Chapter 9
Sustaining Biodiversity:
The Species Approach
REVIEW
Extreme tropical deforestation in Chiang Mai,Thailand.
What do you think will happen to the dried out topsoil when the winds come?
How does the term ecological tipping point apply here?
Fig. 9-9, p. 184
Questions for Today:





What are the three types of extinctions?
What are the differences between endangered and
threatened species?
What are characteristics that make species
vulnerable to extinctions?
Where can you find the latest Endangered Species
List and How do scientists classify endangered
animals?
How do scientists catalogue and predict
extinctions?
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 overharvest and habitat
loss.
Figure 11-1
Extinctions - Human Impact

Some human activities are causing extinctions
 Disturbance



Filling in wetlands
Converting grasslands and forests to crop fields and
urban areas
Pollution of surface water
“The natural world is everywhere disappearing
before our eyes-cut to pieces, mowed down,
plowed under, gobbled up, replaced by human
artifacts.” – Edward O. Wilson
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
Passenger pigeon
Great auk
Dodo
Dusky seaside
sparrow
Aepyornis
(Madagascar)
Fig. 11-2, p. 223
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
Percentage of Various Species
Threatened with Premature Extinction
Fig. 11-3, p. 224
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
SPECIES
EXTINCTION
 Some
species
have
characteristics
that make them
vulnerable to
ecological and
biological
extinction.
Figure 11-4
Endangered Species
 As
biodiversity expert Edward O. Wilson said,
“The first animal species to go are the big, the
slow, the tasty, and the those with valuable
parts such as tusks and skins.”
 Some have behavioral characteristics such
as the passenger pigeon that nests in large
flocks and the Key Deer
which are “nicotine addicts”.
They come out by the roads to
search for cigarette butts.
SPECIES EXTINCTION
 Scientists
use measurements and models to
estimate extinction rates.



The International Union for the Conservation of
Nature and Natural Resources (IUCN) publishes
an annual Red List, listing the world’s threatened
species.
The 2004 Red List contains 15,589 species at
risk for extinction.
Examine the Red List yourself at:
www.iucnredlist.org
Figure 11-5
SPECIES EXTINCTION
Three major problems in cataloging
extinctions:

1.
2.
3.
The extinction of a species typically takes such
a long time, so it’s not easy to document.
There are many species (approx. 100 Million
Species) and we have only classified 1.9
million.
Scientists know little about the nature and
ecological roles of species that have been
identified.
Extinction Rates
 Remember:

In due time, all species become extinct.
 Before
Humans arrived on earth the
estimated extinction rate was roughly
0.0001% per year.

The current rate is roughly between 0.01% to 1%
• Conservative estimate
On a Monument to a Pigeon
Read
with group.
What is the main idea or theme?
What are the key points?
List 3 WOW factors
Questions for Today
 Why
should we care about Wild Species?
 What are some ecological and economical
services wild species have?
 What is HIPPCO?
 What are Invasive Species?
 What are characteristics of a Good Invasive
Species?
IMPORTANCE OF WILD SPECIES
 We
should not cause the premature
extinction of species because of the
economic and ecological services they
provide.
 Some believe that each wild species has an
inherent right to exist.

Some people distinguish between the survival
rights among various types of species (plants vs.
animals).
Importance of Wild Species
 Types
of Ecological and Economic Services
that Wild Species have:

Instrumental Value – food, fuelwood, lumber,
paper, and medicine
• 62% of all cancer drugs were created by
bioprospecting (Scientific research that looks for a
useful application, process, or product in nature).

Genetic Information – cannot evolve without new
and novel traits found in species.
• Careless elimination of genes is like burning books
before reading them.
Importance of Wild Species
 Recreational



Pleasure
Each year, Americans spend three times as
many hours watching wildlife, as they spend
watching movies or sports events.
Ecotourism generates $500 BILLION per year
worldwide.
A 7 year old male lion living to the age of 7
generates 515,000 (73,571 dollars a year) dollars
for Kenya.
• It’s pelt is only worth 1000 dollars.
HABITAT LOSS, DEGRADATION,
AND FRAGMENTATION
 Conservation
biologists summarize the most
important causes of premature extinction as
“HIPPCO”:






