegally harvested game animals,
primarily birds and mammals, across state
lines.

CITES



Convention on International Trade in
Endangered Species of Wild Fauna and Flora
Developed in 1973 to control the international
trade of threatened plants and animals.
Today, CITES is an international agreement
between 175 countries of the world.
Red List


The IUCN keeps a list of threatened species,
known as the red list.
Each country has its own way to monitor and
regulate the import and export of animals on the
list.
Conservation Legislation

Marine Mammal Protection Act- prohibits the
killing of all marine mammals in the U.S. and
prohibits the import or export of any marine
mammal body parts.
Endangered Species Act



Endangered Species Act- first passed in 1973, it
authorizes the U.S. Fish and Wildlife Service to
determine which species can be listed as
threatened or endangered and prohibits the
harming of these species.
Trading these species is also illegal.
The act also authorizes the government to
purchase habitat that is critical to the species.
Regulatory Takings
• Eminent Domain requires compensation for
loss of value of land
• Restriction on development of land because of
protection of habitat for endangered species
also results in loss of value
• Takings legislation is intended to compensate
land owner for future loss of earnings
Convention on Biological
Diversity


In 1992, nations came together and made a treaty
to protect biodiversity.
The treaty had three objectives: conserve
biodiversity, sustainably use biodiversity, and
equitably share the benefits that emerge from
the commercial use of genetic resources such as
pharmaceutical drugs.
Size, Shape and Connectedness


When designing and managing protected areas
we must consider how close to another area they
should be, how large the area is, and the amount
of edge habitat the area contains.
Edge habitat- the area where two different
communities come together, typically forming
an abrupt transition. Ex. A grassy field meeting
a forest.
Theory of Island Biogeography
• Applies to “islands” of habitat
• Given limited funding and limited
undeveloped area, would one large parcel or
several small ones be preferable for
maintaining a population?
• Considerations
– Edge habitat
– Metapopulations?
Biosphere Reserves

Protected
areas
consisting of
zones that
vary in the
amount of
permissible
human
impact.
NATURE RESERVES
• Large and medium-sized reserves with buffer
zones help protect biodiversity and can be
connected by corridors.
 Costa
Rica has
consolidated its parks
and reserves into 8
megareserves
designed to sustain
80% if its biodiversity.
Figure 10-10B
Debt for Nature Swaps
• Debtor nations may pay off their loans with
payments to environmental organizations
• Payments may be used to purchase land, pay
rangers to protect from poaching and illegal
logging, pay for population studies
• Program is in place with Guatemala
• Debt probably wouldn’t be repaid anyway
– Win-Win