chapter 22 sustaining wild species chapter 22 sustaining wild species

Chapter 22Sustaining 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 ConceptsKey Concepts

Human effects on biodiversityHuman effects on biodiversity

Importance of biodiversityImportance of biodiversity

How human activities affect wildlifeHow human activities affect wildlife

Management of wildlifeManagement of wildlife

22.1 Human Impacts on Biodiversity

A. Factors that increase biodiversity

Physically diverse habitat Small - moderate

environmental disturbances

Evolution

B. Factors that decrease biodiversity

Environmental stress- *decrease habitats is greatest threat

Large disturbances Extreme conditions Limitation of

essential resources Introduction of alien

species Geographic

Isolation

67%Secure orapparently

secure

1%Other

16%Vulnerable

8%Imperiled

7%Critically imperiled

1% Probably extinct

Fig. 22.4, p. 554

How Serious is a Loss of Biodiversity?

Some argue that the threat is exaggerated…

1. We don’t know how many species there are

2. We don’t know the true value of all species in ecosystems

3. 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 The Ecosystem Approach

Goal

Protect species frompremature 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

Goal

Protect populations ofspecies in their naturalhabitats

Strategy

Preserve sufficient areasof habitats in differentbiomes and aquaticsystems

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 ExtinctionA. 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: PA GAME COMMISSION PA FISH AND BOAT COMMISSION US FISH AN WILDLIFE SERVICE

Rare Species: Naturally small

populations due to limited geographic range

Locally depleted by human activities

Vulnerable to extinction

Characteristic ExamplesLow reproductive rate(K-strategist)

Specialized niche

Narrow distribution

Feeds at high trophic level

Fixed migratory patterns

Rare

Commercially valuable

Large territories

Blue whale, giant panda,rhinocerosBlue whale, giant panda,Everglades kite

Many island species,elephant seal, desert pupfish

Bengal tiger, bald eagle,grizzly bearBlue whale, whooping crane,sea turtlesMany island species,African violet, some orchidsSnow leopard, tiger, elephant, rhinoceros, rare plants and birdsCalifornia 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 Extinction- A rise above the background rate, often catastrophic and global.Estimated to be five in the past 500 million years

Geological Periods

Millions of years ago

Nu

mb

er o

f fa

mil

ies

of

mar

ine

anim

als

Mass extinctions

800

600

400

200

0570 505 438 360 286 208 144 65 0

CambrianOrdovician

SilurianDevonian

Carboniferous

Permian

TriassicJurassic

Cretaceous

TertiaryQuaternary

?

408 245 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. Instrumental Value: Usefulness to humans

2. 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 Intrinsic

Utilitarian Non-utilitarian

(human centered) (species orecosystemcentered)

Goods

Ecological services

Information

Recreation

Existence

Aesthetic

Bequest

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 AsiaTranquilizer, high blood pressure medication

Fig. 22.12a, p. 561

FoxgloveDigitalis purpurea, EuropeDigitalis for heart failure

Fig. 22.12b, p. 561

Pacific yewTaxus brevifolia, Pacific NorthwestOvarian cancer

Fig. 22.12c, p. 561

CinchonaCinchona ledogeriana, South AmericaQuinine for malaria treatment

Fig. 22.12d, p. 561

Rosy periwinkleCathranthus roseus, MadagascarHodgkin's disease, lymphocytic leukemia

Fig. 22.12e, p. 561

Neem treeAzadirachta indica, IndiaTreatment of many Diseases acts as aninsecticide

Fig. 22.12f, p. 561

Overfishing

Habitatloss

Habitatdegradation

Introducingnonnativespecies

Commercialhunting

andpoaching

Sale ofexotic pets

anddecorative

plants

Predatorand

pest control

Pollution

Climatechange

Basic Causes

• Population growth• Rising resource use• No environmental

accounting• Poverty

Fig. 22.13, p. 564

Causes of 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

22.4 CAUSES FOR PREMATURE EXTINCTION

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.

