Transcript Chapter 11

Chapter 11
Sustaining Biodiversity: The Species
Approach
Species Extinction
 Local extinction:
 Ecological extinction:
 Biological extinction:
 Endangered Species:
 Threatened Species:
 30,000 plants and animals are
endangered or threatened.
Species Extinction
 Estimating extinction rate is hard to do.
 Extinction can take a long time
 We only know of 1.4 million species when there
could be 4-100 million.
 We have little knowledge on most species.
 Compare current extinction to fossil records
of past extinctions.
 Observe how the # of species present
increases with size of an area
 Species-area ratio suggest that on average a
90% habitat loss causes the extinction of about
50% of species.
Characteristic
Low reproductive
rate
(K-strategist)
Specialized niche
Narrow distribution
Examples
Blue whale, giant panda,
rhinoceros
Blue whale, giant panda,
Everglades kite
Many island species,
elephant seal, desert pupfish
Feeds at high trophic Bengal tiger, bald eagle,
grizzly bear
level
Fixed migratory
patterns
Blue whale, whooping crane,
sea turtles
Rare
Many island species,
African violet, some orchids
Commercially
valuable
Snow leopard, tiger,
elephant, rhinoceros,
rare plants and birds
Large territories
California condor, grizzly
bear, Florida panther
Fig. 11-4, p. 225
Species Extinction
 Effects of human activities on
extinction rates.
 Extinction rate was 0.0001% before
humans
 0.01% to 1% now
 1% extinction rate would mean at least 1/5
of plants and animals will be extinct by
2030 or ½ by 2050.
Importance of Wild Species
 Instrumental value
 Food crops, fuel wood, lumber, paper, medicines
 62% of all cancer drugs were created by
bioprospecting discoveries.
 Genetic information
 Allows species to change with changing
environments
 Humans use this info for new crops and foods
 Wild species provide us with ways to learn how
nature works and sustains itself
 Recreational pleasure
 Ecotourism- $500 billion/yr (1 male lion living
to 7 will generate 515,000 in tourists dollars in
Kenya but only $1,000 if killed for skin)
H.I.P.P.O
Habitat loss, degradation and fragmentation
 HIPPO:
 Greatest threat is habitat loss, degradation and
fragmentation
 Deforestation of the TRF is leading cause
 Hotspots are very vulnerable
 Most national parks and nature reserves are
surrounded by damaging logging, mining and
industrial activities.
 Habitat fragmentation:
 Block migration routes and cause species population
to decrease in smaller areas
 More vulnerable to predators, competition, disease
and catastrophic events
 Increase road kill
H.I.P.P.O
Invasive species
 2nd biggest cause of extinctions
 Most species introduced to new areas
are beneficial
 Crops, cattle, poultry
 1 in 7 nonnative species are harmful
 No natural predators, competitors,
parasites, or pathogens to control
population
 Cost U.S. $137 billion/year ($16
million/hr)
H.I.P.P.O
Invasive species
 Accidently introduced invasive species
 Stowaways in aircrafts, ballast water
from tankers, hitchhikers on imported
products
 Comb jellies in black sea have wiped out
some native fish populations b/c the feed
on the planktonic larvae
 Zebra mussels in Great Lakes have blocked
water pipe systems
 Fire ants were introduced in Mobile, Al and
have caused $600 million/yr damage to
crops and power poles.
H.I.P.P.O
Invasive species
 Solutions
 Prevent them from being introduced
 Research to identify major characteristics that
allow species to become successful invaders
 Increase ground surveys and satellite observations
to detect and monitor species invasions to better
predict spreading and future invasions.
 Improve inspections of imported goods
 Identify major harmful invasive species and pass
law banning their transfer from country to country
 Require cargo ships to discharge their ballast
water or other methods to ride possible invasive
species
 Increase research to find and introduce natural
predators, parasites, and disease causing bacteria
and viruses to control populations.
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
H.I.P.P.O
Population growth, Pollution and Climate change
 Population growth and excessive
waste have caused many premature
extinctions
 Pesticides- kill 1/5 of U.S. beneficial
honeybee colonies, 67 million birds and
6-14 million fish each year.
 Climate change
 Could drive more than ¼ of all land
animals and plants to extinction by the
end of the century.
H.I.P.P.O
Overexploitation
 Legitimate trade of wildlife is worth $10
billion/yr.
 Illegal trade is worth $6-10 billion/yr
 Some species (dead or alive) are worth 100s of
1000s of dollars
 Killing species we don’t like
 Some species are killed because they are
considered pests (wolfs eating cattle or
elephants trampling crops)
 Exotic pets and plants
Protecting Wild Species: Legal and
Economic Approaches
 1975 Convention on International Trade in
Endangered Species (CITES)
 169 countries signed
 900 species that can not be traded
 5000 animals and 28,000 plants trade is
restricted
 Convention on Biological Diversity (CBD)
 188 countries signed
 Reverse the global decline of biological diversity
Protecting Wild Species: Legal and
Economic Approaches
 U.S. Endangered Species Act 1973
 Identify and legally protect endangered species
in the U.S.
 National Marine Fisheries Services (NMFS)
 U.S. Fish and Wildlife Services (USFWS)
 Decisions must be based on biological facts only
 Between 1973-2006 the # on the ES list went
from 92 to 1260
 Once a species is on ES list a plan is put in to
place to help recovery.
Protecting Wild Species: Legal and
Economic Approaches
 Encouraging private landowners to
protect endangered species
 Habitat conservation plans
 Part of critical habitat is allowed to be
destroyed in exchange for taking steps to
protect species (setting aside part of
habitat, pay to relocate species, pay
government to purchase suitable habitat
elsewhere)
 Safe harbor agreements:
 Voluntary candidate conservation
agreements:
Protecting Wild Species: The
Sanctuary Approach
 Since 1903 there are 544 refuges
 More then ¾ of refuges serve as vital wetlands
for migratory birds
 More then 1/5 of endangered and threatened
species have habitats in refuges
 Harmful activities occur in about 60% of
refuges
 Invasive species are a huge threat
 Too much fishing and hunting and use of boats
and off road vehicles cause damage
Protecting Wild Species: The
Sanctuary Approach

National Refuge System Improvement Act (1997)


insuring that the biological diversity and integrity and
environmental health of the system are maintained.
Gene banks, botanical gardens, and wildlife farms

Gene banks:


Botanical gardens:


Cons: some seeds can’t be kept in a bank, expensive,
accidental destruction could destroy seeds
Cons: too little storage capacity and funding to preserve rare
and threatened species

Wildlife farms:

Long term goal to reintroduce endangered and threatened
species into the wild
Most don’t have money to successfully help threatened or
endangered species but are still beneficial because of
educational opportunities.
Zoos and Aquariums

Reconciliation Ecology
 Find ways to share the places we
dominate with other species
 Examples:
 For pollinators: Have communities agree
not to spray pesticides, plant gardens of
flowering plants, build nesting areas
 Use native vegetation- reduce the need
for water, and mowing (pollution)
 Roof top gardens
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