Transcript Chapter 22-Sustaining Wild Speciesx

Chapter 22
Sustaining Wild Species
The Story of Martha
Oh high above the trees and the reeds like rainbows they landed soft as moonglow in greens and reds they
fluttered past the windows ah but nobody cared or saw til the hungry came in crowds with their guns and
dozers and soon the peace was over God what were they thinking of? Oh on and on til dreams come true
you know a piece of us all goes with you Oh the birds went down they fell and they faded to the dozens Til in
a Cincinnati Zoo was the last one Yes all that remained was the last with a name of Martha Very proud, very
sad, but very wise Oh as the lines filed by there were few who cared or could be bothered how could anyone
have treated you harder and it was all for a dollar or more Oh on and on til dreams come true you know a
piece of us all goes with you Oh and surrounded there by some of whom wept around her in a corner of the
cage they found her she went as soft as she came so shy til the last song oh the passenger pigeon was
gone... John Harold
The last word in ignorance is the
person who says of an animal
or plant: “What good is it?...If
the land mechanism as a whole
is good, whether we
understand it or
not…Harmony with land is
like harmony with a friend; you
cannot cherish his right hand
and chop off his left.
Aldo Leopold
Key Concepts
Human effects on biodiversity
Importance of biodiversity
How human activities affect wildlife
Management of wildlife
22.1 Human Impacts on
Biodiversity
A. Factors that increase
biodiversity

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Physically diverse habitat
Small - moderate
environmental
disturbances
Evolution
B. Factors that decrease
biodiversity

Environmental
stress- *decrease
habitats is greatest threat


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Large disturbances
Extreme conditions
Limitation of
essential resources
Introduction of alien
species
Geographic
Isolation
1%
Probably extinct
7%
Critically
imperiled
67%
Secure or
apparently
secure
8%
Imperiled
16%
Vulnerable
1%
Other
Fig. 22.4, p. 554
How Serious is a Loss of
Biodiversity?

1.
2.
3.
Some argue that the threat is
exaggerated…
We don’t know how many
species there are
We don’t know the true value
of all species in ecosystems
Estimates are based on
models that lack data
Should We Focus on Sustaining
Species or Ecosystems?
A. Ecosystem Approach

Major goal is to assure that
there is enough protected
land and water to provide
habitat.
B. Species-by-Species Approach

Identify most at-risk species

Understand the species

Focus on protecting them
C. SANCTUARY APPROACH
- Creation of Refuges
- Gene Banks/Botanical Gardens
- Zoo/Aquariums
* Egg Pulling
* Captive Breeding
The Species Approach
Goal
Protect species from
premature extinction
Strategies
• Identify endangered species
• Protect their critical habitats
Tactics
• Legally protect endangered species
• Manage habitat
• Propagate endangered species in
captivity
• Reintroduce species into suitable
habitats
The Ecosystem Approach
Goal
Protect populations of
species in their natural
habitats
Strategy
Preserve sufficient areas
of habitats in different
biomes and aquatic
systems
Tactics
• 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
22.2 Three Types of Extinction
A. Local Extinction:
Species is no longer found in an area it once
was, but it is found in other areas.
Ex. White tail deer was near a local extinction but has recovered to a
large population size.
*Roosevelt was most
influential in increasing
the White Tailed Deer
population.
B. Ecological Extinction:
 So few that it can no longer
play its ecological role
C. Biological Extinction:



Species is no longer found
anywhere on the earth
Biological Extinction is Forever
Irreversible loss of genes
What are Endangered and
Threatened Species?
Endangered:
 So few individual
survivors that the
species can become
extinct over all or part of
its range
Threatened or Vulnerable:
 Still abundant in its
natural range and may
become endangered
Threatened and Endangered
Species of Pennsylvania Links:

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PA GAME COMMISSION
PA FISH AND BOAT COMMISSION
US FISH AN WILDLIFE SERVICE
Rare Species:

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Naturally small
populations due to
limited geographic
range
Locally depleted by
human activities
Vulnerable to
extinction
Characteristic
Low reproductive rate
(K-strategist)
Specialized niche
Narrow distribution
Feeds at high trophic
level
Fixed migratory patterns
Rare
Commercially valuable
Large territories
Examples
Blue whale, giant panda,
rhinoceros
Blue whale, giant panda,
Everglades kite
Many island species,
elephant seal, desert pupfish
Bengal tiger, bald eagle,
grizzly bear
Blue whale, whooping crane,
sea turtles
Many island species,
African violet, some orchids
Snow leopard, tiger, elephant,
rhinoceros, rare plants and
birds
California condor, grizzly bear,
Florida panther
Background vs. Mass Extinction
Background Extinction-
A small, naturally occurring,
low rate extinction.
Fossil records show 1-14
species a year
(Approximately 1 species /
million) 0.0001% per year
B. Mass ExtinctionA rise above the background rate,
often catastrophic and global.
Estimated to be five in the past 500
million years
Geological Periods
Number of families
of marine animals
Carboniferous
Cretaceous
Devonian
Jurassic
Silurian
Triassic
Tertiary
Ordovician
Permian
Quaternary
Cambrian
800
Mass
extinctions
600
?
400
200
0
570
505
438
360
408
286
208
245
Millions of years ago
144
65
0
2
Fig. 22.10, p. 558
Extinction of the Dinosaurs
22.3 Why Care About Biodiversity?
The Earth’s Overall Biodiversity has 2 Types of
Value:
1.

