Conservation Flashcards
(34 cards)
Human-caused extinction
Different from ‘background’ extinction rates that are part of the evolutionary process
Affecting more species at a much faster rate
Conservation is predominantly about preventing extinctions caused by humans
Locally extinct
Extinct from part of its range, but still exists elsewhere
Functionally extinct
No longer enough individuals present to fulfill their role in the ecosystem
Co-extinction
When the loss of one species leads to the loss of another
Endling
The last living individual of a species
Lazarus effect
When a species is thought extinct, but rediscovered
Vesk’s plant louse:
a co-extinction risk
Named after UniMelb ecologist Peter Vesk
Lives in the biodiversity hotspot of the Sterling Ranges, WA
Only feeds on the sap of the wattle Acacia veronica
Both are in decline
Benjamin the Tasmanian Tiger
Died in Hobart Zoo
September 7th 1936
Now memorialized as
“Threatened Species Day”
Once thought
extinct”
39 of Australia’s threatened species only occur in cities
12 “thought extinct” at some point
Often because we built houses over the last known site
Still threatened by the same processes
How does extinction happen
Extinction happens by affecting population dynamics
Population
‘viability’
The ability of a population to ‘persist’ – to survive through time
Also referred to as persistence
Population Viability Analysis (PVA)
Common approach that drives conservation
Determines the likelihood that a population will go extinct within a certain period of time
Can compare different scenarios
Change in vital rates
Effect of threats
Effect of conservation action
Population viability closely linked to size
Smaller populations = greater risk of extinction
Big changes to the Australian environment
Colonisation led to sudden (relatively) and dramatic change in the environment
Disrupted existing management by Indigenous people
Widespread clearing for settlement, agriculture and grazing
Introduction of new species into the system
Extensive persecution of many native species
Dams, concreted or covered waterways
Attempts to ‘tame’ the landscape
Australia’s extinction record
~100 species extinct since colonization
Probably more
Worst mammal extinction rate of any country in the world
35% of all modern mammal extinctions worldwide
More than 1800 species on our federal threatened species
list
Christmas Island Pippistrelle
1900-wide spread 1994- concern about the decline 2001-Endangered 2004-intensive monitoring began 2005-80% population decline 2006-Critically Endangered Recommend immediate captive breeding
3 years later…
January 2009
Fewer than 20 individuals left
Scientists: “Hey, we should really, REALLY do captive breeding”
February 2009
Government: “OK, we’ll do a trial on a different species and set up an expert working group”
Expert working group recommended captive breeding
July 2009
Government: “OK, OK, let’s do captive breeding”
August 2009
Only one pipistrelle was heard during surveys
It was never captured
And after August 26th it was never heard again
Preventing extinction
Research
Understand the species ecology, threats and actions
Monitoring
Be aware of its status and potential decline
Action
Do something!
Leadership
A champion for the species
Accountability
Must be responsible for decisions to save the species and be accountable for
these decisions (or lack thereof)
Why conserve biodiversity?
1. Utilitarian vBenefits to people vE.g. ecosystem services, clean water, clean air, food and medicinal value 2. Inherent vNature for nature’s sake vE.g. species have a right to exist
What are we conserving?
Biodiversity consists of all living things at all levels of organization and all of their interactions
This means conservation might focus on the:
1. Genetic level – genetic traits that allow species to adapt to environments, resist disease
2. Species level – the number and types of species
3. Ecosystem level – entire communities of species, their physical environment and the interactions between them.
Two broad types of conservation action
In situ Conserving the species in their habitat. - Habitat protection - Habitat restoration and enhancement - Removing threats - Behaviour change Ex situ Conserving the species away from their habitat - Captive breeding - Insurance populations - Gene banking - Zoos and botanic gardens
Which approach to use?
First protect species in their natural range (in situ) When might we add ex-situ? - Population is becoming too small - We don’t know why it is declining - The risks to the population cannot be mitigated
How does biology help us conserve species?
- Understand the species’ needs
- Understand the threats
- Understand the possible actions
- Understand the benefits of those actions
How do people fit in the story
Conservation action affects people
Conservation action is driven by people
People bring new knowledge to conservation practice
Conservation affects people
Benefits • Connection to nature • Health and well being • Ecosystem services • Tourism and resources Costs • Loss of income or access to land • Human-wildlife conflict • Loss of a resource • Loss of culture and traditions conservation should be built to masimise benefit and minise cost
Grey-headed
flying fox
Endangered
Increasingly found in cities along the east coast
Source of enormous conflict due to smell and droppping
Currently no solution
