Wildlife Conservation Flashcards
Examples of ecological catastrophes
- Dramatic reduction in number of insects
- Permafrost melting
- Wildfires becoming extensive beyond historical range
- Great pacific garbage patch
Bio-magnification
toxin is magnified the further up the food chain you go
Why do we need to estimate population sizes?
- Evaluation of status
- Changes in status
- Effectiveness of management strategies
- Almost all decisions in population management require information on population size and density
Things to consider when estimating population
- Is an absolute number needed, or is an index okay?
- Do I need a rough or accurate estimate?
- Is a measure of density important?
- What method is appropriate?
- Cost?
- Opportunity cost?
- Ethical consideration?
Direct counts of population estimate
- Observations
- Counts of quadrats, driving transects, spotlighting, camera traps, etc.
- Checking nest boxes
- Trapping
indirect counts of population size
- sand pads
- diggings
- scats
- hair tubes
- calls
- nest box use
- genetic ID of individuals
Schnabel formula
N = total (Ct/Mt) / total (Rt)
Mt = total number of previously marked animals at time t
Ct = number of caught animals at time t
Rt = number of marked animals caught at time t
Assumptions of Schnabel method
- closed population (dispersal barriers, slow reproductive rate, slow mortality rate)
- Equal trap-ability
- marks do not influence mortality or trap-ability
- independent sampling
- no marks are lost
Methods of marking animals for survey
- paint
- ear tags
- ear notching system
- passive implant transponders (PIT)
- leg bands (birds)
- tow clipping
- tattoos
- use of natural variation
Transects
- Covers large areas
- Suitable for species with large home range
- Relative estimates of abundance
- Detect movement between habitats
- Random or systematic placement is important
- Sampling lines must be parallel to gradient
Quadrats
- Cover smaller area
- Can target particular habitat type
- Provides estimate of abundance or density
- Systematic or random spacing may result in some habitats/areas being missed entirely
- Measure of density (D = n/a)
Considering spacing of survey technique
- Distance apart is important (far enough to sample home ranges of numerous animals, close enough so each home range can be sampled)
- Wide spacing may underestimate density
- Ideal sample spacing depends on population density and size of home range
Types of traps
- Cage
- Elliot
- Pitfall
- Funnel
- Leg-hold
Trapping considerations
- Trap spacing
- Number of traps
- Duration of trapping
- Local placement
- Bait
- Odor (re-use of unwashed traps)
- Local placement - stability of trap
Invertebrate population decline
45% decrease over the past 40 years
Causes of invertebrate decline
- Habitat clearing
- Pesticide use
- climate change
Why is invertebrate conservation so important?
- Pollination services
- Population control (controls invasive insects)
- nutrient recycling
- critical link in the food chain
Thermal fertility limit
in invertebrates it is 1.15 degrees lower than critical thermal limit (where they die) - invertebrates will become infertile in heatwaves
What is population viability analysis (pva)
- essentially a quantitative ‘risk assessment’ for the future that is species-specific
- estimates the likelihood of species extinction
- estimates the minimum viable population size (for population to be self-sustaining)
What is PVA based on
models that relate a dependent variable (population size) to the independent variables that influence it (e.g. weather, mortality, disease)
Stochastic events that affect population parameters in PVA
- Extrinsic – environmental uncertainty; natural catastrophe
- Intrinsic – demographic influences (e.g. fecundity, mortality); genetic influences (e.g. inbreeding, variability)
What is quasi-extinction
the number of individuals below which the population is likely to be critically imperiled (known as the MVP size for PVA)
What is an invasive species
introduced species (non-native) that have a tendency to spread in the new area to a degree that causes damage to the environment, economy, and/or health
What is an introduced species
species that are not native to an area and reached that area by accidental or deliberate human activity
Attributes of invasive species
- Rapid reproduction
- Rapid generation times
- Large clutch size
- Rapid development
- Low age at maturity
What are the 4 invasive species considered an extreme threat to native wildlife in Australia
- Cane toad
- feral cat
- fox
- feral pig
Invasive species case study: brown snake
- accidentally introduced to Guam in 1950s
- became extremely abundant as they were freed from population limiting factors present in native range
- now more than 2 million snakes in an isolated ecological community
- dangerous threat to ecology and economy of Guam
Impacts of invasive brown snake to Guam
- 10/13 of forest dwelling bird species went extinct
- Secondary effect: population explosion of bird prey > crop predation by insect pests > Dengue fever spread (human impact)
- after it ate all the birds, prey switching to native reptile occurred (6/12 have disappeared)
