In Class Assignment BiomesName:___________________

• ____________ contains widely scattered clumps of trees such as acacia which are covered with thorns, has warm temps year round, and alternating wet and dry seasons

• _____________humans have converted much of this biome to farmland because its fertile soil is good for raising crops and grazing cattle

• ______________ in this biome very little plant litter reaches the ground, nutrients that do reach the ground are soon leached from soil by constant rainfall, and 90% of plant nutrients released by decomposition are taken up and stored by plants

• _______________ contain majority of world’s forests, host many endemic species, key in hydrologic cycle.

• Coral is formed by ______________ . They are in a symbiotic relationship with __________________ algae.

• ____________________ coastal forests with extensive root systems that often extend above the water. Can be found on some tropical coastlines.

ENVIRONMENTAL SCIENCE 13eCHAPTER 8:Sustaining Biodiversity: The Species Approach

“In the end we will conserve only what we love. We love only what we understand. We will understand only what we are taught.” Baba Dioum

Fig. 8-1, p. 152

Core Case Study: Polar Bears and Projected Climate ChangeIn Chapter 7 we discussed climate and biomes. What affect do you think climate change will have on arctic biomes?

Polar bear video

• http://www.youtube.com/watch?v=OwZH_aT0FGI&feature=related

Core Case Study: Polar Bears and Projected Climate Change

• 20,000 – 25,000 polar bears in Arctic

• Hunt seals on winter sea ice• Global warming is quickly reducing the

amount of sea ice and how long it lasts in winter

• Polar bears have less time to hunt and store fat for summer fasting

Polar Bear Case Study

• Projected 30-35% decline of total polar bear population by 2050

• Potentially extinct from wild by 2100

Resource: San Diego Zoo Website

• http://www.sandiegozoo.org/polarcam/gallery.html

• http://blogs.sandiegozoo.org/category/default/polar-bears/

San Diego Zoo Global is an international conservation organization that has been saving species for over 95 years. Experts in scientifically based breeding, conservation, and reintroduction programs for endangered species.

What do you think

• How have human activities affected natural extinction rates?

• How are we likely to affect such rates in the next 50-100 years?

8-1 What Role Do Humans Play in the Premature Extinction of Species?

• Concept 8-1 Species are becoming extinct 100 to 1,000 times faster than they were before modern humans arrived on earth, and by the end of this century, the extinction rate is expected be 10,000 times higher than the background rate.

Human Activities and Extinction

• Background extinction rate- normal extinction of various species as a result of various changes in local environmental conditions

• Current rate is 100-1,000 times background extinction

• Rate likely to rise to 10,000 times• Is a mass extinction coming?• Mass extinction- catastrophic, widespread often global

event in which major groups of species are wiped out over a short time compared with normal (background) extinctions

Review of terms

• Local extinction-

• Biological extinction-

Review of terms

• Local extinction- species is no longer found in one area it once inhabited but is found in other areas but is found elsewhere on earth

• Biological extinction- species is no longer found anywhere on earth; biological extinction is forever! Irreversible

Current Extinction Rate Estimates Are Conservative

• Rate of species loss and biodiversity losses will increase in next 50–100 years

• Why?

• Biodiversity hotspot rates higher than global average

• We are eliminating, degrading, fragmenting and simplifying many biologically diverse environments that would serve as the sites for the emergence of new species

Fig. 8-2, p. 154

Some animal species that have become prematurely extinct largely because of human activities, mostly habitat destruction and overhunting.

What are endangered and threatened species?

• Endangered species: wild species with so few individual survivors that the species could soon become extinct in all or most of it’s natural range

• Threatened species-wild species that is still abundant in its natural range but is likely to become endangered in the near future because of a decline in numbers

• • Edward O Wilson “The first animal species to go are the big, the

slow, the tasty, and those with valuable parts such as tusks and skins”

• Some behaviors make species prone to extinction: ex. Passenger pigeon, Key deer

Large territories

Blue whale, giant panda, rhinoceros

Blue whale, giant panda, Everglades kite

Elephant seal, desert pupfish

Bengal tiger, bald eagle, grizzly bear

Blue whale, whooping crane, sea turtle

African violet, someorchids

Snow leopard, tiger, elephant, rhinoceros, rare plants and birds

California condor, grizzly bear, Florida panther

ExamplesCharacteristic

Low reproductiverate

Specializedniche

Narrowdistribution

Feeds at hightrophic level

Fixed migratorypatterns

Rare

Commerciallyvaluable

Fig. 8-4, p. 157

Characteristics ofspecies that are prone to ecological and biological extinction.