Asian or Indian Elephant

Former range

Range today(34,000–54,000 left)

Fig. 22.14d, p. 565

Indian Tiger

Range 100 years ago

Range today(about 2,300 left)

Fig. 22.14a, p. 565

Black Rhino

Range in 1700

Range today(about 2,400 left)* endangered* Fig. 22.14b, p. 565

African Elephant

Probable range 1600

Range today(600,000 left)

Decline due to habitat loss, legal ivory trade, and poaching

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 fall into two catagories…

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

1918

Fig. 22.18, p. 570

2000

Expansion of the fire ant in southern states.

Formosia termite

Tiger Mosquito- introduced the

West Nile disease

Characteristics ofSuccessful

Invader Species

• High reproductive rate, short generation time (r-selected species)

• Pioneer species

• Long lived

• High dispersal rate

• Release growth- inhibiting chemicals into soil

• Generalists

• High genetic variability

Characteristics ofEcosystems Vulnerable

to Invader Species

• Similar climate to habitat of invader

• Absence of predators on invading species

• Early successional species

• Low diversity of native species

• Absence of fire

• Disturbed by human activities

-Control of Nonnative species begins with identifying characteristics that allow them to succeed

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 InbreedingGenetic Drift Bottleneck Effect

22.5 Solutions to Protecting Species

A. International Treaties

1. CITES (1975 Convention on International Trade in Endangered Species)

800 species that can’t be traded

29,000 species regulated since they are at risk of becoming threatened

LIMITED SUCCESS for CITES

Difficult to enforce Small fines for those

convicted Countries can exempt

themselves Many countries that have not

signed CITES

B. National Laws1. LACEY ACT 1900: Prohibits transport of dead animals

across state lines without a permit2. 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

Concentration of rare species

Low Moderate High

Top Six Hot Spots

1 Hawaii2 San Francisco Bay area3 Southern Appalachians4 Death Valley5 Southern California6 Florida Panhandle

4

5

2

6

3

1 Fig. 22.23, p. 575

6 Hotspots for Endangered Species

Charcoal Roadblock 4min

http://www.youtube.com/watch?v=9cnPljd_jJg&feature=player_embedded

http://www.youtube.com/watch?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 ESAConcerns about the economic impacts…1. Make protection on private land

voluntary2. Have the gov’t pay for lost land3. Make it harder to list new species4. Give the secretary of the interior

the right to allow a species to become extinct

5. Can allow exemptions to states6. Prohibit public lawsuits

Should the ESA be Strengthened?

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

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 ProtectionSafe 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 succeed2. Ones with the greatest

amount of ecological value3. The most useful in medicine* FOCUS ON KEYSTONE

SPECIES

Biome % of Area Disturbed

Temperate broadleaf forests

Temperate evergreen forests

Temperate grasslands

Mixed mountain systems

Tropical dry forests

Subtropical and temperate rain forests

Cold deserts and semidesert

Mixed island systems

Warm deserts and semideserts

Tropical humid forests

Tropical grasslands

Temperate Boreal forests

Tundra

94%

94%

72%

71%

70%

67%

55%

53%

44%

37%

26%

18%

0.7%Fig. 22.15, p. 566

Type of Nonnative Organism Annual Losses and damagesCrop disease

Crop weeds

Rats

Feral cats and outdoor pet cats

Crop insects

Livestock diseases

Forest insects and diseases

Zebra mussels

Common pigeon

Formosan termite

Fishes

Asian clam

Feral pigs

Starlings

Fire ant

$23.5 billion

$23.5 billion

$19 billion

$17 billion

$14 billion

$9 billion

$4.8 billion

$3 billion

$1.1 billion

$1.1 billion

$1.1 billion

$1.1 billion

$0.8 billion

$0.8 billion

$0.6 billionFig. 22.16, p. 566

Estimation of Extinction Risks1. Population Viability Analysis (PVA) Risk assessment with math and

stats2. Minimal Viable Population (MVP) Smallest # of individuals necessary

to ensure the survival of a population

3. Minimum Dynamic Area (MDA) Minimum area of habitat needed to

maintain the MVP