Biodiversity Threats
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Transcript Biodiversity Threats
© Sam Ferreira
Global Patterns
Unsustainable exploitation
of biodiversity
Rands et al. 2010. Science 329: 1298-1303
End of the line – imagine a
world without fish
www.endofthelinemovie.com
Large mammal declines in
parks
Craigie et al. 2010. Biological Conservation 123: 45-54
© Sam Ferreira
Large Mammal Populations
South Africa may do better sometimes
100%
80%
60%
40%
Unknown
Decrease
Stable
20%
Increase
0%
54% increasing or stable
4% decreasing
Ferreira et al. 2009. SANParks, South Africa
The Business of Ecosystem Services
• Carbon sequestration
• Community-based ecotourism
• Resource use
– Harvesting
– Hunting
– Water quality
© Rudi van Aarde
Increased monetary-based values
A conflict of interest for conservationists?
• Biodiversity degrades with monetary-based approaches
• Conundrum for protected areas
• Protect biodiversity
• But also generate revenue
Mills & Waite 2009. Ecological Economics 68: 2087-2095
© Sam Ferreira
© Rudi van Aarde
Why is biodiversity important?
• It has livelihood links
– Monetary
– Non-monetary
• Threats to biodiversity threatens livelihoods
© Adrian Shrader
Threats are drivers of Global Environmental Change
Reduction or Loss of Species in Protected Areas
22%
Habitat Change
Fire, prescribed burning,
elephant damage,
habitat loss and quality,
starvation, declining resources
3%
Climate Change
6%
Invasive species
Drought
Fish stocking,
bush encroachment
3%
Pollution
25%
Over-Exploitation
Hunting,
removals for translocation
13%
Disease
Affects resource availability
10%
Predation
13%
Unknown
54 % of cases involved more than one driver
Gaston et al. 2008. Annual Review of Ecology, Evolution and Systematics 39: 93-113
Climate Change as a Driver
Ocean acidification
• Since 1970 pH dropped by 0.1
Sea-level rise
• Cost 5-10% GDP
Africa
• 75-250 million people water stress by 2020
• Rural agricultural yield drop by 50% by 2020
• 5-8% more arid land by 2080
Intergovernmental Panel on Climate Change (IPPC): 4th Report 2007
Biodiversity consequences of Climate Change
Plants on the move
7
Upper altitudinal boundary
contracted downslope
Upper altitudinal boundary
expanded upslope
Number of species
Number of species
6
5
Moving upslope
Moving downslope
43%
Ave. = 69m
4
3
2
1
0
-100
-80
-60
-40
-20
0
20
40
60
80
100
Upslope shift (m)
Altitudinal shift (m)
Le Roux & McGeoch 2008. Global Change Biology 14: 2950-2962
Invasive Species as a Driver
Invasive alien plants in Kruger
Foxcroft & Richardson 2003. In Plant invasives. Blackhyus Publishers.
Aerial extent of Opuntia stricta
Foxcroft et al. 2004. Diversity and Distribution 10: 427-437
© Sam Ferreira
Biodiversity consequences of Invasive Species
Impact of the Argentine ant on native Fynbos ants
Invaded
Not invaded
Richness
21.39 ± 2.31
35.56 ± 2.32*
Abundance
67.49 ± 18.87
19.49 ± 18.88*
Homogenization
0.008 ± 0.002
0.77 ± 0.002**
McGeoch, Unpublished data
© Melodie McGeogh
Over-exploitation as a Driver
What does it mean?