Critical Thinking

Which of these characteristics might contribute to the premature extinction of the polar bear during this century?

Case Study:Passenger Pigeon: Gone Forever

• John James Audubon, 1813: took 3 days for a flock to pass over, flock so dense it darkened the skies

• Yet by 1900, North America’s Passenger Pigeon, once one of the most abundant birds on earth, was extinct

– Good to eat– Feathers good for pillows– Bones good for fertilizer– Easy to kill, flew in flocks and nested in

colonies

Passenger Pigeon links

• http://mnh.si.edu/onehundredyears/featured_objects/martha2.html

• First link has short video clip• http://blogs.smithsonianmag.com/aroundthemall/2011/09/martha-the-

worlds-last-passenger-pigeon/

Cincinnati Zoo Memorial to Martha and the Passenger Pigeons

Critical Thinking: What difference does it make that the passenger pigeon is extinct?

Considerations

• Intrinsic (existence) value: each wild species has inherent right to exist regardless of its usefulnes to us

• Stewardship viewpoint: we have an ethical responsibility to protect species from becoming prematurely extinct as a result of human activities and to prevent the degradation of the world’s ecosystems and its overall biodiversity

• Instrumental value: species usefulness to us because of the many ecological and economic services they help provide as part of the earth’s natural capital

8-2 Why Should We Care about Preventing Species Extinction? • Concept 8-2 We should prevent the

premature extinction of wild species because of

the economic and ecological services they provide

and because they have a right to exist regardless of their usefulness to us.

Value of Species

• Instrumental value of BIODIVERSITY – Food crops– Genetic information– Medicine– Bioprospectors– Ecotourism

• We do not know what we lose when species go extinct

Critically Endangered

• According to the WWF, the 5 most endangered animals in the wild are the Javan rhino (70 left), whooping crane (250 left), mountain gorilla (600 left), Siberian tiger (700 left), and the California condor (336 left)

• I was fortunate to learn more about the California condors last year when I went to San Diego and visited the San Diego Zoo and the San Diego Zoo Safari Park (Wild Animal Park)

San Diego Zoo Global

International conservation organization that has been saving species for over 95 years

Experts in scientifically based breeding, conservation, and reintroduction programs for endangered species

Case Study: Trying to Save the California Condor

• Nearly extinct with only 22 condors remaining in the wild

• Last 22 individuals captured, bred in captivity

• Released a few at a time

• 2009: 167 condors in the wild

• Greatly threatened by lead poisoning from animal carcasses and gut piles

Total World Population of California Condors

Condor Population reaches 100 in California

The goal of the California Condor Recovery Plan is to establish two geographically separate populations, one in California and the other in Arizona, each with 150 birds and at least 15 breeding pairs. As the Recovery Program works toward this goal the number of release sites has grown. There are three active release sites in California,

one in Arizona, and one in Baja, Mexico.

Condor Puppet

Condor hatching video

• http://www.youtube.com/watch?v=XNkV02P8Ysc

Condor Training

San Diego Zoo Condor Cam

• http://www.sandiegozooglobal.org/video/condor_cam

Condor video: Condor nest update

• http://www.youtube.com/watch?v=nO8Ro94l5C4

Condor References

• http://www.sandiegozoo.org/animalbytes/t-condor.html

• http://content.usatoday.com/communities/sciencefair/post/2010/10/california-california-condor-population-reaches-100/1?csp=usat.me

Critical Thinking

• What are some differences between the stories of the condor and the passenger pigeon that might give the condor a better chance of avoiding premature extinction than the passenger pigeon had?

Little Fish, Big ControversyThe Story of Snail Darter, the Endangered Species Act,

TVA, and the Tellico Dam

The Snail Darter Story: Connection to History, Economics, Politics

• In August of 1973, a University of Tennessee biologist discovered a small fish species, the snail darter, in the Little Tennessee River while conducting research involving a lawsuit around construction of the Tellico Dam. Creation of the Tellico Reservoir, to be created by the Tellico Dam, the scientist predicted, would alter the snail darter's habitat to the point of extirpation. Opponents of the dam used the snail darter as leverage in attempting to halt construction and invoked the Endangered Species Act to do so. The Tennessee Valley Authority argued that (1) since the Act was passed after the project began (December 1973) it did not apply and (2) after Congress passed the Endangered Species Act it continued to appropriate funds to Tellico; therefore, Congress did not intend for the ESA to apply to Tellico.