- changed forest composition (killing birds > less seed dispersal)
- costs $4 million annually
- no end in sight
How do we manage impact of invasive species
- predator proof fencing
- baiting
- quarantine
- public awareness
- ‘training’ affected species to learn what predator looks like and how to respond
- research to understand interactions and impacts
- monitoring management outcomes ciritcal
what is a boom in ecology
major, rapid population increase linked to resource availability
what is a bust in ecology
major, rapid population decrease linked to resource avilabilty
Boom and bust species example: Pied slit
reliant on brine shrimp for reproduction. Only breed when there is enough rain to fill ephemeral lake for presence of brine shrimp
How does fire affect flora
- kills tissues and individuals
- boosts nutrient cycling, changes soil properties
- alters population structure
- overcomes dormancy, stimulates seed release, germination and flowering
How does fire affect fauna
- kills individuals
- changes food resources (nectar, browsing, grazing)
- changes abiotic environment (thermal environment, i.e. shade)
- changes habitat elements (vegetation cover, litter cover, tree hollows, etc.)
Aspects of fire behavior
- intensity
- flame height
- crown vs understorey
- rate of spread
- embers/spotting
- fire driven weather (Pyro-cumulonimbus)
A fire regime must account for
- frequency
- season
- intensity (energy produced, fuel consumed)
- severity
- spatial attributes (patch and landscape mosaic)
- type (canopy, ground, etc)
plant response to fire (traits)
- life history/growth form (annuals, ephemerals, etc.)
- re-sprouting
- post-fire flowering
- post-fire recruitment
- seed persistence
- seed dormancy and germination
- long distance seed dispersal
- tolerable fire intervals
characteristics of islands
- Large dispersal barriers
- Make up a large % of earths Biodiversity hotspots
- New islands – provide unoccupied niches for species to fill and adapt to
- High levels of endemism, low levels of genetic diversity
- Varying degrees of isolation
- After colonizing, species may evolve in the absence of certain competitors/predators = ‘radiations’
Why are island species more prone to extinction
- Evolved features (species poor communities, predator and competitor absence)
- Generally small populations
- Area-limited (refuge areas small, introduced species can ‘invade’ all habitat faster)
- Prone to bottlenecks and genetic drift
why use islands as ‘arks’
- management option for species
- threats on mainland currently not managed or able to be managed in the near future
- islands mitigate extinction risk
- predator eradication more feasible
risks of using islands as ‘arks’
- more risky (weather, etc.)
- limited population growth
- prevents progressive mainland work (loss of urgency)
- ethics
- climate change refugees - sea level rise
Indigenous ranger program
- first funded by government in 2007
- working on country scheme
- 2100 jobs
- 123 ranger groups across Australia
Indigenous protected areas (IPAs)
Areas of Indigenous-owned land and/or sea country where traditional owners have entered into an agreement with the Australian Government to promote biodiversity and cultural resource conservation
benefits of incorporating indigenous ecological knowledge (IEK) into research
- Thousands of years of ecological knowledge
- As well as modern observations through connection to Country
- Provides link between ecology and culture
- Knowledge of remote regions unknown to Western Science
problem with land being used for grazing in Australia
- Not locally adapted
- Land degradation
- High water demand
- Methane output
- Native species displacement
how much of global land area is used for livestock grazing
26% (as of 2012)
Species of Kangaroo’s used for harvesting in Australua
- Western Grey
- Common Wallaroo
- Red Kangaroo
- Eastern Grey
Quotas set by government for kangaroo harvesting
- Based on prior years population estimates
- Harvest levels of 15-20% considered sustainable
- Set at or below these rates independently of industry demand
why is kangaroo harvesting sustainable
- Based in a sound understanding of kangaroo ecology
- Quota limit is variable according to environmental conditions, not set (facilitates natural population fluctuation)
- Population size post-harvest is heavily monitored
advantages of kangaroo harvesting
- ‘natural’ grazing pressure
- Lower soil compaction (soft padded animal)
- Low fat (< 2%) - healthier meat
- Better adapted to arid conditions
- Kangaroo are foregut fermenters and produce negligible amounts of GHG emissions
disadvantages of kangaroo harvesting
- Strong animal welfare lobby opposed to use of wildlife
- Lack of infrastructure
- Low consumer demand
- Low prices
What are fisheries
The interaction of fish with fishing gear, deployed by fishers at certain locations and times (called fishing effort), and resulting in catches
What is the aim of the Sea Around Us initiative
Research/communicate the effects of fishing on marine ecosystems of the world with a focus on long-term, ecological sustainability of fisheries resources
why do we need catch data when working on fisheries?
