Q 31-39 Flashcards
Describe the transmission of the Devil facial tumour disease and its effects on individuals and the population more broadly.
- affects at least 65% of the tassie devil population and has decreased the population by at least 50% = endangered species
What is it?
- aggressive parasitic cancer that is transmissible between tassie devils only
- transmitted through biting behaviours = very common in devils, hence why spreads so much. biting behaviours can be sexual behaviours, or fighting
- the cancer cells originally cause no immune reaction, later become small bumps in the mouth, then progress to large tumours in or around the mouth/face/neck area
- eventually become so painful the tassie devil cant exhibit natural behaviours, to the point of not eating = starvation = death
- fatal most of the time = affects population so much
new clones:
- has been an emergence of a new clone DFTD2, hasn’t spread anywhere near as rapidly as the original DFTD and is different genetically
What is being done to help population numbers?
- no treatments at the moment, but so much research going into how to stop this aggressive cancer
- reintroductions of non infected Tassie devils, however concerns this isn’t helping as again the rate of the population declining is so concerning
- lots of work being done with captivity programs and breeding programs
- hoping a vaccine can be made in the future
Name a disease that has had major impact on a wildlife population and describe the drivers of this disease emergence or re-emergence as well as its impacts?
The Devil Facial Tumour has had a major impact on the Tassie Devil population and they’re now considered endangered species.
- affects at least 65% of the tassie devil population and has decreased the population by at least 50% = endangered species
Emergence:
emergence of the disease was in 1996, where it’s reported a schwann cell would have mutated and become cancerous, from there the nervous system created this cancerous disease that can be passed on between the species.
What is it?
- aggressive parasitic cancer that is transmissible between tassie devils only
- transmitted through biting behaviours = very common in devils, hence why spreads so much. biting behaviours can be sexual behaviours, or fighting
- the cancer cells originally cause no immune reaction, later become small bumps in the mouth, then progress to large tumours in or around the mouth/face/neck area
- eventually become so painful the tassie devil cant exhibit natural behaviours, to the point of not eating = starvation = death
- fatal most of the time = affects population so much
new clones:
- has been an emergence of a new clone DFTD2, hasn’t spread anywhere near as rapidly as the original DFTD and is different genetically
What is being done to help population numbers?
- no treatments at the moment, but so much research going into how to stop this aggressive cancer
- reintroductions of non infected Tassie devils, however concerns this isn’t helping as again the rate of the population declining is so concerning
- lots of work being done with captivity programs and breeding programs
- hoping a vaccine can be made in the future
What are the environmental drivers of zoonoses? Illustrate your answer with examples.
What is a zoonotic disease?
- a disease that can be transmitted from animals to humans
- e.g’s = Q fever, Hendra virus, Salmonella and Lyssavirus
Deforestation
- Removal of an animals habitat causes them to migrate = causes them to live in closer proximity to humans = more chance of disease to spread
- altering an ecosystem, causing imbalance which can have major effects including evolving diseases
- deforestation actually worsens or can accelerate the effects of climate change which has a major effect on animals and disease
Climate change
- extreme weather events, such as humidity, storms, floods, etc can actually help diseases strive in those certain climates
- climate change = warmer climates = means best climates for mosquitos to thrive in meaning more spread of those mosquito borne diseases to effect us
- another example is in Africa: heavy rainfall in warm conditions is causing fruit to grow more rapidly, which is attracting bats causing the risk of zoonotic disease such as ebola to spread more
Wildlife trade
- involves the movement of dead or alive animals globally or locally
- has been linked to the emergence of countless diseases when not closely regulated
- this is due to the contact between humans and animals being increased, as humans are more susceptible to injuries such as biting/scratching
- also very stressful for animals if alive, therefore emergence of disease happens
Intensive farming
- as we know intensive farming is a large amount of stressed animals in a small area, which is the perfect environment for diseases to spread, including zoonotic ones between workers who are in close contact with these animals
- swine flu is an example of this happening
- therefore people argue that less intense farming conditions are safer for not only animals as its less stressful, they can build their own natural immunity, promote better health and therefore have less cases of disease
Increased human population
- the growing human population is causing disruptions to ecosystems, as i explained earlier can therefore lead to increases of disease arising
- increased travel to tropical destinations comes with risk of infectious diseases
Human-Animal Bond
- with the human population increasing, and more housholds owning pets = more of a chance of diseases to spread
- this can actually lead to increased trade of exotic pets around as well such as reptiles, birds, fish, etc
Illustrate the principle and use of the “mark-recapture” technique
“Apart of wildlife management is managing, understanding, monitoring and researching populations of species. A variety of methods exist in order to help us do so, but some don’t work depending on the species, or surrounding habitat, or due to insufficient equipment or staff.”
“The mark-recapture technique has been found to be very useful and successful in wildlife management research as it can practically be used on any species from insects to large mammals.”