• The Supreme Court's ruling in Tennessee Valley Authority vs. Hill (1978) was unprecedented. Speaking for the majority, Chief Justice Warren Burger announced the court's decision to rule in favor of the snail darter, halting construction on the Tellico Dam. Caution was taken not to say that Congress broke the law by funding the Dam. According to the ruling, the language and intended goals of the Endangered Species Act are clear: there are no exceptions for project like Tellico that were well under way when Congress passed the Act, and that Congress' intent was to slow, stop and reverse the trend toward species extinction—no matter the cost.

• Soon after the ruling, Tennessee legislators in favor of the Tellico Dam began an appeals process which included sponsorship of an amendment to the Act that would form an investigative committee whenever controversy arose over a listing. Dubbed the "God Squad," even this committee deemed the Tellico Dam project “dangerous” to the snail darter and "economically not beneficial." Nonetheless, legislators appealed again, and the case reached President Jimmy Carter's desk in 1979. Although he wanted to veto the bill that would override the Supreme Court's decision, political realities and other pressing issues, like the Panama Canal Treaty, forced the President to sign it on September 25, 1979. As the gates closed on the Tellico Dam and the Tellico Resevoir formed in subsequent years, several other populations of the snail darter were found elsewhere around the country, and the species was delisted in the late 1980s.

• The snail darter controversy not only illustrates the conflict between conservation biologists and economic interest groups, it also shows just how entwined science and politics are in conservation legislation. Biologists and politicians alike have suggested ways to mitigate the problems arising from this unhappy marriage, which will be discussed in later sections.

• http://www.macalester.edu/environmentalstudies/students/projects/citizenscience2007/endangeredspecies/controversy.html

Homework Snail Darter

• What were some of the objections to the Tellico dam project?

• Why did the dam project get so far along before the environmentalists called for a halt to it?

• What were the arguments for continuing with the project?

• What ultimately happened to the snail darter?• What lessons can we learn from this controversy that will

help us solve environmental, economic, legal problems in the future?

The Tellico Dam and the Snail DarterConnections to history, politics, and economics

• http://www.utc.edu/Faculty/John-Tucker/Courses/esc430/esc430mat/darter/tellico.html

• http://bgpappa.hubpages.com/hub/The-Story-Of-The-Snail-Darter

Cathranthus roseus,MadagascarHodgkin's disease,lymphocytic leukemia

Rauvolfia

Rauvolfia sepentina,Southeast AsiaAnxiety, highblood pressure

Foxglove

Digitalis purpurea,EuropeDigitalis for heart failure

Pacific yew

Taxus brevifolia,Pacific NorthwestOvarian cancer

Cinchona

Cinchona ledogeriana,South AmericaQuinine for malaria treatment

Neem tree

Azadirachta indica,IndiaTreatment of manydiseases, insecticide,spermicide

Rosy periwinkle

Fig. 8-7, p. 158

Nature’s pharmacy. Part’s of these and a number of other plantand animal species (many of them found in tropical forests) are used to treat a variety of human ailments and diseases. About 2,100 of the 3,000 plants identified by the National Cancer Institute as sources of cancer fighting chemicals come from tropical forests.

Why should we care if plant species become extinct?

Zoos and Aquariums for Protection

• Collect species with long-term goal of returning them into habitat

• Egg pulling• Captive breeding• 100–500 captive individuals to avoid

extinction• 10,000 individuals to maintain

capacity for biological evolution

8-3 How Do Humans AccelerateSpecies Extinction?

• Concept 8-3 The greatest threats to any species are (in order) loss or degradation of its habitat, harmful invasive species, human population growth, pollution, climate change, and overexploitation.

Causes of Endangerment and Premature Extinction (HIPPCO)

• Habitat destruction

• Invasive species

• Population growth

• Pollution

• Climate change

• Overexploitation• know for exam

Fig. 8-8, p. 160

Causes of Depletion and Premature Extinction of Wild Species

• Population growth

• Rising resource use

• Undervaluing natural capital

• Poverty

• Habitat loss

• Habitat degradation and fragmentation

• Introduction of nonnative species

• Commercial hunting and poaching

• Sale of exotic pets and decorative plants

• Predator and pest control

• Pollution

• Climate change

• Overfishing

Underlying Causes

Direct Causes

Natural Capital Degradation

Review for exam

Habitat Loss

• Deforestation of tropical areas greatest eliminator of species

• Endemic species-species that is found in only one area

• Habitat fragmentation- by roads, logging, agriculture, and urban development, occurs when a large, intact area of habitat is reduced in area and divided into smaller, more scattered, and isolated patches, or “habitat islands”