- To understand the size of the fishery
- To determine the value of the fishery
- Magnitude of environmental impacts
What are worldviews defined by
Ontologies (what exists in the world) and Epistemologies (knowledge of that world)
What are some different world views
- Western science
- Indigenous knowledge
Why restoration
- Loss of ecosystem function/services
- Trophic cascades – e.g. wolves in Yellowstone
- Sustainable species management
What are the three C’s of rewilding
Cored, Corridors and Carnivores
What is rewilding
Scientific argument for restoring big wilderness based on the regulatory role of large predators
Example of rewidling
De-extinction of the mammoth - aim to regenerate the mammoth steppe
What is reintroduction
Releasing/establishing an organism back into its known historical range
Planning for reintroduction involves
- Habitat suitability
- Threatening processes
- Size of potential populations – viable? Sex ratio?
- Long-term protection of habitat
- Anyone else in the niche?
- Distance from source population
- Post-release monitoring
Success criteria of reintroduction
- Produces a viable self-sustaining population in the wild over a given time frame
- An unsupported wild population of at least ‘x’ individuals
- Persistence of population for ‘x’ years
Importance of monitoring
- How do we know the effort was worth it?
- What can we learn from what worked and what failed?
- How do we know how much more effort is needed
BACI
Before, After, Control, Intervention
Why is science communication important
- Address urgent issues
- Make science more transparent
- Education
- Trust in science
- Inspire change
AWC’s mission
The effective conservation of all Australian animal species and the habitats in which they live
Who is the largest private conservation land owner in Australiua
AWC
How many properties does the AWC have
31 (over 12 million ha)
Example of AWC sanctuary
Shark Bay World Heritage Site
What mammal species have been reintroduced into Mt Gibson
- Numbat
- Bilby
- Shark bay mouse
- Western quoll
- Brush tail bettongs
Management outside the fence of AWC’s Mt Gibson sanctuary
- Cats and foxes present
- Increasing activity due to good conditions
- Two intentionally reintroduced mammals; several other reintroduced species detected
- Large scale Eradicat baiting program
- Camera array to identify cat activity hotspots
- Targeted trapping and shooting in hotspots
- Three Felixer grooming traps
Why is taxonomy important
- Taxonomy provides a critical framework
- Underpins conservation, ecology, biosecurity, agriculture, health and many other fields
- Australia is one of the most megadiverse countries (17)
- 70% of our biodiversity remains undescribed
Why don’t we protect marine invertebrates
- Not big, cute or furry
- Less food or fear connections
- Less history of companionship
- Commercial value exceptions
- Animal ethics – interesting insight
- Biggest contemporary threats - Over-exploitation and agriculture
Why are marine extinctions overlooked
- Species may become extinct before they are discovered
- Lack of knowledge
- Public disinterest
- Lack of resources
- Practical problems - e.g. access to environments
Pros and cons of the flagship taxon approach
- Flagship taxa focus community attention and support
- Resources for one taxon often have flow on effects for others
- Caters for narrow-range taxa, which may not fall into a conservation area
- Can be used to judge the effectiveness of conservation measures
Threats to biodiversity
- Habitat loss (land use change, over-exploitation, fire)
- Climate change
- Invasive introduced species (weeds, herbivores, predators)
Vision and purpose of Bush heritage Australia
- Vision: healthy country, protected forever
- Purpose: to return the bush to good health
When did Bush Heritage begin
Started in 1991 when Dr. Bob Brown bought two blocks of forest in Tasmania that were destined for wood chipping
Bottom up control
Limited resources for breeding and population growth
Top down control
Increased mortality from predation, disease, etc.
