370 Flashcards
(343 cards)
1
Q
Are we in the midst of a sixth mass extinction study
A
Life threatened
Birds 13%
Mammals 25%
Amphibians 41%
2
Q
The major threats to nature
A
- Habitat loss and degradation
- Overexploitation
- Invasive species
- Climate change
- Nitrogen depostion
3
Q
other threats to nature
A
pollution
disease
overuse of freshwater
cumulative impacts
4
Q
habitat degradation most detrimental to what kinds of species
A
specialists
5
Q
biggest threat that invasive species have
A
threaten biodiversity by predation and competition
6
Q
biggest threat from nitrogen deposition
A
ozone depletion
7
Q
agriculture use
A
1/3 of earths ice-free land
much of the other 2/3 is not suitable for agriculture
8
Q
human population growth
A
exponential
> 7 billion, almost 8
after 1960 +1billion/ 10-15years
9
Q
Human population 2050
A
9-12 billion ppl
10
Q
all the people on Earth could fit in
A
1 cubic mile
11
Q
what does the volumetric size of the worlds population show us
A
There are really not that many humans, our choices are the problem
12
Q
affluence
A
wealth
consumption of fuel, clothing, food, toys, etc.
13
Q
affluence and population growth
A
wealth increases child survivorship, decreased child mortality = decreased birth rate
14
Q
Demographic transition
A
birth/death rates vs years
pre-transition stage- Brate=Drate, pop low
early trans.- Drate plunges, Brate constant, pop starts to increase
mid transition- Brate drops, pop asymptotes
late transition- Brate=Drate lower than before, pop stabilizes
15
Q
Ecological impacts of a species on its environment
A
Total Impact (resource use) = abundance x per-capita resource use
16
Q
Can we use resources faster than they are supplied?
A
only by drawing down the capital, which will not last forever
17
Q
IPAT model of human impact on the environment
A
Impact = human Population size (P) x per capita Affluence (A) x Technology factor (T)
18
Q
The Kuznets Curve
A
environmental degradation vs per capita income
parabola, environment worsens up to turning point then improves with further income
19
Q
what happens after turning point in kuznets curve
A
wealthy enough to invest in saving the environment
20
Q
validity of kuznet hypothesis
A
pretty optimistic
21
Q
where is the human footprint highest
A
terrestrially - along the coastlines, low latitudes marine - most of the worlds ocean, lowest around Antarctica
22
Q
conservation science
A
seeks to understand human impact on species, habitats, ecosystems, and provide tools for protecting and restoring those parts of nature that we value
23
Q
what is demographic transition
A
pattern of changes in human birth and death rates as societies become more economically developed
24
Q
demography
A
study of population traits such as abundance, age structure, sex ratio, rates of birth and death
25
what happens in early stage demographic transition
births >> deaths due to improved living conditions, population explodes
26
world population growth rate
currently: 1.2%
peak: 2.1% 1965-1970
27
does the decreased population growth rate mean that population is not growing as much
no b/c base is increasing, growth rate is a lower % of a much larger number
28
population additions 1960s, now
1960: 72.5 million /yr
now: 86 mill ppl/yr
29
problem with IPAT model
may be viewed as anti-pop. growth and anti-consumption
| tech can be + also
30
benefits of ecosystem change
improvements in health: increased life expectancy, reduced child mortality
access to information: increased telephone use
increased wealth
31
main drivers of all human impacts
1. size of human population
2. per capita rate of consumption
3. environmental effects of the tech used
32
what is the role of conservation science
to determine how human disturbances are altering natural systems and predict future impacts by analyzing quantitative data
33
goals of conservation science
determine most effective conservation actions
| provide objective discussion of consequences and trade-offs
34
background rate of extinction
rate between periods of mass extinctions
35
deep roots of conservation
Aristotle (384-322BC)
King Philip IV, France (1268-1314)
Charles Darwin (1809-1882)
36
King Philip IV conservation
restricted types of traps, nets, and seasons for fishing in 1289 after realizing fishermen were decreasing the amount of fish in the rivers
37
Charles Darwin conservation views
scientific value: "the rescue and protection of these animals is recommended less on account of their utility.. than on account of the great scientific interest attached to them."