Habitat destruction, degradation, and
fragmentation
Invasive species
Population growth
Pollution
Climate Change
Overharvest
What are Invasive Species?
 Invasive

Species:
Species introduced by man, deliberately or
accidentally, into a local ecosystem where the
new species has caused a dramatic change in
the roles of other species within the original
ecosystem.
• Biggest cause of animal and plant extinctions
• About 50,000 nonnative species now live in the US
and about 1 and 7 of them are harmful
• Also called Biotic Pollution.
INVASIVE SPECIES
 Many
Kudzu vine was introduced in
the southeastern U.S. to
control erosion. It has taken
over native species habitats.
nonnative
species provide us
with food, medicine,
and other benefits
but a a few can wipe
out native species,
disrupt ecosystems,
and cause large
economic losses.
Figure 11-A
INVASIVE SPECIES
 Many
invasive species have been introduced
intentionally.
Figure 11-11
Deliberately Introduced Species
Purple loosestrife European starling African honeybee
(“Killer bee”)
Marine toad
(Giant toad)
Water hyacinth
Japanese
beetle
Nutria
Hydrilla
Salt cedar
(Tamarisk)
European wild boar
(Feral pig)
Fig. 11-11a, p. 234
INVASIVE SPECIES
 Many
invasive species have been introduced
unintentionally.
Figure 11-11
Accidentally Introduced Species
Sea lamprey
Argentina
(attached to lake trout) fire ant
Formosan termite
Zebra mussel
Brown tree
snake
Asian longhorned beetle
Eurasian ruffe
Asian tiger
mosquito
Common pigeon
(Rock dove)
Gypsy moth larvae
Fig. 11-11b, p. 234
Fig. 11-11, p. 234
INVASIVE SPECIES
 The
Argentina fire
ant was introduced
to Mobile, Alabama
in 1932 from South
America.


Most probably from
ships.
No natural
predators.
Figure 11-12
INVASIVE
SPECIES
 Prevention
is the
best way to reduce
threats from
invasive species,
because once they
arrive it is almost
impossible to slow
their spread.
Figure 11-13
What Can You Do?
Invasive Species
• Do not allow wild animals to escape.
• Do not spread wild plants to other areas.
• Do not dump the contents of an aquarium into waterways,
wetlands, or storm drains.
• When camping use wood near your campsite instead of bringing
firewood from somewhere else.
• Do not dump unused bait into the water.
• After dogs visit woods or the water brush them
them home.
before taking
• After each use clean your vehicle, mountain bike, surfboard,
kayaks, canoes, boats, tent, hiking boots, and other gear before
heading for home.
• Empty all water from canoes, kayaks, dive gear, and other
outdoor equipment before heading home.
• Plant a variety of trees, shrubs, and other plants in your yard to
reduce losses from invasive species.
• Do not buy plants from overseas or swap them with others using
the Internet.
Fig. 11-14, p. 236
Characteristics of
Successful
Invader Species
• High reproductive rate,
short generation time
(r-selected species)
• Pioneer species
• Long lived
Characteristics of
Ecosystems Vulnerable
to Invader Species
• Climate similar to
habitat of invader
• Absence of predators
on invading species
• Early successional
systems
• High dispersal rate
• Release growth-inhibiting
chemicals into soil
• Low diversity of
native species
• Absence of fire
• Generalists
• High genetic variability
• Disturbed by human
activities
Fig. 11-13, p. 236
Questions for Today
 How
has pollution, population growth and
overexploitation lowered Species
Biodiversity?
 What are the two major laws that protect
species on our planet?
POPULATION GROWTH,
POLLUTION, AND CLIMATE
CHANGE
 Population
growth, affluenza, and pollution
have promoted the premature extinction of
some species.
 Projected climate change threatens a number
of species with premature extinction.
 Affluenza

a painful, contagious, socially transmitted
condition of overload, debt, anxiety and waste
resulting from the dogged pursuit of more
Pollution
 Each