What is it/how is it done:
- catch one or group of animals through trapping/fencing
- mark them using paint or tags, then release back where they were found
- later down the track (wks or mnths) set up traps/fencing again to capture some species
- some will hopefully be tagged and some wont = how the population number is calculated
Example of how its calculated:
- First Sample X Second Sample = __
- Then divide the amount of second samples that were marked
So let’s say 10 quolls were captured and marked, then at a later date 20 were captured, but only 5 of those 20 were marked. That means, 10 multiplied by 20 divided by 5, equals a population of around 40.
Benefits:
- allows us to get an accurate population number when a manual count cannot be performed
- far less hamrful and stressful than other techniques
- can also monitor birth/death rates
Things to be aware of with this technique:
- ensure the tag wont fall off if the animal is growing (caught young) or if the type of species shed. also ensure you’re not limiting their movements
- be strategic on where you set up traps - what attracts them, whats their track like, where will they most likely be
- understand how much ground these species cover to ensure your calculations are correct
- ensure you have left enough time between captures so the animals had enough time to gel to make countings accurate
Explain why and how we mist net birds
- Great way to monitor species within a certain area
- can get an understanding of populations (how many present in that area) or look at the birds up close to take data (sex, species), tag them, etc
- When the mist nets are set up they’re essentially invisible for the birds, so they fly straight into them
- i recall on camp discussing a permit is required/or something is required in order to set up the netting, also need a purpose
How to set it up:
- start by hammering first pole into the ground
- get the netting untangled and place it over the first pole
- secure the first pole with a rope thats attached to something nearby
- once first pole is secure, set up second pole
- undo the netting and put it over the second pole
- attach rope to second poll
- open up netting, ensure no tangles now its open and ready
When its set up:
- ensure you’re always watching, can be a slow process but also fast
- start with untangling one leg, then focus on the body while being gentle
- may need to cut the netting worse case if bird is really stuck
- once bird is untangled you can start recording data, etc
Benefits:
- setting up/using the nets is relatively easy/fast compared to other capturing/trapping methods
- low observer bias - you get what you get
- ability to detect species that could be missed other ways
- allows us to examine the birds up close
Disadvantages:
- can be time consuming, esp if no catches which will happen
- untangling birds can become quite hard, stressful for animal if doesnt happen fast
Describe what capture technique you would use to catch a Mallee Dragon (Ctenophorus fordii). How you would set these traps and the things that need to be considered to ensure best practice.
“When considering capture techniques in wildlife management there’s a couple things you have to consider such as the type of species, their behaviour, where you can find them and more. The Mallee dragon for e.g is a small lizard found in dry, sandy areas of SA”
- The best capture technique = pitfall trap = Calperum
- determine the amount of pitfall trips you want to set up, location, etc
How to set up pitfall trap:
- Pick your location, ensure it is flat ground with a mixture of shady, covered areas as well as areas that receive direct sunlight
-Dig a small hole, enough so the bucket can fit but isn’t sticking out or is too deep, then fill empty spaces with dirt
-Mark two straight lines (approx. 1 metre each) on both sides of the bucket, and place netting across the bucket
*The purpose of the netting is so when the lizard is running along and bumps into the net, they will hopefully turn and run into the bucket
-Then fill any holes/gaps from the netting with dirt again so they cant squeeze under
-Fill the bucket itself with some dirt, create some hidey holes, chuck some leaves in, make it as comfortable as possible for the animal.
-Ensure you leave a tag somewhere nearby the pitfall traps so you know where they are
Best practice:
- check traps at least twice a day (am/pm) = dont leave animal in there for too long (stressful, no food) esp in direct sunlight
- ensure hidey holes/shrubs/grass is in the bucket so it feels semi natural and have places to hide as they are vulnerable
- ensure enough sand/dirt is at the bottom of the bucket as they do literally fall into the trap, make sure they have a nice landing
- when packing up, leave the land how it was found. No holes left in the ground, even out the sand/dirt
- release animals in similar area of where they were found and don’t take too long to release
How would you examine a yellow footed rock wallaby and what are the critical aspects to minimise stress and risk to the animal and animal’ handler?
Intro
- safe handling a yellow footed rock wallaby ensures safety not only for the examiner and handler, but also the animal themselves.
Transfering animal from net to bag:
- ensure the bag isn’t see through, instead a nice thick material so the animal cant see (more calm)
- also not too thick as would be hard to determine where the animal is in the bag and may accidentally expose the head
- when wallaby is in the net, grab the base of its tail through the net, while moving the other hand into the net. then eventually hold base of the tail in the net
- transfer the wallaby into the bag with the feet of the wallaby facing the person who has hold of the tail = not putting bag holder in danger
Examining the wallaby:
- try to examine in the shade instead of direct sunlight = can overheat
- never expose the head, always identify where the head is in the bag
- taking weight = leave in bag & taking measurements, only bring out the appropriate limb to measure, never take out entire animal
- Blood sample: always take from the tail vein, therefore only need to tail out of the bag and the handler and safely secure the rest of the body by restraining (no biting/scratching/kicking). The handler also doesn’t have to hold off the vein for the blood taker, can use rope to hold up the vein (attention strictly on animal then)
- Pouch examination: turn animal onto its side gently, inbetween your legs (dont apply pressure), then pull one leg out of the bag and pull it back slightly, exposing the pouch (this is a form of restraint). OR handler can sit with the wallaby tail inbetween their legs, with the wallabies legs tucked into the bag, again exposing pouch.