38
Important groups in 19th century American conservation
1. The Romantic-Transcendental conservation ethic
2. The resource conservation ethic
3. The evolutionary-ecological land ethic
39
Romantic-transcendental conservation
The Preservationists
Henry David Thoreau
John Muir
Ralph Waldo Emerson
40
Preservationist beliefs
nature feeds our soul, spiritual romantic values
41
Thoreau
1817-1862
| recognized and wrote about beauty of nature before people thought about or cared about it
42
Muir
1838-1941
activist
helped bring about preservation of Yosemite
43
Resource conservation ethic
The Conservationist
| Gifford Pinchot
44
Conservationist beliefs
utilitarian, we should protect nature for its resources
45
Evolutionary-Ecological Land ethic
Aldo Leopold
recognize the need to consider systems, and relationship between parts, ties beauty and usefulness together, lead to CB as we know it
46
Rachel Carson
1907-1964
Silent Spring
call to arms, led to precautionary principle
47
precautionary principle
we should not carry out actions that could be harmful to health/ environment if the effects are not fully established
48
Fundamental conservation biologists, 1960-1980s
Michael Soulé
Jane Goodall
EO Wilson
David Suzuki
49
why did conservation biology arise
- in 1980s ecologists were concerned about human impacts
| - inadequacy of existing disciplines
50
Conservation biology is made up of
```
biological science (ecology, evolution, genetics)
applied science (forestry, fisheries, agriculture)
physical science (climate, atmos, soil)
social science (economics, law, politics, ethics)
```
51
conservation biology is a mission-oriented science
focus on how to protect and restore biodiversity, diversity of life on earth
52
general questions conservation biologists must answer
1. how is diversity of life distributed
2. what threads does diversity face
3. what can be done to reduce/eliminate threats and restore diversity
53
Conservation Biology's ethical principals
1. Biodiversity should be preserved
2. evolution should continue
3. ecological complexity should be maintained
4. biological diversity has intrinsic value
5. people must be included in conservation planning
54
qualities of conservation biology
```
'crisis' discipline
largely reactive rather than pro-active
'mission-driven'
multi-disciplinary
encompasses all diversity
inexact science
evolution time-scale
```
55
Prevailing view of conservation through time
1960-70: nature for itself
1980-90: nature despite people
2000-05: nature for people
2010: nature and people
56
resilience
how much we can perturb the system before it switches to a new state
57
NCS
new conservation science
| needs of humans should be prioritized over intrinsic values
58
what is wrong with NCS claims
conservation already considers humans, is realistic, and has succeeded in the past
humans views change with time
59
Important conservation organizations
```
Audubon (1886)
Sierra Club (1892)
IUCN (1934)
Ducks Unlimited (1938)
The Nature Conservancy (1951)
WWF (1961)
Society for Conservation Biology (1985)
Conservation International (1987)
```
60
Conservation Landmarks
```
US Endangered Species Act (1973)
Rio Earth Summit (1992)
Kyoto Protocol (1997)
Species at risk act (2002)
Earth Summit (2012)
```
61
Conservation in Canada
```
Control of species consumption (1800s)
Banff National Park (1887)
Commission of Conservation (1909)
Point Pelee National Park (1919)
National Parks Act (1930)
COSEWIC (1977)
Canadian Biodiversity strategy (1995)
Species At Risk Act (2002)
```
62
Commission of Conservation, Canada
1909
| efficiency of natural resource use
63
Point Pelee National Park
1919
| focused on wildlife habitat (migratory birds) rather than commercial benefits
64
National Parks Acts
1930
| systematic protection from development
65
COSEWIC
Committee on the Status of Endangered Wildlife in Canada
66
What role does conservation science play in protecting biodiversity
- illuminates biodiversity patterns, threats, solutions
| - informs policy decisions
67
Policy decisions should
protect biodiversity based on economics, politics, societal values
68
Sciences key role in conservation
```
clarify:
effect of current activities
which actions are most effective
provide:
objective discussion
```
69
Pleistocene overkill hypothesis
widespread and catastrophic extinctions of large land-dwelling mammals to early human hunting
70
Where was Pleistocene overkill
Australia 40-70kya
NA 11kya
NZ 1kya
everywhere humans emigrated
71
extinctions 'known' to be directly from hunting
dod
stellar's sea cow
caribbean monk seal
passenger pigeon
72
functionally extinct
no longer serving the ecological role they once did
73
example of functionally extinct species
American Bison
74
Major habitats lost (>40%)
mediterranean woodlands
temperate grasslands
temperate broadleaf forests
75
Conservation in Canada has historically been
utilitarian
76
biodiversity
- variability among organisms and the ecological complexes they are part of
- diversity within species, between species, of ecosystems
77
compositional levels of biodiversity
genetic diversity
species diversity
community/ecosystems diversity
78
Hierarchical components of biodiversity
3 nested groups: compositional, structural, functional
79
structural component of biodiversity