Stepped Art

Indian Tiger

Range 100 years agoRange today

Black Rhino

Range in 1700Range today

African Elephant

Probable range 1600Range today

Asian or Indian Elephant

Former rangeRange today

Fig. 8-9, p. 161

Reductions in the ranges of four wildlife species, mostly as the result of habitat lossand hunting. What will happen to these and million of other species when the world’s human population doubles and per capita resource consumption rises sharply in the next few decades?

Case Study: Declining BirdSpecies (1)

• Decline of ~70% of ~10,000 known species

• 12% threatened with extinction

• Birds around humans benefited, but forest species declined

• Long-distance migrants – greatest decline

Case Study: Declining BirdSpecies (2)

• Reasons – Habitat loss – Habitat fragmentation– Climate change

• Birds are environmental indicators (species that serve as early warning that a community or ecosystem is being degraded)

• Perform economic and ecological services

Species Introductions

• Most beneficial – food crops, livestock, pest control

• 500,000 alien invader species globally

• 50,000 nonnative species in the U.S.

• Some definitely not beneficial

European wild boar(Feral pig)

Deliberately Introduced Species

Purple loosestrife European starling African honeybee(“Killer bee”)

Nutria Salt cedar(Tamarisk)

Marine toad(Giant toad)

Water hyacinth Japanese beetle Hydrilla

Fig. 8-10, p. 163

Gypsy moth larvae

Accidentally Introduced Species

Sea lamprey(attached to lake trout)

Argentina fire ant

Brown tree snake

Eurasian ruffe Common pigeon(Rock dove)

Formosan termite

Zebra mussel Asian long-horned beetle

Asian tiger mosquito

Fig. 8-10, p. 163

Case Study: The Kudzu Vine“the vine that ate the South”

• Kudzu imported from Japan to control soil erosion• Growth is so prolific that it engulfs hillsides,

gardens, trees, abandoned houses, cars, and anything in its path

• Uses– Asians use powdered starch in beverages– Edible – Source of tree-free paper– Japanese kudzu farm in Alabama

Fig. 8-11, p. 164

Disruptions from AccidentallyIntroduced Species

• Downside of global trade

• Downside of traveling

• Argentina fire ant

• Burmese python

• Zebra mussel

Fig. 8-12, p. 165

Zebra Musselsattached to a watercurrent meterin Lake Michigan.This invader entered the Great Lakesthrough ballastwater dumped froma European ship.

Prevention of Nonnative Species (1)

• Identify characteristics of successful invaders

• Detect and monitor invasions

• Inspect imported goods

• Identify harmful invasive species and ban transfer

Prevention of Nonnative Species (2)

• Ships discharge ballast waters at sea

• Introduce natural control organisms of invaders

Fig. 8-13, p. 165

Review for exam: ex zebra musselsGeneralist, rapid reproductive rate, lack of natural enemies+

Fig. 8-14, p. 166

Human Choices Drive Extinction

• Human population growth

• Excessive, wasteful consumption

• Use of pesticides

• Climate change

DDT and Bioaccumulation

• 1950s–1960s fish-eating bird populations drop

• DDT biologically magnified in food webs

• Bird’s eggshells thin and fragile

• Leads to unsuccessful reproduction

DDT in water0.000003 ppm,or 3 ppt

DDT in fish-eatingbirds (ospreys)

25 ppm

DDT in largefish (needle fish)2 ppm

DDT in smallfish (minnows)0.5 ppm

DDT inzooplankton0.04 ppm

Fig. 8-15, p. 166

Bioaccumulation and biomagnification. DDT is a fat-soluble chemical that can Accumulate in the fatty tissues of animals. In a food chain or web the accumulated DDT is biologically magnified in the bodies of animals at each higher trophic level.

• Bioaccumulation= an increase in the accumulation of a chemical in specific organs or tissues at a level higher than would normally be expected

• Biomagnification= increase in concentration of DDT, PCBs, and other slowly degradable, fat soluble chemicals in organisms at successively higher trophic levels of a good chain or web

Case Study: Where Have All the Honeybees Gone?