Conceptual driver
Populations harvested unsustainably
Tragedy of the commons
- Reproduction cannot compensate for mortalities
- Increase of individual resources
- e.g. herd of cows
- Detriment of common resources
- e.g. communal fodder
Wilcove et al. 1998. BioScience 48: 607-615
- Resource quality change
Food and Agriculture Organization of the
United Nations 2007
Hardin 1968. Science 162: 1243-1248
Frank et al. 2005. Science 308: 1621–1623
Pollution as a Driver
State of South Africa’s River Systems
Dissolved inorganic nitrogen
NO3- + NO2
18/25 cases, 7**
Fertilizer use
Time
Phosphorous
PO43
23/25 cases, 14**
Effluent
Time
deVilliers & Thiart 2007. South African Journal of Science 103: 343-349
© Melodie McGeogh
Biodiversity consequences of Pollution
Helicopter
Spotlight
Dead
28
2000
1000
0
May
Jun
July
Aug
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Dead
170
Number of crocodiles
3000
2008/2009
2009/2010
Ferreira & Pienaar 2010. Aquatic Conservation Submitted
© Andrew Deacon
Disease as a Driver
Emerging infectious disease
Transfer between domestic animals and wildlife
Daszak et al. 2000. Science 287: 443-449
Human translocation of hosts and parasites
Spear & Chown 2008. Journal of Biogeography
No human or domestic animal involvement
Matthee et al. 2004. Journal of Parasitology 90: 1263-1273
Consequences
Direct threat to wildlife
Indirect threat via human antagonism
impact
Wildlife
Plants & animals
translocation
Homogenization
Mixing
Loss of diversity
Increase in EIDs
Increased risk of disease
and disease transfer
Belden & Harris 2007. Frontiers in Ecology and the Environment 5: 533-539
© Danny Govender
Habitat Change as a Driver
Management actions
fire
herbivory
soil
Tree
Grass
Dynamics
rainfall
[CO2]
Climate change
Bond 2008. Annual Review of Ecology and Systematics 39: 641-659
Habitat clearing
Vehicle numbers
Fragmentation
Tourism facilities
Roads
Tourist numbers
© Sam Ferreira
Dealing with threats
Essentially a social problem
growth of human populations
per capita consumption
Rands et al. 2010. Science 329: 1298-1303
Climate change
Invasive species
Over-exploitation
Pollution
Disease
Habitat change
– land expansion
– regulatory and restoration
– regulatory and restoration
– regulatory and restoration
– regulatory and scenarios
– protection and restoration
Diversify approaches
• Integrate conservation friendly land-uses
• Socio-economic-ecological complexity
• Conservationists are negotiators
MISSION
To manage Golden Gate Highlands National
Park in a collaborative learning environment
as part of an ecologically functional and
sustainable patchwork of different land uses
in the region that ensures the persistence of
the natural and cultural heritage for the
benefit and enjoyment of all.
SANParks 2009. Pretoria.
Scenario Planning
Consequences often unknown
Nearly all drivers fall in this category
Disease accentuated
Medical examples to embrace
http://www.physorg.com/news160327953.html
© Markus Hofmeyr
Make links and manage causal mechanisms
Objectives
and
outcomes
Drivers and indicators
Mechanisms and modulators
- impacts on biodiversity
- tall trees
- aesthetics
- conflict
- how they use space
- water directly modulates
- density may override this
Management responses
Monitoring needs
Objectives
Ecosystem
Abiotic – soil nutrients
Decomposers – millipedes
Producers – vegetation
Consumers – birds
Species of Concern
Rare species
Endemic species
Stakeholders
Perceptions
Complaints
Tourists
Satisfaction
Revisits
Drivers and indicators
Mechanisms and modulators
Elephants
Patch density
Fragstats
Large trees
Size distribution
Elephants
Home range overlap
Season distribution
Stakeholders
Wildlife conflict
Damage to crops
Mammals
Sightings
Diversity
Tourist effort
Restore space
Manipulate resource
Exclude resource
Rotate resource
Exclude impact
Induce predation
Induce dispersal
Mimic predation
Mimic dispersal
Manipulate births
Manipulate deaths
Direct modulator
Water availability
Fence distribution
Indirect modulator
Abundance
Density
Humans
Landscape use
Gaylard & Ferreira 2010. Koedoe. Submitted
Our legacy?
• Biodiversity begets livelihoods
• Livelihoods threaten biodiversity
• The Year of Biodiversity - A way of living
– matrix of different land-uses
Ferreira et al. 2010. Journal of Environmental Management Submitted
– biodiversity is global public good
– integrate biodiversity
• resource production
• consumption
– wider institutional and societal changes
– enable effective implementation
Rands et al. 2010. Science 329: 1298-1303
© Sam Ferreira
Biodiversity should be an accidental
outcome of sustainable livelihoods
© Rudi van Aarde