genetic, population, habitat structure, landscape patterns
80
Compositional component of biodiversity
genes
species, populations
communities, ecosystems
landscape types
81
functional component of biodiversity
genetic processes
demographic processes, life histories
interspecific interaction, ecosystem processes
landscape processes, disturbances
82
components of biodiversity the public responds to the most
compositional - genes, species, populations, communities, ecosystems
83
fundamental unit of conservation
generally the species
84
biological species definition
a group of individuals that interbreed in the wild to produce viable, fertile, offspring
85
problem with biological species definition
some 'non-natural' groups breed and produce fertile offspring
ex. Red Wolf (maybe)
asexual producers
86
morphological species definition
morphologically, physiologically, biochemically distinct from other groups in some important characteristic
87
problems with morphological species definition
some species have huge variation (dogs, humans)
| cryptic species
88
phylogenetic species concept
because of relatedness share at least one morphological or molecular trait that is absent in other potentially related groups
89
problem with cryptic species
can mask threats to 1 species if 2+ are thought to be the same
90
Number of named species on Earth
ca. 2 million
| > 1.5 mill
91
number of species described per year
ca. 18,000/yr
92
How many species are there on Earth
3-30million
| best estimate ca. 5million ± 3
93
most specious taxa on earth
insects - estimated to be nearly 1 million
94
Lesula
a new species of monkey described in 2012 from congo
| even vertebrates are still being discovered
95
best described taxa on earth
Plantae! easy to see, don't move around
96
synonymy =
taxonomic inflation
97
taxonomic inflation
looks like there are more species than there are b/c some species are named more than ones
98
% of taxa likely to be synonyms
17. 9% species
| 7. 4% genus
99
why does synonymy occur
```
large range species
generalists
intra-specific variation
poor communication between scientists
few/poor reference collections
phenotypic plasticity
```
100
example of synonymy
European mussel
Anodonta cygnea
described 549 times!
101
species accumulation curve
```
# species vs # of samples
when graph starts to asymptote then getting close to the true number of species
```
102
most well known biodiversity pattern
biodiv inversely proportional to latitude
species increase towards equator
seen in amphibians, plants, fish, endemics, bivalves, corals, mangroves, seagrasses
103
where are endemic species highest
low latitudes
| islands, isolated ecosystems
104
general biodiversity patterns
1. Latitudinal diversity gradient
2. species-energy relationship
3. species-area relationship
105
latitudinal diversity gradient
species richness vs latitude
| parabola, increasing from -90 - 0, hump, decreasing from 0 -90º
106
species-energy relationship
sun --> energy --> PP --> more species
SR vs evapotranspiration
increasing power function
107
evapotranspiration
water transfer from soil to atmosphere by plant transpiration
proxy for productivity
108
species-area relationship
```
# species vs area
increasing exponential fn
more space = more complex relationships, more room for large animals
```
109
diversity and scales
relationships can vary based on scale
| local patterns may not reflect the larger scale pattern
110
result of species-area hypothesis
tropics are largest biome
| relates to latitudinal diversity gradients
111
results of species-climate stability hypothesis
tropics have more stable climate
| relates to latitudinal diversity gradient
112
results of species- climate harshness hypothesis
few species can tolerate cold
| relates to latitudinal diversity gradient
113
results of species energy hypothesis
tropics have greatest productivity
| relates to latitudinal diversity gradient
114
hypotheses that support latitudinal-diversity gradient
species-area Ho
species-climate stability Ho
Species-climate harshness Ho
Species-energy Ho
115
what is a stable habitat
- stable in physicochemical characteristic - temp, precipitation
- stable through time
116
why are tropics stable through time
low latitudes are less likely to be covered and 'reset' by glaciations
117
species diversity
number and relative frequencies of species in a given community
118
ways to describe species diversity
species richness
| species evenness
119
species evenness
equitability of abundance across species
120
why local diversity patterns may show increased diversity
addition of invasives
121
homogenization
biodiversity crisis is homogenizing the world because generalists and species with large ranges have the advantage
122
Three types of species diversity
Alpha diversity
Beta diversity
Gamma diversity
123
importance of diveristy
buffers attacks to survivability
| increases resilience
124
% polymorphic loci
a measure of genetic diversity
| ex. rats have very high genetic diversity - high resilience
125
Alpha diversity
species we find in one specific place
local, within
eg. Saanich Peninsula
126
Beta diversity
species we find in an entire region
within, larger scale
eg. VI
127
Gamma diversity
difference in species between two places
| eg. differences between Saanich Peninsula and Strathcona Park
128