Managing impacts of introduced species
- Manage the environment
- Reduce resources for pests to breed (bottom-up control)
- Reduce survival of pests by lethal control methods (top-down control)
Effects of global warming on wildlife
- Distribution shifts
- Changes in phenology
- Adjustment in physiology (thermal)
- Adjustment in behaviour - behavioural trade-offs
- Mass mortality events
- Population declines
Behavioural trade-offs in warming climate
- Nocturnal activity > increased predation risk
- Retreating in a burrow > missed mating opportunities (fiddler crabs)
- Perching in the shade > lower foraging efficiency
- Resting in the shade > reduced foraging time > fewer yearlings survive (African wild dogs)
- Altered social interactions > male zebra finches sing less at 43 than 30 degrees > reduced mate attraction and territory defence
What is animal cognition
Any mechanism by which an animal acquires, processes, stores and acts on information from the environment
Southern Pied Babbler - example of how heat affects cognition
- Took longer/needed more trials for individuals to learn the association between colour and food reward as temperature increased
- Impairment of performance at higher temperatures
- Reduced learning performance in adults that experienced high temperatures as nestlings
- Reduced reproductive success in adults that experiences high temperature as fledglings
- Long-term effects of high temperatures during development on cognition and reproduction
Conservation implications for global warming
- Thermal profile of artificial habitat structures
- Translocations and thermal tolerance - e.g. western swamp tortoise
- The role of cognition: pre-release or in-situ training; learning and memory in translocations
What is anthropogenic noise
- Noise generated by human activities
- Increasing urbanisation, transportation networks, resource extraction
Effect of anthropogenic noise on social interactions
- Territorial behaviour
- Mate preference/choice
Example of effect of anthropogenic noise - great tits
- Females prefer males that produce lower frequency songs
- When background noise was played – females preferred males with higher frequency song
- Acoustic masking
What is acoustic masking
A reduction in the ability to detect, discriminate, or recognise a specific sound due to interference caused by another sound
what does anthropogenic noise influence
- foraging behaviour
- vigilance behaviour
- communication: signal production and reception
Results of magpie study
- Magpies spent less time foraging when loud anthropogenic noise was present (>50dB)
- Magpies were less efficient foragers when anthropogenic noise was present
- Magpies spent more time being vigilant when anthropogenic noise was present
- Magpies vocalised less often when anthropogenic noise was present
Information gained from population monitoring on Penguin Island
- breeding parameters
- diet
- habitat use
- breeding season
- moulting
- daily movement
How do we know what penguins eat
- regurgitants
- DNA analysis of faeces
- Stable isotopes of feathers
Threats penguins face
- Reduction of food availability
- Interactions with watercraft – collisions, interruption of time on surface
- Entanglements
- Pollution (e.g. oil spills)
- Disturbance of nesting sites (e.g. trampling)
- Predators (e.g. foxes, cats, dogs)
- Chemicals (e.g. PCBs, Heavy Metals)
- Storms
- Climate change
Management of penguin threats
- Reduce temperatures in nest boxes
- Maintain arrival points – storm damage
- Boardwalks – reduce impacts on nesting sites
- No night time tours
- Island closures
- Reduce impacts with watercraft – lower speed and education
- Advocacy for policy changes to minimise climate change
Why is PVA useful
helps us to identify main threats to a population
What are the 3 steps to PVA
- Find population projection over time
- Iterations of the population projection are made (100-500)
- The proportion of projections which reached a certain threshold (e.g. MVP) are determined
What is considered a biodiversity hotspot
- at least 1500 vascular plants endemic to the region
- 30% reduction in habitat