Example of biomagnification
of DDT in an aquatic food
chain.
year pesticides:
Kill about 1/5th of the
U.S. honeybee
colonies.
67 million birds.
6 -14 million fish.
Threaten 1/5th of the
U.S.’s endangered
and threatened
species.
Figure 11-15
OVEREXPLOITATION
 Some
protected species are killed for their
valuable parts or are sold live to collectors.
 Killing predators and pests that bother us or
cause economic losses threatens some
species with premature extinction.
 Legal and illegal trade in wildlife species
used as pets or for decorative purposes
threatens some species with extinction.
OVEREXPLOITATION
 Rhinoceros
are often
killed for their horns
and sold illegally on
the black market for
decorative and
medicinal purposes.
Figure 11-16
Case Study:
Rising Demand for Bushmeat in
Africa
 Bushmeat
hunting has
caused the local
extinction of
many animals in
West Africa.
 Can spread
disease such as
HIV/AIDS and
ebola virus.
Figure 11-17
PROTECTING WILD SPECIES: LEGAL
AND ECONOMIC APPROACHES
 International
treaties have helped reduce the
international trade of endangered and
threatened species, but enforcement is difficult.
 CITES - Its aim is to ensure that international
trade in specimens of wild animals and plants
does not threaten their survival.

One of the most powerful is the 1975 Convention on
International Trade of Endangered Species (CITES
).
• Signed by 169 countries, lists 900 species that cannot be
commercially traded.
Case Study:
The U.S. Endangered Species Act
 One
of the world’s most far-reaching and
controversial environmental laws is the 1973
U.S. Endangered Species Act (ESA).


ESA forbids federal agencies (besides defense
department) to carry out / fund projects that
would jeopardize an endangered species.
ESA makes it illegal for Americans to engage in
commerce associated with or hunt / kill / collect
endangered or threatened species.
Case Study:
The U.S. Endangered Species Act
 Biodiversity
hotspots in relation to the largest
concentrations of rare and potentially
endangered species in the U.S.
Figure 11-18
Top Six Hot Spots
1 Hawaii
2 San Francisco Bay
area
3 Southern
Appalachians
4 Death Valley
5 Southern California
6 Florida Panhandle
Concentration of rare species
Low
Moderate
High
Fig. 11-18, p. 241
Endangered Species
 Because
of
scarcity of
inspectors,
probably no
more than 1/10th
of the illegal
wildlife trade in
the U.S. is
discovered.
Figure 11-19
Endangered Species
 Congress
has amended the ESA to help
landowners protect species on their land.
 Some believe that the ESA should be
weakened or repealed while others believe it
should be strengthened and modified to focus
on protecting ecosystems.
 Many scientists believe that we should focus
on protecting and sustaining biodiversity and
ecosystem function as the best way to
protect species.
What Can You Do?
Protecting Species
• Do not buy furs, ivory products, and other
materials made from endangered or threatened
animal species.
• Do not buy wood and paper products
produced by cutting remaining oldgrowth forests in the tropics.
• Do not buy birds, snakes, turtles, tropical fish,
and other animals that are taken from the wild.
• Do not buy orchids, cacti, and other plants that
are taken from the wild.
• Spread the word. Talk to your friends and
relatives about this problem and what they can
do about it.
Fig. 11-21, p. 246
How do I know?
The first place to look is at the label at the end of the ream, which will show a variety of symbols. A
typical ream label might look something like this:
Paper real label
Notice the symbols in the middle of
the label? These are examples of
the three types of symbols to look for:
* Green Certification Programs
* Recycled content
* Chlorine use
The Forest Stewardship Council certifies the paper came from sustainably harvested forests.
Green Seal certifies many green products, including paper.
Environmental Choice is a Canadian government environmental certification
Endangered and Threatened
Species
In Texas:
http://www.tpwd.state.tx.us/huntwild/wild/species/endang/
State Status Federal Status (Listed)
Loggerhead Sea Turtle - Threatened
Green Sea Turtle - Threatened
Atlantic Hawksbill Sea Turtle - Endangered
Mexican Long-nosed bat – Endangered
Whooping Crane – Endangered
Bald Eagle – Threatened
Red-cockaded Woodpecker - Endangered
Endangered Species
Spiny-flanked Chameleon
Kirtland’s Warbler
Siau Island Tarsier
Atlantic Sturgeon
Wood Turtle