focusing on species protection
may miss out on important environments, related organisms
129
units to protect
species, biome, ecoregion
130
ecoregion
large area characterized by similar mix of environmental conditions that contains relatively distinct flora and fauna
131
major ecoregion of the world
```
oceania realm
nootropic realm
afrotropic realm
antarctic realm
indo-malay realm
australasia realm
nearctic realm
palearctic realm
```
132
Major biomes of the world
```
tropical rain forest
tropical seasonal forest/ savannah
woodland/shrubland
temperate grassland/ desert
boreal forest
subtropic desert
temperate rain forest
temperate seasonal forest
tundra
alpine
polar ice cap
```
133
Large marine ecosystems
regions of ocean encompassing coastal areas out to edge of continental shelves
ca. 200,000 km2
134
large marine ecosystems are characterized by distinct
bathymetry
hydrography
productivity
tropically dependent populations
135
values of biodiversity
intrinsic value
| instrumental value
136
intrinsic value
biodiversity is valuable independent of its value to humans
| organisms have a right to survive
137
instrumental value
humans value of biodiversity
138
types of instrumental biodiversity value
```
Aesthetic, cultural, spiritual
Goods
water/air purification, flood control, pollination
recreational
education, informational
```
139
biodiversity goods uses
consumptive use
| productive use
140
what is consumptive use
goods used directly by local communities and invisible to GDP
hard to quantify, attach value to
eg. food, fiber, medicine, fuel
raw products, oxygen
141
productive use
value added goods, 'in the system', visible to GDP
| finished foods and material , sold in a market
142
problem with intrinsic value
difficult to convince people of!
143
bioprospecting
sample, extract, study, test, unstudied organisms (plants) for value
biological mining
144
plant species that have led to drug discoveries
1/125
145
% of pharmaceuticals based on organism products
79%
| based on plants, fungi, bacteria, verts
146
how many plant species have been examined for medicinal properties
less than 0.5%
147
examples of plants leading to medicinal discoveries
```
Willow (Salix spp) -- Acetylsalicylic acid
Pacific yew (Taxus brevifolia) -- Taxol cancer treatment
```
148
Ideas behind instrumental valuation of biodiversity
adding value to biodiversity in order to get people to 'buy in to conservation'
149
ecosystem services
essential goods, service, natural ecosystems deliver to people
150
Types of marine ecosystem services
Provisioning services
regulating devices
cultural services
supporting services
151
marine ecosystem provisioning services
seafood
timber, fiber
pharmaceuticals
152
marine ecosystem, regulating services
water quality control
| climate regulation
153
marine ecosystem, cultural services
tourism, recreation
| aesthetics, spiritual values
154
marine ecosystem, supporting services
nursery habitats
155
marine and terrestrial ecosystem link
Earth system, tightly linked, support each other
| eg. salmon - river- riparian - forest
156
habitat loss concerns
leading cause of extinctions/ endangerment
loss of beauty, rec, inspiration
important roles
157
what roles do habitats play
carbon sequestration
reduce flooding
storme surge protection
maintain soils
158
problems with invasive species
```
weeds
insect pests
vectors of disease
clog waterways
change fire frequency
alter ecosystem processes
global homogenization
```
159
changes in CO2
1960 - 280ppm
2013 - 395ppm
now - 0ver 400
increase 0.5-1% /yr
160
changes in world temperature
1951-2012 0.12ºC increase / decade
161
shifts in spring behaviours
2-3 day shift / decade
162
species range shifts
poleword 10km/ day
163
other climate change impacts
```
nitrogen cycle alteration
O3 depletion
acid rain
algal blooms
eutrophication
anoxia
```
164
anthropocene
an era in which anthropogenic impacts dominate
165
cryptic species effect on species number
if not recognized than species # lower
once recognized species # increased
recognized more now with DNA analysis
166
Largest extinction
P-T, 250Mya, formation of Pangaea, 96% of species lost
167
trait most strongly associated with extinction
body size
168
KT extinction
65Mya
dinosaur extinction
start of age of mammals
169
species at greatest risk
specialists - limited resources
| endemics - limited habitat
170
with accelerated extinction levels what should we expect to see in the future
small bodied, widespread, generalist species
171
hybridization occurs most
in endangered populations
| generally leads to lower fitness
172
insurance
biodiversity
173
negative externalities
environmental harm/damage from exploitation that impacts others who had no choice in the matter
174
problems with ES and negative externalities
human-centered, no biodiversity focus
can be seen as disingenuous
can backfire
175
what should we conserve
particular species, number of species, endemics, threatened species, number of ecosystems, threatened or special ecosystems, biodiversity hotspots, evolutionary uniqueness
176
biodiversity hotspots
>2500 endemic plant species
>70% loss of original habitat
eg madagascar
177
Madagascar
90% loss of rainforest
| 12,000 endemic plant species
178
problem with conserving hotspots
narrow focus on species richness and threat
whole ecosystems can be overlooked