2.

Instrumental Value:
Usefulness to humans
Intrinsic Value:
Because they exist regardless
of their value
SIDE NOTE

Biologists claim that species have
medical and scientific value,
ecological value, and economic
value.
Value of Nature
Instrumental
(human centered)
Intrinsic
(species or
ecosystem
centered)
Utilitarian
Goods
Ecological services
Non-utilitarian
Existence
Aesthetic
Information
Bequest
Recreation
Fig. 22.11, p.
561
Instrumental Values
Utilitarian (Use)
-Economic goods
-Ecological
Services
-Information
-Recreation
Non-Utilitarian
(Nonuse)
-Existence
-Aesthetic
-Bequest
Rauvolfia
Rauvolfia sepentina,
Southeast Asia
Tranquilizer, high
blood pressure
medication
Fig. 22.12a, p. 561
Foxglove
Digitalis purpurea,
Europe
Digitalis for heart failure
Fig. 22.12b, p. 561
Pacific yew
Taxus brevifolia,
Pacific Northwest
Ovarian cancer
Fig. 22.12c, p. 561
Cinchona
Cinchonaledogeriana,
South America
Quinine for malaria
treatment
Fig. 22.12d, p. 561
Rosy periwinkle
Cathranthus roseus,
Madagascar
Hodgkin's disease,
lymphocytic leukemia
Fig. 22.12e, p. 561
Neem tree
Azadirachta indica,
India
Treatment of many
Diseases acts as an
insecticide
Fig. 22.12f, p. 561
Habitat
loss
Causes of Premature
Extinction
Overfishing
Habitat
degradation
Basic Causes
Climate
change
• Population growth
• Rising resource use
• No environmental
accounting
• Poverty
Introducing
nonnative
species
Commercial
hunting
and
poaching
Pollution
Predator
and
pest control
Sale of
exotic pets
and
decorative
plants
Fig. 22.13, p. 564
22.4 CAUSES FOR
PREMATURE EXTINCTION
A. Habitat loss and degradation
-Greatest threat to wild species
-In U.S. the major disturbances
are…
*agriculture
*development
*outdoor recreation
*grazing
*pollution
Habitat Fragmentation
–A large, continuous area of habitat
is reduced in area and divided into a
patchwork of isolated areas.
Can result in loss of genetic
diversity, create barriers, create
limited habitats.
Former range
Range today
(34,000–54,000 left)
Asian or Indian Elephant
Fig. 22.14d, p. 565
Range 100 years ago
Range today
(about 2,300 left)
Fig. 22.14a, p. 565
Indian Tiger
Range in 1700
Range today
(about 2,400 left)
* endangered*
Black Rhino
Fig. 22.14b, p. 565
Decline due to habitat loss,
legal ivory trade, and
poaching
Probable range 1600
Range today
(600,000 left)
African Elephant
2. Harm by Nonnative Species
-U.S. has 50,000 Nonnative species
-49% of 1,200 endangered and threatened
species are threatened by nonnative species.
**Can decrease biodiversity.
-Nonnative species
catagories…
fall into two
A. Deliberately Introduced
B. Accidentally Introduced
A. Deliberately Introduced
-Supply 98% of U.S. food

-Can have detrimental affects w/no predators,
parasites, or competition to control numbers.
Example: Asian Carp
KUDZU VINE:
B. Accidentally Introduced
Many times they are transported
in shipping products
Expansion of
the fire ant in
southern
states.
1918
2000
Fig. 22.18, p. 570
Tiger Mosquitointroduced the
West Nile disease
Formosia termite
-Control of Nonnative species begins with
identifying characteristics that allow them to
succeed
Characteristics of
Successful
Invader Species
• High reproductive
rate, short
generation time (rselected species)
• Pioneer species
• Long lived
Characteristics of
Ecosystems Vulnerable
to Invader Species
• Similar climate to
habitat of invader
• Absence of predators
on invading species
• Early successional
species
• High dispersal rate
• Release growthinhibiting chemicals
into soil
• Generalists
• High genetic
variability
• Low diversity of
native species
• Absence of fire
• Disturbed by human
activities

3. Commercial Hunting/Poaching
-International trade of wild plant and
animals is worth $10-$20 billion dollars
per year.
-1/4 of total is in illegal sales.
Animals worth more if made an attraction for Ecotourism.
Gorilla - $150,000
 Chimp - $50,000
 Rhino Horn - $13,000/lb.
 Bushmeat - $150 million /yr.