• Honeybees responsible for 80% of pollination of insect-pollinated plants

• Population down 30% since the 1980s– Pesticides– Parasitic mites– Invasive African honeybees

• 2008: 36% of honeybee colonies lost– Colony collapse disorder– New nicotine-based pesticides to blame?

Study Finds Cause of Colony Collapse Disorder in Bees

• http://www.telegraph.co.uk/gardening/beekeeping/8050583/Study-finds-causes-of-Colony-Collapse-Disorder-in-bees.html

Illegal Killing and Trading of Wildlife

• Poaching endangers many larger animals, rare plants

• Over two-thirds die in transit

• Illegal trade: $1.1 million per hour

• Wild species depleted by pet trade

• Exotic plants often illegally gathered

Fig. 8-16, p. 168

Fig. 8-A, p. 168

The Value of Wild Rare Species

• Declining populations increase black market values

• Rare species valuable in the wild – eco-tourism

• Some ex-poachers turn to eco-tourism

Rising Demand for Bush Meat

• Demand increasing with population growth

• Increased road access

• Loggers, miners, ranchers add to pressure

• Local and biological extinctions

• Spread of HIV and Ebola virus

Fig. 8-17, p. 169

8-4 How Can We Protect Wild Species from Premature Extinction?

• Concept 8-4 We can reduce species extinction and help to protect overall biodiversity by establishing and enforcing national environmental laws and international treaties, creating a variety of protected wildlife sanctuaries, and taking precautionary measures to prevent such harm.

International Treaties

• Convention on International Trade of Endangered Species (CITES)

• Convention on Biological Diversity (CBD)

U.S. Endangered Species Act (1)

• National Marine Fisheries Services – ocean species

• U.S. Fish and Wildlife Service – other species

• Listings based on biological factors

• Forbids federal agency projects that jeopardize listed species or habitats

U.S. Endangered Species Act (2)

• Fines violations on private land

• Illegal to sell or buy listed species

• 1,318 species listed

• USFWS and NMFS supposed to prepare recovery plan – 86% species in 2009

U.S. Endangered Species Act (3)

• Successful recovery plans include American alligator, grey wolf, and bald eagle

• Lax enforcement of imports and exports

• Amended to give private landowners economic incentive to save species

Science Focus: Accomplishments of the Endangered Species Act

• Biologists defend limited success– Species listed only when gravely threatened– Takes long time for species to recover– >50% endangered species improving

• Need more funding

• Develop recovery plans more quickly

• Core habitat established when listed

Protection of Marine Species

• ESA and international treaties protect endangered marine reptiles and mammals

• Challenges to protecting marine species– Limited knowledge of species

– Difficulty in monitoring and enforcing treaties – open oceans

Sea Turtles Threatened

• Six species critically endangered

• Loss or degradation of habitat

• Illegal harvest of eggs

• Threats from fishing methods

• Protection measures have helped

Fig. 8-18, p. 171

Case Study: Protecting Whales (1)

• Easy to kill

• International Whaling Commission– Sets quotas

– Often ignored

– No enforcement powers

• 1986: Whaling ban, although violated, greatly decreased whale kills

Case Study: Protecting Whales (2)

• Key countries that violate whaling ban– Japan

– Norway

– Iceland

Fig. 8-19, p. 172

Establish Wildlife Refuges

• National Wildlife Refuge System• Wetland refuges: ~75%• 40 million American visitors• 20% of listed species in refuge system• Many refuges in disrepair, and many

allow mining, oil drilling, and off-road vehicles

Storing Genetic Information

• Gene or seed banks

• Botanical gardens and arboreta

• Farms – commercial sale of endangered species removes pressure

• Flagship species

The Precautionary Principle

• When substantial preliminary evidence indicates an activity could harm humans or the environment, we should take precautionary measures to prevent or reduce the harm

• Do even if cause-and-effect relationships are not yet clearly established

• “Better safe than sorry”

Three Big Ideas from This Chapter - #1

We are greatly increasing the premature extinction of wild species by destroying and degrading their habitats, introducing harmful invasive species, and increasing human population growth, pollution, contributing to projected climate change, and over-exploitation.

Three Big Ideas from This Chapter - #2

We should prevent the premature extinction of wild species because of the economic and ecological services they provide and because they have a right to exist regardless of their usefulness to us.

Three Big Ideas from This Chapter - #3

We can work to prevent the premature extinction of species and to protect overall biodiversity by using laws and treaties, protecting wildlife sanctuaries, and making greater use of the precautionary principle.