ignores cost effectiveness and feasibility
spatial scale
179
incongruence
species richness, hotspots, endemism, threats do not always line up
180
some conservation frameworks
```
biodiversity hotspots
crisis ecoregion
endemic bird areas
megadiversity countries
WWFs global 200
high-biodiversity wild
frontier forests
last of the wild
```
181
aligning conservation frameworks
Irreplaceability vs. vulnerability
low vulnerability = proactive approach
high vulnerability = reactive approach
182
"Last of the Wild" conservation framework
Wildlife conservation society
areas with lowest human ecological footprint
less likely to obscure by conflicts and proposals of human infrastructure, may maintain status for long time
183
conservation funding
90% of the $6B of funding originates in and is spent in economically rich countries
ca. $600 million 'flexible' funds
184
prioritization schemes important for
justifying and obtaining funding
185
focal species
```
flagship species
umbrella species
indicator species
keystone species
dominant species
foundation species
ecosystem engineer
```
186
flagship species
'easy' to protect, special charismatic or cultural value
strategic concept for raising public awareness and financial support
often: large, ferocious, cuddly, cute
187
umbrella species
conservation of an organism protects a number of others, typically have large or unique habitat needs
188
Indicator species
most sensitive to perturbation or habitat-of-concern, canary in the coal mine
189
keystone species
species whose impact on its ecosystem is disproportionately large relative to its abundance
190
dominant species
species with large impact on ecosystem because of its high abundance
191
example of flagship species
panda
192
example of umbrella species
grizzly bear, if we seek to conserve their habitat it is a large area of forest that could also protect others like owls and even the plants
193
example of indicator species
owls
194
importance of indicator species
they tell us about the health of the ecosystem
195
keystone species example
sea otter - kelp - sea urchin
196
example of dominant species
bunny
| bison
197
foundation species
dominant autotrophs the rest of the ecosystem depends upon
198
foundation species example
kelp
pines
sea grass
mangroves
199
ecosystem engineer
species that modifies the habitat in a way that impacts others
200
example of ecosystem engineer
beaver
| elephant
201
example of evolutionary uniqueness
Tuatara
202
other protection units
unique biological processes (ex monarchs)
| migratory routes
203
what to protect if focused on ecosystem function
the ecosystem, some % of species everywhere, not focus on biodiversity or certain species
204
what factor is consistently overlooked in conservation prioritization
COST
feasibility
return on investment
205
cost
-purchase
-management
costs can vary more than diversity
206
feasibility
governance, law and order, corruption
peace
capacity (literacy, education)
207
Wildlife Conservation Societies 'global priority species'
```
broad geographic range
evolutionarily distinctive
ecologically important
important to humans
need conservation action
```
208
prioritization schemes typically based upon
some measures of biodiversity and threat often in a framework of vulnerability and irreplaceability, may be be proactive or reactive, individual and subjective
209
prioritization scheme pro
proven useful in mobilizing funding
210
prioritization scheme con
do not make best use of conservation $$, do not factor in ROI (return on investment)
211
to maximize conservation success
biological factors, cost, and feasibility must be taken into account
212
globally extinct
no individuals remain anywhere in the world
213
extinct in the wild
individuals of the species occur only in captivity
| at least 68 spp
214
regional/local extinction
loss of species from part of its former geographic range
215
extirpation
purposeful disappearance (often wrongly used to mean local extinction)
216
example of extirpation
basking shark
| sea otter
217
impact of local extinctions
often lead to global extinctions
can cause extinction of other species in ecosystem
species are interconnected
218
why to be concerned about local extinctions
populations are unique (genetically, behaviourally, morphologically)
impacts and management often occur at population scale
disappearance of populations precedes global extinction
219
more subspecies =
higher chance of species survival
220
co-extinction
an extinction that occurs alongside extinction of a focal species
221
co-extinctions most commonly in
specialist parasites
| ex. passenger pigeon louse, tropical butterfly and host plants
222
ecological / functional extinction
the reduction of a species to such low abundance that it no longer interacts significantly with other species or performs its ecosystem function
223
proving extinction
very difficult, easy to miss, require exhaustive surveying, can get it wrong
224
possibly extinct
likely but a chance they are extant
225
Lazarus effect / Romeo error
declared extinct when they actually aren't
226
why does lazarus effects occur
not enough money for in depth survey
| difficult to find every last individual
227
example of lazarus effect
Cebu flowerpecker declared extinct in 1950s, found in 1992 (86 yrs with no record!)
