Download Conservation of Biodiversity - IB BiologyMr. Van Roekel Salem High

Conservation of
Biodiversity
VAN ROEKEL
IB BIO II
Assessment Statements
G.4.1 Explain the use of biotic indices and indicator species in
monitoring environmental change
G.4.2 Outline the factors that contributed to the extinction of one
named animal species
G.4.3 Outline the biogeographical features of nature reserves that
promote conservation of diversity
G.4.4 Discuss the roles of active management techniques in
conservation
G.4.5 Discuss the advantages of in situ conservation of endangered
species (terrestrial and aquatic reserves)
G.4.6 Outline the use of in situ conservation measures, including captive
breeding of animals, botanic gardens, and seed banks
Indicator Species
Indicator Species: species that are very sensitive to environmental
changes
◦ Species will not be present in areas of high pollution
◦ Absence/presence of indicator species helps identify clean/polluted
environments
◦ Lichens – sensitive to air pollution and presence of mercury/lead
◦ Macroinvertebrates – found in rivers and streams, sensitive to water
pollution
Biotic Index
Measures the health of an ecosystem by measuring the number of species
tolerant to pollution and the number of species intolerant to pollution
◦ The more intolerant species the cleaner the environment
Extinction
When environmental changes occur, the new selection pressures can
lead to the extinction of previously successful animals
Factors that contribute to extinction
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Habitat Destruction
Pollution
Overfishing or Overhunting
Climate Changes
Invasive Species
https://www.youtube.com/watch?v=hDbz2dpebhQ
Extinction of Dodo
Caused by arrival of Dutch to environment in 1600s
◦ Deforestation and habitat loss
◦ Hunting for food
◦ Invasive Species, rats, dogs, cats from ships
Lack of fit characteristics
◦ Flightless
◦ Short Legs
◦ No behavioral adaptation to avoid predation
Nature Reserves Promote
Biodiversity
Areas of aquatic and terrestrial ecosystems that are protected by law to
conserve biodiversity
Nature Reserves are beneficial because
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Control Invasive Species
Control Human exploitation
Legally protect endangered species
Opportunities for research
Restoration of degraded areas
Nature Reserves & size
Nature reserves have very large areas
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Larger Habitats
More resources & breeding sites
More niches
Allows for migration
Establishes different ecosystems
More biodiversity
Smaller habitats have higher risks of extinction from unexpected factors
Nature Reserves & Edge Effect
Ecology at edge of ecosystems is different from center habitats
Disturbances from outside extends into ecosystem
◦ Edges of forest have fewer trees, more sunlight and wind, less moisture.
◦ Organisms have more competition from other species
Edge effect is controlled in reserves
Nature Reserves and Corridors
Greenbelts, hedgerows, and even tunnels under highways can provide
corridors that connect otherwise isolated habitats
Allows species to expand over larger areas
Problems include
◦ Narrow corridors lead to exposure to predation
◦ Invasive species can enter habitat
◦ Corridors can cause controversy with humans
Management of Reserves
Active intervention occurs when humans intervene to restore areas and
protect natural habitats in a nature reserve
Includes:
◦ Restoration – restore land to natural state, can include clearing existing
species and replanting
◦ Recovery of threatened species – maintains habitats of endangered species
and reintroduction
◦ Removal of introduced species – removal of invasive species that have
dominated environment
◦ Legal Protection – prevent activity that harms native animals and plants,
such as development and pollution
◦ Funding and prioritizing – used to fund preserves
In situ conservation
Keeps organisms in the situation they belong and protect them by:
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Maintaining the original habitat
Defending from predators
Removing and preventing invasive species
Having large areas to maintain large populations
Large populations maintain genetic diversity
Ineffective when:
◦ Species is too endangered
◦ Small populations can’t maintain genetic diversity
◦ Uncontrollable destructive forces (human incursion, invasive species, natural
disasters)
Ex situ Conservation
Usually a last resort if species can not safely remain in natural habitat,
or population is too small
Accomplished in variety of ways
◦ Captive Breeding
◦ Cultivations of plants in botanical gardens
◦ Storing seeds in seed bank
Captive Breeding
Many zoos have facilities dedicated to captive breeding
Goal is to increase reproductive output to ensure survival of offspring
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Artificial insemination
Embryo transfer to surrogate
Cryogenic eggs
Human raised young
Keeping a pedigree (minimize inbreeding)
Problem - Difficulty reintroducing organisms into natural environment
Botanical Gardens & seed
banks
Botanical Gardens
◦ Easy care and breeding
◦ 80,000 plants are grown outside of natural environment
Seed Banks
◦ Seeds kept in cold, dark conditions
◦ Prevents germination, allows for later use (decades)
◦ 10,000 – 20,000 different species have seeds stored in seed banks
Population
Ecology
VAN ROEKEL
IB BIO II
Assessment Statements
G.5.1 Distinguish between r-strategies and k-strategies
G.5.2 Discuss the environmental conditions that favor either r-strategies
or k-strategies
G.5.3 Describe one technique used to estimate the population size of an
animal species based on mark-release-recapture method
G.5.4 describe the methods used to estimate the size of commercial fish
stocks
G.5.5 outline the concept of maximum sustainable yield in the
conservation of fish stock
G.5.6 Discuss international measures that would promote the
conservation of fish
r-strategy vs. k-strategy
Two strategies for survival and reproduction
r-strategy makes the use of disposable offspring, organisms produce
hundreds or thousands of offspring and don’t care for them after birth
k-strategy occurs when parents have few offspring and invest time and
energy into raising, nurturing and protecting offspring
r-strategy vs. k-strategy
Characteristic
r-strategy
k-strategy
Life span
Short
Long
# of offspring
Many
Few
Onset of maturity
Early
Body size
Small
Late- after long
period of parental
care
Large
Reproduction
Once during
lifetime
More than once
during lifetime
Parental care
None
Very likely
Environment
Unstable
Stable
Capture-mark-recapture
Method used to estimate the number of animals in an ecosystem
Capture some of population, mark and release them
Second sample taken consisting of marked and unmarked individuals
Proportion of marked to unmarked organism is same as proportion of
original marked to whole population
Formula
n3
n1
n2
N
N
=
N1 x n2
n3