Fig. 22.24, p. 576
This family of Gorillas was
Slaughtered for Bush meat
Orphans of the Slaughter
Gorilla Hand: A Delicacy
Poachers Use a Chain Saw to Remove a
Rhino Horn
POACHING A EGG
Ivory Trade
Profiting from Safaris 5min flash
A Controversial Management
Practice “Culling” 5min flash
4. Exotic Pets
-25 Million U.S. households have exotic birds
-Leads to a loss of Ecotourism
-Use of Cyanide to capture tropical fish
-Orchids and Cacti for decoration
* The pet trade has depleted populations of
birds, tropical fish, and mammals
Using Chemicals to catch
exotic fish 3min flash
5. Climate Change and Pollution
-Increase in global warming
-Introduction of pesticides/herbicides,
etc.
6. Loss of Genetic Diversity
-Decreased ability to reproduce and adapt
to changing conditions
Founder Effect
Genetic Drift
Inbreeding
Bottleneck Effect
22.5 Solutions to Protecting
Species
A.
International Treaties
1. CITES (1975 Convention on
International Trade in
Endangered Species)

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800 species that can’t be traded
29,000 species regulated since
they are at risk of becoming
threatened
LIMITED SUCCESS for CITES

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Difficult to enforce
Small fines for those
convicted
Countries can exempt
themselves
Many countries that have not
signed CITES
B. National Laws
1.
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2.
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LACEY ACT 1900:
Prohibits transport of dead animals
across state lines without a permit
ENDANGERED SPECIES ACT: *Most
species on listed on ESA have not
recovered.
Illegal to import or trade any product
from an endangered or threatened
species…
Unless used for scientific purposes
* 1st organism to be listed on ESA due to
global climate change = Polar Bear
Who Determines What is
Protected?
National Marine Fisheries Service:
List and identify Ocean Species

U.S. Fish and Wildlife Service:
Identify all other endangered
species. Also regulates the
enforcement of the ESA and CITIES
Treaty

* Fines and imprisonment can be imposed to
ensure the protection of endangered species
6 Hotspots for
Endangered Species
2
4
3
5
Top Six Hot Spots
6
1 Hawaii
2 San Francisco Bay area
3 Southern Appalachians
4 Death Valley
5 Southern California
6 Florida Panhandle
Concentration of rare species
1
Low
Moderate
High
Fig. 22.23, p. 575
Charcoal Roadblock 4min
http://www.youtube.com/watch?v=9cnPlj
d_jJg&feature=player_embedded
http://www.youtube.com/wat
ch?v=tJ5nfgYJhD4
What Have Land Owners Done
to Avoid the ESA?


Some land
owners have
managed their
land so less
endangered
species use it
*The Bald Eagle was the
first organism to be
protected under the ESA
Should We Weaken the ESA
Concerns about the economic impacts…
1. Make protection on private land
voluntary
2. Have the gov’t pay for lost land
3. Make it harder to list new species
4. Give the secretary of the interior
the right to allow a species to
become extinct
5. Can allow exemptions to states
6. Prohibit public lawsuits
Should the ESA be Strengthened?

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0.05% of projects have been
blocked by ESA
The act does allow for
economic concerns
“God Squad” – any federal
project can be exempted
from ESA to prevent
economic loss
Government will bargain with
HCP’s
Habitat Conservation Plans (HCP)
Used as a compromise between
the interests of land owners and
the threatened species
 Owners are allowed to destroy
some habitat or endangered
species on private land…
 In exchange for taking
measures to protect the species

Protective Measures of HCP’s

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Set aside a part of the habitat
as a preserve
Pay to relocate to a suitable
habitat
Pay the government to buy
suitable habitat elsewhere.
What are the concerns with this type
of plan?
Removing Barriers of Protection
Safe Harbor Agreement:
 Land owners voluntarily
restore habitat on their land
Candidate Conservation
Agreement:
 Landowners volunteer to take
steps to help declining
populations not yet listed
Should We Try to Protect all
Species?
Can’t possibly save all
 Focus on…
1. Most likely to succeed
2. Ones with the greatest
amount of ecological value
3. The most useful in medicine
* FOCUS ON KEYSTONE
SPECIES

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 semidesert
55%
Mixed island systems
53%
Warm deserts and
semideserts
44%
Tropical humid forests
37%
Tropical grasslands
26%
Temperate Boreal forests
18%
Fig. 22.15, p. 566
Tundra
0.7%
Type of Nonnative Organism
Crop disease
Annual Losses and damages
$23.5 billion
Crop weeds
$23.5 billion
Rats
$19 billion
Feral cats and outdoor pet cats
$17 billion
Crop insects
Livestock diseases
Forest insects and diseases
$14 billion
$9 billion
$4.8 billion
Zebra mussels
$3 billion
Common pigeon
$1.1 billion
Formosan termite
$1.1 billion
Fishes
$1.1 billion
Asian clam
$1.1 billion
Feral pigs
$0.8 billion
Starlings
$0.8 billion
Fire ant
$0.6 billion
Fig. 22.16, p. 566
Estimation of Extinction Risks
1.

2.

3.

Population Viability Analysis (PVA)
Risk assessment with math and
stats
Minimal Viable Population (MVP)
Smallest # of individuals necessary
to ensure the survival of a
population
Minimum Dynamic Area (MDA)
Minimum area of habitat needed to
maintain the MVP