228
when are extinctions typically discovered
long after, often >75yrs
| few species with every individual monitored
229
other problem with extinctions
many go unnoticed, especially small, inconspicuous species
230
number of species extinction per year
ca. 27,000
74/yr
3/hour
EO Wilson
231
commercial extinction
overexploitation of a target species to the point that it is so low and sparse that it is no longer worth targeting, often assumed safe from biological extinction but often not
232
examples of commercial extinction
bluefin tuna
abelone
atlantic cod
233
species average lifespan
1-10MY
234
example of ecological extinction
oysters in Chesapeake bay, population overexploited, reduced water filtering potential
235
what is the background extinction rate
0.1-1 species/ million species / year
236
current best estimate of # of species on earth
ca. 10M
237
what would background extinction be now based on best estimate of number of species on earth
1-10 species / year
238
current actual extinction rate
100 (known) extinctions / 210000 species / 100 years
1 ext. / 21,000 species / yr
47.6 ext. / mill species / yr
ca. 50-500X the background rate
239
ecosystem services
essential goods and services ranging from medicines and building materials to soils, water, flood control, that natural ecosystems deliver to ppl
240
MEA
Millenium Ecosystem Assessment (2005)
1300 scientists, 95 countries determine that humans interfere on such a huge scale that human well-being is at risk, and the ppl most at risk are the rural poor
241
protect natural vegetation?
may not be high biodiversity but may protect ecosystems and decrease catastrophes, loss of marshes exacerbated the effects of Katrina
242
rivot hypothesis
a few losses will not impact the system but many losses will result in loss of function
243
portfolio effect
stability-diversity relationship, diversified portfolio so that gains can offset the losses -- net stability
244
portfolio effect in a single species
plasticity of subpopulations
245
why do people degrade the environment
economic incentive
246
economic valuation
assigning value of services and their negative externalities to make degradation more apparent, may increase sustainability decisions, difficult to assess
247
willingness to pay
maximum stated price an individual would pay to avoid loss or reduction of ES
248
PES
Payments for Ecosystem Services
| reward land owners for conserving/ restoring ES
249
example of PES
water funds
| grains to green program
250
serviceshed
area where an ecosystem service is generated and where people benefit from it
251
InVEST
Integrated Valuation of Environmental Service and Tradeoffs
| map services, provide quantitative data to help conservationists compare areas/efforts and make decisions
252
conservation market
if a market exists, conservation will result in benefits for biodiversity and economics
ex. carbon sequestration, reforestation
253
Is ES approach the right way to go
may undervalue intrinsic values
| best approach incorporates ES + regulations + ethical appeal
254
marine species extinctions
18 marine species listed as extinct on IUCN 2013 list
| no known fish -too difficult to document
255
Great auk
flightless, islander
| Atlantic, last known from 1852
256
extinction debt
habitat destruction compromises species range, not resulting in complete and immediate extinction, but eventual extinction;
extinctions occur generations after fragmentation;
future ecological cost of current habitat destruction
257
Time lag
individuals persist for long periods of time in lower quality habitat fragments, populations slowly spiral to extinction
258
most threatened taxa
```
% threatened
gymnosperms - 36%
fishes - 37%
reptiles - 31%
amphibians - 30%
```
259
Vulnerability to extinction
```
V = ES
vulnerability = extrinsic threatening process x intrinsic sensitivity
```
260
Main correlates of extinction
1. Large body size
2. Small geographic range
3. Specialization
261
body size and extinction
low intrinsic rate of pop increase
high trophic level
smaller pop size
262
intrinsic rate of increase
rate a population increases in size if there are no density-dependent forces regulating the population, births - death per generation
263
small geographic range and extinction
island populations
mountain/ peninsula species
single location endemics
264
why do islands have large number of endemics
evolutionary isolation
265
examples of island extinctions
Stephen's island wren, NZ
| 17 extinct lemurs, Madagascar
266
