Conservation Biology
•  Goal-oriented science that seeks to counter the
current rapid decrease in biodiversity
•  “The Biodiversity crisis”- human activities alter
ecosystem processes, alter landscape and trigger
extinctions. The 6th great extinction
Benefits of diversity
•  Biophilia- innate connection to nature and life
•  Anthrocentric
–  Species are a natural resource for food, fibers, medicines, etc.
–  Do all species have an innate value? Are some worth more than others?
Who decides?
–  Ecosystem services
•  Often overlooked benefits to humans:
Air, water, soil, detoxification, decomposition, pollination, seed dispersal,
nutrient cycling, protection from UV, moderation of weather…aesthetic
beauty and infinite source of wonder
•  Estimated at $33 trillion/year (1997)- 2x global GNP
–  Other studies estimate at only
5-10 trillion dollars
–  Economic benefits of biodiversity exceed costs
of conservation by 100:1
•  The big conclusion from the study:
–  Environmental 'externalities' - economists' term for benefits from
resources that belong to no one in particular and so are enjoyed for freeare relatively huge. We should do something to account for them in
environmental regulations. What is the cost to NOT protecting the
environment?
Three Levels of biodiversity
1.  Genetic diversity
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Variation within and between
populations
Genetic diversity allows for
adaptation to changing conditions
If populations loose genetic
diversity they loose adaptive ability
Once genetic diversity is lost it
takes evolutionary time to get it
back
Three Levels of biodiversity
•  Genetic diversity
•  Species diversity
•  Habitat / community
diversity
Three Levels of biodiversity
2. Species diversity
–  Loss of species richness
–  13% of 9,040 bird species threatened
–  47% of all plants worldwide may be
threatened
–  20% of freshwater fish extinct of
threatened
–  Since 1900, 123 extinct freshwater
vert and inverts in North America
–  Many animals are in the Hundred
Heartbeats club
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Three Levels of biodiversity
3. Habitat / community
diversity
–  Extinction of one species
could have negative impact
on others in the system
–  Each system can have an
important impact on the
whole biosphere
–  Links are hard to study and
harder to predict.
Biodiversity “Hotspots”
•  1,500+ species, 70%+ habitat loss
•  Plant-centric, but account for ~60% of animal species
Four Five major threats to biodiversity
1.
2.
3.
4.
5.
Habitat destruction
Introduced species
Overexploitation
Disruption of food chains
Climate Change
Five major threats to biodiversity
1.  Habitat destruction
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Single greatest threat to biodiversity
Over 70% of extinct, endangered, threatened species
from loss of habitat
93% of reefs are damaged- 1/3 of fish species are in
coral reefs which make up only 0.2% of ocean.
Large variety of human uses impact habitat loss
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Habitat fragmentation
Living, food, recreation, materials, fuels, etc…
Landscape fragmentation
Habitat size is not the only issue, contiguous pieces are also
important
Five major threats to biodiversity
2. Introduced species
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Edge Effects
-diff species
-temp
-water
-wind
-fire
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Second biggest problem- linked to 40% of extinctions
“Exotic species”- species humans have moved from
one location to another, sometime intentionally,
sometimes not
Successful exotics often disrupt their new community,
prey on and/or compete with native species
50, 000 in U.S. alone, damage control = $130 billion
Some examples…
2
Carcinus maenas- Green
Crab
•  First collected on west coast in S.F.- 1989
•  Moved to Bodega Bay by 1993
•  Found in Monterey by 1994
MBA Seafood Watch
www.mbayaq.org/cr/seafoodwatch.asp
Five major threats to biodiversity
3.  Overexploitation
–  Human harvesting of plants and animals
exceeds ability of populations to rebound
–  Species especially susceptible are those
with low reproductive rates
–  The “inexhaustible seas”
Five major threats to biodiversity
4.  Disruption of food
chains
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* The Fifth Major Threat
Loss of one species in an
ecosystem can have
negative impacts on there
species
Remove the prey, the
predators will suffer
Loss of Keystone species
Since most organism do not
depend on just a single prey
species, this can be a very
difficult thing to quantify
Sea Level Rise
•  Human influenced
climate and ocean
change
•  A changing climate
will drive all of the
previous threats, and
add in others
Not from Sea Ice melt!
From thermal expansion and
melting of land-based ice
3
The Acid Ocean
•  While we worry over atmospheric
climate change, the real crisis of the
21st century will probably be in the
Ocean.
•  The battlefield of that crisis is the
Pacific, and Monterey Bay is Ground
Zero.
•  What will be the ecology of the acid
ocean? How will the food chain be
altered? What management practices
will need to be changed?
Future Ocean Food Web – Loss of biodiversity, low productivity, dominated by microbial recycling?
Ocean Acidification
pH variation
in the Pacific Ocean
The oceans absorb most of
our CO2 emissions
od
e rs
uc
What are the expected effects of
An acidified Ocean?
Pr
op
Zo
lan
kto
n fo
od
we
b
Up
per
Tro
p
hic
lev
els
Simplified Food Web,
Increased Microbial Dominance
Seafloor community
Data from Jim Barry, MBARI
Recovery from Disturbance
Microbial Remineralization
Additional stresses for
animals that are already
food-limited –
“Living on the edge”
a ry
im
Sinking Organic Debris
When CO2 dissolves into
the water it form Carbonic
Acid.
Pr
Restoration Ecology
•  Restoration ecology is the study of recuperating degraded,
damaged or destroyed ecosystems through active human
intervention
–  current extinction rate are 1000 to 10,000 times the ‘normal’ rate
(E.O. Wilson 1988)
•  The fundamental difference between conservation biology
and restoration ecology lies in their philosophical
approaches to the same problem:
–  Conservation biology attempts to preserve and maintain existing
habitat and biodiversity.
–  In contrast, Restoration ecology assumes that environmental
degradation and population declines are somewhat reversible
processes. Therefore, targeted human intervention can lead to
habitat and biodiversity recovery and eventual gains
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•  restore a natural disturbance
•  hastening natural successional
trajectories
•  increase the effective size of a habitat by
simply adding area or by planting habitat
corridors that link two isolated fragments
•  monitoring and management are crucial
for the long-term stability
•  working toward a single desired stable
state
Environmental Issues
The goal of restoration is not to
immediately recreate replacement
ecosystems, rather to “jumpstart” natural recuperative
processes.
•  Human impacts on
nutrient cycling
•  Combustion
byproducts
•  Increasing levels of
CO2
•  Pesticide and fertilizer
issues
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What will you do to make a
difference?
Climate Change
Loss of biodiversity
Habitat loss
Overexploitation
Introduced species
etc., etc., etc…
Shameless Plug:
Biol 31Environmental
Science
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