Chapter 9:

Sustaining

Biodiversity

Extinction Fossil record shows evidence of

extinction as a natural process:

Background extinction: loss of

species at a relatively low rate, often

due to changes in local conditions;

Mass extinction: abrupt increases in

extinction rates. Mass extinctions

believed to result from global climate

changes (e.g. meteorite impacts etc.);

Five mass extinctions during past

500 million years, last one ____ million

years ago.

•Species are becoming extinct ___________ times

faster than they were before modern times.

•By the end of this century, the extinction rate is

expected to be 10,000 times the background rate.

•Conservative estimates of extinction = 0.01-1.0%

Growth of human population will increase this loss

E.O. Wilson estimates that if 1% extinction rate,

1/2 of all species will be gone by 2100

Endangered Species: Species that has so few

individuals that the species could soon become

_______ over some or most of its natural range.

Threatened Species: Species that is still relatively

abundant, but because of ______________ is

likely to become endangered in the near future.

Threatened & Endangered Species

Percentage of Various Species Threatened with Premature Extinction

Worldwide about 25% of mammals are at risk of

extinction.

The highest percentages at risk are: apes & monkeys (46%) moles & shrews (36%) antelopes & cattle (33%)

Threatened & Endangered Species

• economic & ___________ importance:

• scientific & ecological importance: ecological

services include nutrient recycling, watershed

value, production of oxygen, moderating

climate, & detoxifying toxic substances;

• aesthetic & recreational importance:

Why Preserve Wild Species?

Example of medical uses: The blood from 500,000

horseshoe crabs is collected each year. A component

of the blood is used to screen injectable medicine for

bacteria.

Biomimicry Video: Planes and Butterflies Biomimicry=__________________________________________________________________________________

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Bioremediation: ___________________________ _________________________________________.

Example: A bacterium called Pseudomonas putida can be used to degrade napthalene, a product of petroleum refining, from contaminated soil.

Specific types of bioremediation:

Phytoremedition = Using a ______ to solve an

environmental problem. (phyto = _________ )

___________ can be used to absorb lead and

other heavy metals from water and soil.

Mycoremediation: Using a _______ to solve an

environmental problem. (myco=__________)

__________________can be used to breakdown

diesel fuel from a spill.

http://permaculturenews.org/2014/04/10/bi

oremediation-industrial-pollution-utilizing-

fungi-bacteria-plants-reduce-oil-pollution-

ecuadorian-amazon-basin-world/

Show first 2.5 minutes of video

Why Care About Bats?

80% of bat species are _______ -eaters that control pests that damage crop, mosquitoes populations etc.

(Ecological Service)

Certain bats are pollinators of crops like mangos, and cashews

Bats (including local population) threatened by white-nose fungus

Video: Bats Decline due to White-Nose Fungus

•__________________ ,

fragmentation & degradation

•_________(nonnative) species

•Population and resource use

growth

•Pollution

•Climate change & pollution

•Overexploitation

(poaching, overfishing etc.)

HIPPCO

Causes of Extinction & Depletion

•Indian

Tiger

•Black

Rhino

•African

Elephant

•Asian or

Indian

Elephant

Habitat Loss/Fragmentation Is Most Serious Threat to Biodiversity

•Former Range

•Current Range

Habitat Fragmentation Reduces Genetic Diversity in a Population

Area preserved for wildlife refugee must have adequate population size for genetic diversity

Why is Genetic Diversity Important?

_________________________________________ _________________________________________.

http://evolution.berkeley.edu/evolibrary/article/_0_0/agriculture_02

Managing populations of

waterfowl requires

multinational efforts to

protect habitats along the

flyways.

Case Studies

Introduction of Invasive Species is the 2nd biggest Cause of Biodiversity Loss

Nonnative species may have no natural

•_________

•Competitors

•Parasites

Examples: Kudzu in Southeastern US

Zebra Mussels in the Great Lakes

Zebra Mussels

Kudzu

Accidentally Introduced Species

Many accidentally introduced aquatic species were carried by the

_________________ in tankers or cargo ships.

Deliberately Introduced Species

Biological Control Gone Bad

In the 1930’s cane toads were introduced into

Australia to control beetle populations that was

devastating cane sugar crop.

Cane toad did not control the beetle population, yet its

population grew exponentially in Australia.

Cane Toads are poisonous, and are able to

outcompete many native species.

Discuss with your table partner:

Certain classes of animals, including mammals and amphibians, have higher extinction rates. Identify some characteristics that make species more vulnerable to extinction.

• ________________________(e.g., blue whale)

• specialized feeding habits (e.g., panda)

• feed at high trophic level- top of the food

chain (e.g., tiger)

• large size (e.g., elephant)

• limited breeding area (e.g., sea turtle)

• limited distribution (e.g., caribou)

Characteristics of Extinction–Prone Species:

• fixed migratory patterns (e.g., whooping crane)

• preys on livestock (e.g., timber wolf)

• small population size (e.g. endemic island species)

• _________________________(e.g. rhinos for horns)

• behaviors that contribute to extinction (e.g.,

Carolina parakeet- flocks hover over injured bird.)

Characteristics of Extinction–Prone Species Cont.

http://m.flickr.com/photos/wwfint/8043573027/

Why are top consumers more vulnerable to extinction?

Must be supported by a __________________ __________________________.

Much of energy consumed is given off as a heat.

Typically, only 10% of energy available for the next trophic level (step in the food chain).

Why are top consumers more vulnerable to extinction? Cont.

Greater risk of harmful concentrations of toxins that bioaccumulate (get stored in body tissue such as fat).

Due to the energy pyramid, toxins get biomagnified (_____________________) through the food chain.

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Island species often have behaviors that make them vulnerable to extinction.

Overfishing: Modern commercial fishing methods

enable increasing harvest. Many fish populations

decreasing drastically.

Case Studies

• National Marine Fisheries Service (NMFS) charged with

protection of marine species;

• U.S. Fish & Wildlife Service charged with listing &

protection of all other species;

Protecting Wild Species in the US

Endangered Species Act (ESA) of 1973 requires listing

& ________of endangered & threatened species in US.

Government Agencies Involved:

California Condor

Florida panther

International Treaties on Biodiversity

• 1975: Convention on International Trade in

Endangered Species (CITES)

– Signed by 172 countries

– International trade regulation for endangered

species. For example:______________________.

• 1992: Convention on Biological Diversity (BCD)

– Focuses on ecosystems

– Ratified by 191 countries (not the U.S.)

Example of an issue for consideration by CITES:

International trade of rhino horn is banned by CITES, but due to the high price of rhino horn poaching is a persistent problem. The next CITES delegation will consider whether to allow farming of rhino for their horns.

• Pro: _____________________________________ ______________________________________.

• Con: _____________________________________ ______________________________________.

Farming of crocodiles for their skins helped to preserve wild crocodile populations.

Protecting Biodiversity •Ecosystem approach: aims to preserve balanced

populations of species in their native habitats.

advantage: it focuses on ___________________ to

protect ecological integrity & provide habitat for the

majority of wild species.

•Species approach: based on identifying &

protecting endangered species on a case–by–case

basis.

Consensus among conservation biologists is that

protecting biodiversity requires both approaches

Preserving Adequate Habitat

• US Wilderness Society estimates that

a wilderness area should be at least

_____________in order to be

protected from human activity.

• About 1.8% of lower US land area is

protected as wilderness:

• In lower US only 4 are larger than

4,000 km2

4,000 km2 box

~63 km wide

Unlike traditional parks &

reserves, biosphere

reserves recognize _____

____________ for access

to sustainable use of

resources in parts of the

reserve.

Protecting Biodiversity