specialization and extinction, ecological specialism
```
Habitat specialization
Diet specialization
ex. panda bear
Diadromy
Flightlessness
```
267
diadromy
migration of fish in either direction, from fresh to sea water reverse
268
examples of diadromy
salmon
eels
sturgeons
269
total abundance vs index of specialization
exponential increase
| generalists >> abundance than specialists
270
NZ Moa
10-11 species of flightless endemic bird
died 700-400BP
co-extinction with Haast's eagle
271
why model
nature is complex (simplify)
models help clarify our thinking (understand)
models generate testable predictions (forecast)
models provide insight into the systems they mimic
272
problem with models
abstract representations, not always accurate,
| nature doesn't have to follow natures, do not rely to heavily on them
273
Why is EO Wilson's extinction rate so high
extinctions are very slow, not all known
274
Estimating extinction risk
read species area curve backwards
275
species area curve function
```
S = c A^z
S = species
c = constant
A = area
z = rate of species accumulation
```
276
number of biodiversity hotspots
25
277
CRI
conservation risk index
| fraction of habitat protected : fraction of habitat converted
278
unique habitats not protected if only focused on biodiversity
Yellowstone
Hydrothermal vents
marshes
279
Conservation planning process
1. ID conservation target
2. Inventory region for targets and threats
3. Set conservation goals
4. Design network of conservation areas
280
Conservation goals
specific, measurable, quantifiable, needed to measure success, adjustable
how much is needed to sustain population
281
important to include in planning
costs
objectives
species shifts
282
ES vs biodiversity
not correlated but should try to find sites that rank high for both
283
example of including multiple priorities in conservation plan
Florida - planned to reduce storm surge, included important habitat, areas of flood risk, vulnerable human population, threatened/ endangered species
284
species lost at 50% habitat loss
10% species loss
285
species lost at 90% habitat loss
50% species loss
286
If we lose half the area of an island, what proportion of species do we expect to lose (assuming c = 4, z = 0.2)
S = cA^z
| 12%
287
% species lost with 50% habitat destroyed vs z
increasing
| higher z = higher species losses
288
Singapore species loss
95% of forest lost over 180 years
30% loss of forest species
32% of native birds lost
289
Assumptions of SAC estimates
1. habitat loss instantaneously eliminates species
2. habitats are lost (in reality often converted)
3. Habitat loss is random with respect to SR / habitat quality
4. Individual vs. the whole
5. extinction rates are unaffected by fragmentation of remaining habitat
6. other threats
290
why does S-A approach consistently overestimate the actual rate of extinction
space that must be searched to find single individual of species smaller than space that has to be searched to find every last individual of that species - going backwards is not the same as going forwards
291
why are marine ecoregion based on seafloor environment
species distribution is challenging to map and knowledge is limited compared to land
292
biodiversity offsets
form of mitigation in which loss of biodiversity at one site is compensated for (offset) by protecting another area
293
common conservation mistakes
- not labelling plan as prioritization
- too vague of definitions
- too much attention to places over actions
- arbitrary indices
- not incorporating risk of failure
294
z is SAC depends on
isolation, connectivity, migration / movements
| high isolation = large z
295
small populations =
larger extinction threat
296
IUCN
International union for conservation of nature;
| only official global list of species at risk; 8 categories
297
IUCN Categories
```
Extinct
extinct in the wild
critically endangered
endangered
vulnerable
near threatened
least concern
```
298
extinction vortex
extrinsic factors -- population shrink -- small, isolated population, inbreeding and drift reduce genetic variability and individual fitness -- population declines -- demographic / environmental stochasticity, allee effect -- reduced population -- repeat downward spiral --
299
extrinsic factors that shrink population
habitat destruction
pollution
over harvest
invasive species
300
overall extinction vortex pattern
small pop -- low genetic variability -- lower survival, lower reproduction -- small pop -- downward spiral to extinction
301
Allee effect