- Ear tagging: again firm restraint but not too much pressure, ensure control of the head/legs
Release:
- have the bag facing away from you and ensure wallaby has a clear view of where it can go. Expose the head out of the bag and again point them in the direct you want them to go.
What unmanned aircraft can be used for in relation to wildlife management and/or conservation. Describe at least 2 examples along with this technique’s limitations.
Intro:
- Unmanned aircrafts = drones = research tool to help workers in wildlife management
- used for a variety of reasons and different ways = can be to monitor populations, behaviours, tracking movements
Bushfire e.g: example of finding populations/assistance
- Set up drones to seek for wildlife after natural disasters such as a bushfire
- allows us to find how many animals such as koalas are out there = population numbers that survived, inspecting for injuries
- Able to locate and collect if require medical assistance
Poachers e.g: monitoring example
- Poaching = illegal trafficking and killing of wildlife
- puts animals at risk of extinction, also extremely cruel
- drones being set up in parks to monitor if poachers are present = protecting the species
Research - Indiana bats e.g:
- Indiana bats = endangered
- therefore wanting to study them to understand them better = may be able to help increase populations
- Mix of monitoring with drones and GPS collars = trapped, collared, released
- collars means researchers could track where the bats live location was = send drones to that location
- Able to observe them exhibiting natural/normal behaviours such as where their habitat is, understanding their diet, behaviour better, climates they live best in, reproductive behaviours
- allows researchers to come up with solutions
Limitations
- Drones can make species feel threatened when noticed = altering natural behaviours = may not return to that place again
- can attempt to attack the system putting the animal at risk of injuries
- safety concerns in the case of a system failure
- should be noted too that countries vary when it comes to their laws regarding drones bc they can be seen as dangerous
- overall a bit expensive
What are camera traps? What are they used for?
How camera traps work
- camera trapping = a camera placed in a habitat that takes pictures of the animals present in that environment
settings include:
- take a picture automatically when movement is detected
- take a picture every 15 secs/20 secs/ etc
- camera can attract a certain species: can have settings where they have a call, these can be used for feral cats for example
What are they used for:
- help monitor/study species populations, interactions with the environment, population sizes, etc. Also helps understand behavioural or activity patterns of the animal. Very little human input, therefore species are acting natural and are undisturbed.
How to set one up:
- consider what location will get the best results
- available food/water sources
- tracks or droppings present
- burrows/hidey holes
- consider the species you’re wanting to capture: obvs if tall animal = place high in tree, or if short/small, then lower to ground
- ensure nothing is infront of the camera (branches e.g) = false images/readings
Advantages:
- wildlife friendly: doesn’t disturb the animal, may freeze for a moment due to flash but otherwise relatively safe/nonstressful for them.
- takes care of the environment: not changing the environment or habitats in anyway, arrive to set up, then taking down
- not labour intensive
- easy to use
- has been shown to have great results for studies
Disadvantages:
- Can spook the animal by the flash, rare but can happen
- can change behaviour therefore, may not return to that spot as seen as a threat
- can be costly
- doesnt work in particular climates sometimes, such as extreme heat or very humid climates
What are GPS /VHF radio collars being used for? What are the challenges and limitations associated with this technology?
Why use tracking collars?
- allows researchers to collect data regarding daily movements, such as migration data, helps understand behaviours better, understand data regarding dietary habits, also keep track of death rates/causes of death in populations
How are collars put on?
- Animal is typically trapped, fitted with a collar then released back into the wild
VHF collars
- ‘Very high frequency’ collars which sends radio signals to the individual tracking the animal
- The tracker can know the exact movements and location of the collared animal
Advantages -
- easy to use
- cheaper option compared to others
- can be fitted on a variety of animals
- has internal antennas if it were to be chewed on, but also can have external antennas too
Disadvantages -
- researcher has to be present on the field, therefore way more labour intensive than other options and can be super time consuming
GPS collars
- new and advanced technology where satellites are used to recieve very precise data on the animals movements and current locations
- All the same capabilities as VHF, except offer even more precise data
- Major advantage is that they can be used in areas that are harder to reach/more isolated for researchers
Overall disadvantages of all types of collar trackers
- limited with the animals you are able to study on, too heavy for some smaller animals, not large enough for larger animals
- collar can be uncomfortable for the animals, which will change their natural behaviours = not the most accurate data
- While researching this topic, I found a few articles regarding welfare concerns of animals wearing collars again just if theyre too heavy, also unable to groom in certain areas, etc
- Depending on the type of collar you select, may be fairly pricey but could come with a bad battery life = waste of money? better research options?
