Chapter 22 Sustaining Wild Species

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Chapter 22Sustaining Wild Species
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What Major Factors Affect Biodiversity?
3
Reduce Biodiversity Loss?

• Species Approach
• Goal protect species from premature extinction
• Strategies Identify endangered species, protect
  their 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 nonnative species from
  protected areas, manage protected areas to
  sustain native species, restore degraded
  ecosystems.

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What are the Three Types of Extinction?

• Local Extinction - when a species is no longer
  found in an area it once inhabited, but it is
  still found in the world.
• Ecological Extinction - when so few members are
  left that it can no longer play its ecological
  roels in the biological communities where it is
  found.
• Biological Extinction - when a species is no
  longer found anywhere on earth.

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What are Endangered Vs. Threatened Species?

• Endangered has so few individual survivors that
  the species could soon become extinct over all or
  most of its natural range.
• Threatened or Vulnerable Species is still
  abundant in its natural range, but has declining
  numbers and will likely become endangered in the
  near future.

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What are Estimates of Species Extinction Rates
Based On?

• Species Area Relationship number of species
  present increases with the size of the area
• Population Viability Analysis (PVA) a risk
  assessment mathematical and statistical model
  that predicts the probability that a population
  will persist based on
• Current and projected habitat conditions are
  resources needs
• Genetic Variability
• Interactions with Other Species
• Reproductive Rates and Population Dynamics
• Minimum Viable Population (MVP) the smallest
  number of individuals necessary to ensure the
  survival of a population in a region for a
  specified time period.

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What are Estimates of Species Extinction Rates
Based On? Cont.

• Minimum Dynamic Area (MDA) the minimum area of
  suitable habitat needed to maintain the minimum
  viable population
• Models such as theory of island biogeography
• Changes in species diversity at different
  latitudes
• Different assumptions about the earths total
  number of species, the proportion of these found
  in the tropical forests and the rate at which
  tropical forests are being cleared.

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Why Should We Care About Biodiversity?

• Instrumental Value - their usefulness to us
• Utilitarian - food, fuel, lumber, paper,
  medicine,
• Ecological services - including phosynthesis,
  pollination, soil formation, nutrient recylcing,
  pest control, climate regulation, flood control,
  irrigation water, waste decomposition, absorption
  and detox of plants, water purification
• Non-utilitarian - existence, aesthetic, value for
  future
• Intrinsic Value - because they exist, regardless
  of whether they have any usefulness to us.
• Ethical responsibility
• Each species has an inherent right.

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What is the Role of Habitat Loss and Degradation?

• Greatest Loss of Species Due To
• Tropical deforestation
• Destruction of coral reefs and wetlands
• Plowing of grasslands
• Pollution of fresh water streams, lakes, and
  marine habitats
• Habitat Disturbance in the US is due to
• Agriculture
• Commercial development
• Water development
• Outdoor recreation
• Livestock grazing
• Pollution

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What is the Role of Habitat Fragmentation?

• Occurs when a large continuous area of habitat
  is
• Reduced in area
• Divided into a patchwork or isolated areas or
  fragments.
• Three main problems causing fragmentation are
• A decrease in sustainable population size for
  species.
• Increased surface edge making species more
  vulnerable to predators, competition, wind, fire
• Creation of barriers that limit the ability of a
  species to disperse and colonize new areas, find
  enough to eat, and find mates.
• Species vulnerable to habitat fragmentation are
• Rare
• Need unhindered room
• Low reproductive capacity
• Specialized niches
• Sought by people for furs, food, medicines

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What Harm Do Nonnative Species Cause?

• Cost billions in damage and pest control
• Threaten endangered and threatened species
• Blamed for extinctions.
• Deliberately Introduced
• Benefits - depend on them for ecosystem services,
  food, shelter, medicine, and aesthetic enjoyment.
  
• Harmful - can trigger ecological disruptions
• Accidentally Introduced
• Know examples
• Prevention - screen out harmful invaders, set up
  better inspection of goods, pass international
  laws, displace water in ships

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Extinction Threats

• Commercial Hunting and Poaching
• Predators and Pest Control
• Market for Exotic Pets and Decorative Plants
• Climate Change and Pollution

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The Research and Legal Approach to Protecting
Wild Species

• Bioinformatics - why is it helpful?
• Convention of International Trade in Endangered
  Species (CITES)
• Signed by 152 countries
• 900 species can not be commercially traded
  29,000 are restricted.
• Why doesnt it work?
• Convention of Biological Diversity (CBD)
• Ratified by 172 countries
• Need to reverse the global decline of biological
  diversity
• Why doesnt it work?

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National Laws To Protect Endangered Species

• Lacey Act of 1900 - prohibits the transporting of
  live or dead wild animals across state borders
  without a federal permit.
• Endangered Species Act (ESA) of 1973 (amended in
  1982 and 1988) - makes it illegal for Americans
  to import or trade any product made from an
  endangered or threatened species unless it is for
  approved scientific purpose or to enhance the
  survival of the species.

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How are Private Landowners Encouraged to Protect
Endangered Species?

• Habitat Conservation Plans (HCP)- landowners,
  developers, and loggers are allowed to destroy
  some habitat and kill some species in exchange
  for protecting those species by
• Setting aside a preserve
• Paying to relocate the species
• Paying money to have the government buy suitable
  habitat elsewhere?
• Improving the plans would require
• Scientific standards for the plans
• Scientific review committee
• More comprehensive efforts by land owners

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Is the ESA working?

• Rising rates of endangered and threatened species
• 1/3 of our species are at risk of extinction
• There are 30,000 species at high risk of
  extinction, but only 1,250 protected
• Difficult to be listed and habitat protected.
• There is little enforcement

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Should the Endangered Species Act Be Weakened?

• Yes
• It hasnt worked
• It has caused economic losses
• Efforts have been made to weaken it by making it
  voluntary, giving compensation to land owners,
  asking for government overrides and exemptions,
  prohibiting the public from interfering.
• No
• It hasnt been a failure
• It is has not caused economic loses
• Most projects have been approved
• Federal projects are exempt from HCP
• The ESA can be more scientifically sound by
• Increasing funding
• Developing recovery plans
• Developing new guidelines
• Creating emergency survival habitats for newly
  listed species

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New System?

• o Determine the species and ecosystems of a
  country
• o Locate and protect the most endangered
  ecosystems and species
• Give private landowners
• 1) financial incentives
• 2) technical help
• 3) assurances of no additional requirements.

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Is it Worth It To Protect Endangered and
Threatened Species?

• Proponents
• To judge the health of an ecosystem, we should
  consider those that
• Play keystone roles and protect keyston resources
• Tolerant to environmental change
• Better to conserve 10 key species than 10,000
  weak ones
• Opponents
• We are already deciding by default
• With limited knowledge, the selective approach is
  more effective and a better use of funds.

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The Sanctuary Approach

• Wildlife Refuges
• Gene Banks
• Botanical Gardens
• Farms
• Zoos
• Understand and know about breeding populations of
  captive species
• Why reintroductions fail
• Aquariums

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What is Wildlife Management?

• Uses laws to regulated hunting and fishing
• Establishes harvest quotas
• Develops population management plans
• Improves wildlife habitat
• Manipulating vegetation and water supplies
• Sport hunting
• What are the pros and cons?
• Preserving flyways