correlation between pop size/density and mean individual fitness
302
demographic stochasticity
variability of pop growth rates arising from related random events
ex. birth rates, death rates, sex ratio, dispersal
303
environmental stochasticity
unpredictable fluctuations in environment conditions; one of main sources of fluctuation in ecological processes; cause pop fluctuations
304
inbreeding =
increased homozygosity = reduced fitness
305
effects of fragmentation, Chiew Lam reservoir
native smal mammals disappeared rapidly, after 25 yrs small mammals almost gone from 16 islands, SR most correlated to area
306
modeling population change over time
BIDE
307
BIDE
N_t+1 = N_t + Births + Immigrants - Deaths - Emigrants
308
modelling discrete population growth
exponential growth, closed population, BR/DR constant, growth by same factor each year- not truly continuous
309
discrete population growth function
N_t+1 = N_t *λ
310
discrete population growth rate, λ =
N_t+1 / N_t
311
exponential population growth beyond one year
N_t = N_o * λ^t
λ = (N_t /
N_o) ^ 1/t
312
effect of λ on population growth
λ > 1 - population growth is exponential
λ = 1, pop is stable
λ less than 1, pop declines
313
continuous population growth
```
dN/dt = (b-d)N
dN/dt = rN
Nt = N_o *e^rt
```
314
r
per capita intrinsic rate of increase
r > 0, pop increases exponentially
r = 0, pop constant
r less than 0, pop decreases exponentially
315
Doubling time
a population growing exponentially has a constant doubling time
316
t_d =
ln2/r
317
λ =
e^r
318
r =
ln(λ)
319
advantages of λ
technically more accurate for discretely growing pop's; can be intuitive; translates easily into % annual growth
320
If λ = 1.20
population growing at 20% / yr
321
advantages of r
entered around 0 (symmetric)
| **Scales
322
inbreeding
increases frequency of deleterious alleles
323
what happens when capital is drawn down
no buffer
324
exponential population growth assumptions
```
population closed (NO I, E)
constant B/D rates; deterministic
No age or size structure
```
325
Allee effects
survival and reproductive success of each individual declines in a deterministic manner as pop. declines; at low density pop growth is hindered; individuals benefit from having conspecifics
326
deterministic system
system in which no randomness is involved in the development of future states of the system
327
Allee effects: mechanisms
minimize predation
foraging advantage
reproductive success
conditioning of environment
328
how allee effect minimizes predation
detection and defense
predator swamping
anti-predator aggression
329
how allee effect creates foraging advantage
access to food
social hunters
cooperative resources defense
330
how allee effect increases reproductive success
obligate cooperative breeders
| finding mates
331
why are rare alleles less likely to be expressed
more often present as heterozygotes, inbreeding increases homozygosity
332
species area overestimates extinction how much
estimated rates nearly double actual rate
333
results of sea turtle functional extinction
ecological collapse of seagrass beds
334
red listed species
vulnerable - high risk
endangered - very high risk
critically endangered - extremely high risk
335
density independent population change
pop shrinks or grows at a constant rate regardless of how sparse or crowded it becomes, i.e. resources are unlimited no matter how large and no problems finding mates/ resources when pop shrinks
336
deterministic population dynamics
there are no 'good years' and 'bad years', environment is constant (resource availability, predation, disease, disturbance), i.e. no environmental stochasticity
337
homogeneous individuals
all individuals have same reproductive success and same probability of survival and growth (i.e. no demographic stochasticity)
338
If a population grows by 30% (λ=1.3) one year and shrinks by 30% (λ=0.7) the next year
does not sum up to net = o
λ = 1.3 of No =100 results in 130
λ = 0.7 of No =130 results in Nt = 91
overall λ = 0.95, geometric mean (GM)
339
GM =
square root (product of λ_i's)
340
stochasticity
randomness or uncertainty
341
demographic stochasticity
if a pop has few individuals chance variations in the sex ratio of offspring or the survival and reproductive success of individuals can prevail over what is expected on average
342
positive correlation between population size and individual success
allee effect
343
impact of geographic range on environmental stochasticity
smal range = higher chance of entire species being wiped out by one event
