Transcript Biodiversity - Cathedral Irish

Biodiversity:
Who cares?
Which do you like better?
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B
Which do you like better?
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B
Which do you like better?
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B
Which do you like better?
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B
Which do you like better?
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B
Which do you like better?
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Which do you like better?
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B
What do you think biodiversity
means?
Biodiversity
What does “Bio” mean?
Bio =
Biodiversity
What does “Diversity” mean?
Diversity = Variety
Biodiversity is the variety of life on
Earth
• Scientists have identified more than 2 million species.
Tens of millions -- remain unknown
•The tremendous variety of life on Earth is made possible
by complex interactions among all living things including
microscopic species like algae and mites.
MUTUALISM
There are 3 components of
biodiversity
1.
Diversity of genes
Chihuahuas, beagles, and rottweilers are all dogs—
but they're not the same because their genes are
different.
Chihuahua
Beagle
Rottweilers
There are 3 components of
biodiversity
Diversity of species
For example, monkeys, dragonflies, and
meadow beauties are all different species.
Saki Monkey
Golden Skimmer
Meadow Beauty
There are 3 components of
biodiversity
Variety of ecosystems
Prairies, Ponds, and tropical rain forests are all
ecosystems. Each one is different, with its own
set of species living in it.
Paines Prairie
Florida Sand hill Pond
Hoh Rain Forest
Which is more diverse?
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B
Which is more diverse?
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B
Which is more diverse?
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B
Which is more diverse?
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B
Which has more cultural
diversity?
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B
Which has more
biodiversity?
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B
Which has more
biodiversity?
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B
Biodiversity has Value
1. Aesthetic reasons
Would you rather live in a world with or
without clear mountain streams, grizzly
bears, and orchids?
2. Ethical reasons
Do we have the right to drive other species
to extinction?
Do we have the right to leave the world in
worse shape for our children and
grandchildren than it was in when we were
born?
3. Medicines
Would we be better off without penicillin and
other pharmaceuticals derived from nature?
Would will be better off without future
discoveries of organisms that will provide
useful drugs and medicines?
4. Economic reasons
Would we be better off without the
estimated $33 trillion in ecosystem services
provided by the whole-earth ecosystem?
Example: soil formation, nutrient cycling,
food production and much more
5. Recreation
Americans spend $104 billion ever year on
wildlife related recreation (we spend $81
billion dollars each year on new automobiles)
Would we be better off without commercial
and sport fisheries?
Estimated Annual Global Economic Values
of Ecological Services Provided by Forests
Should we be concerned about
biodiversity?
What we know:
The Earth is losing species at an alarming rate
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In undisturbed ecosystems extinction = 1 species per
decade
Human activity is causing 10,000 species extinction
per year or 27 per day!
Threats to biodiversity
Habitat destruction
Invasive Species
Pollution
Human Population growth
Overharvesting
HIPPO
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Habitat destruction,
invasive species, pollution,
population (human), and
overharvesting
What are the main threats to biodiversity?
I. Habitat destruction
Habitat destruction, degradation, and
fragmentation are probably the most
important causes of extinction today
Logged Rainforest in Malaysia
What are the main threats to biodiversity?
These hotspots of biodiversity =
1.5% of the Earth’s land, but if
they were destroyed, 1/3 of
Earth’s species would go extinct
Habitat Fragmentation:
fragmentation of an organism's
habitat
Building Roads into Previously Inaccessible
Forests
Habitat Fragmentation reduce population
sizes
Small populations are also especially vulnerable to
catastrophic events
Larger land can support more individual making
species
1. less vulnerable to natural disasters
2. Genetic problems (less inbreeding)
3. Demographic uncertainty (chance all members of
a single generation will be of the same sex
The threats to biodiversity generally
reduce population sizes
of native species
Managers try to maintain native populations well
above their minimum viable population (MVP) sizes
–the necessary population size to ensure between
90 and 95 percent probability of survival of a
population 100 to 1000 years into the future
II. Invasive Species
Non native species that
outcompetes with native species
eventually reducing biodiversity
People dumped pythons into
everglades when their pets
got too big
Introduced in 1800’s for
aesthetic reasons
What are the main threats to biodiversity?
1890: 100 Starlings were
introduced in NYC
European Starling
What are the main threats to biodiversity?
Gift from Japan in 1876 to
celebrate USA 100th year
Kudzu
U.S. Forest Invading
Nonnative Insect Species
and Disease Organisms
Invasive species can carry
pathogens
Dutch elm disease
transmitted to trees by
elm bark beetles. Since
1930, the disease has
spread from Ohio through
most of the country,
killing over half of the
elm trees in the northern
U.S.
The direct threats of
invasive species:
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preying on native species
out-competing native species for food
or other resources
causing or carrying disease
Releasing toxins
preventing native species from
reproducing or killing their young
The indirect threats of
invasive species
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Changing food webs: destroy or replace
native food source The invasive species
may provide little to no food value for
wildlife.
Decreasing biodiversity: outcompete
native species or destroying native
species
Altering ecosystem conditions changing
soil chemistry or the intensity of
wildfires.
What are the main threats to biodiversity?
III. Pollution: Directly and Indirectly kills
plants and animals
What are the main threats to biodiversity?
More people = increase in resources
IV. Population
The human population explosion is the root
cause of the other threats
Fig. 52.22
What are the main threats to biodiversity?
V. Overharvesting
Harvesting at rates exceeding the ability of
populations to rebound is not sustainable
Atlantic
Cod
Fishing Nets
Animals Killed because they
pose a threat to humans or
livestock
Pet Trades: Overharvesting
Endangered Species
Management and
Biodiversity Protection
1. Hunting and fishing laws
protect populations
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NO hunting during mating season
2. Endangered Species Act
of 1973
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Endangered species: imminent danger of
extinction
Threatened species: likely to become
endangered
Vulnerable species: naturally rare or
locally depleted by human activity
Which species do we save?
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5 billion to protect all species on list
Keystone species
Indicator species
Umbrella species
Flagship species
A. Keystone species
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species affect many other organisms in
an ecosystem and help to determine
the types and numbers of various
other species in a community.
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Example: weevil preys on Eurasian
Watermilfoil Without the weevil, the
Eurasian Watermilfoil would overtake the
plant species decreasing biodiversity
B. Indicator Species
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a species thought to be sensitive to and
therefore to serve as an early warning
indicator of environmental changes such
as global warming
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Example River otters have been used as
indicators of healthy, clean river systems
C. Umbrella Species
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these species indirectly protects the
many other species that make up the
ecological community of its habitat
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Example: Bees pollinate many different
types of flowers and fruit bearing plants
D. Flagship Species
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species are chosen for their
vulnerability or because they will appeal
to the public
example: panda bear
What cost is too much?
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Save Salmon or reduce cost to
electricity consumers?
Convention on International
Trade in Endangered Species
(CITES)
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Illegal to export or important animals
or animal body parts
What can you do to help?
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Plant a tree
Recycle paper and buy recycled paper
products
Choose wood alternative products for
decks, fencing, furniture
Remove invasive plants from your garden
and replace with native plants
Don’t transplant plants or seeds