When you were little (or any age really no judgement here) did you ever have a red cape or blanket and run around pretending to be little Red Riding Hood? When I was younger my mother made me a cape so I could pretend to be a bat. No not a cape so I could pretend to batman, a cape so I could pretend to be a bat. It had pointy ears in the hood…. I still have that cape somewhere and I definitely have never in my adult life put it on and run around pretending to be a bat….
Before I prattle on about how amazing bats are I think it’s best I address the major arguments against bats. Normally in discussions with people about bats the following seven issues nearly always come up:
1. they wreck/steal the crop
2. they poo everywhere and you can’t remove it
4. Hendra virus
5. noisy and smelly
6. so much poo it needs to be mentioned twice
7. they’re ugly and scary
The first issue is definitely a very serious matter. Without farmers doing the amazing work they do the majority of humans would starve to death. I was raised on a hobby farm of sorts with a small orchard and vegie patch and it was always extremely frustrating when the rats, possums and parrots ate our crops. Especially if the possums took one bite out of every orange…. Now, our ‘farming’ was to supplement our diet and we by no means relied upon it especially not as a source of income. I can barely imagine the devastation that farmers face when their crop is decimated by wildlife. However, like always, the natural world is not a simple system and the solution to this problem is not to kill the bats. Let me explain.
Bats are amazing pollinators. This means that they transfer pollen from a male plant or male part of the plant to a female plant or female part of plant. Essentially, bats help plants reproduce. This relationship is referred to as, ‘chiropterophily’.Yes bees and birds are also pollinators but many flowers open exclusively at night and therefore rely on bats as their pollinators. When it comes down to it, without bats there would be no tequila. So while the bats may be wrecking crops with their droppings and eating fruit, they are simultaneously pollinating. A very complex question, one I do not have the complete answer to is, “without bats pollinating crops, would our crops be so successful?”. My guess would be no but it’s just that, a guess, albeit an educated one. If this were the case then there needs to be a cost benefit analysis, are the bats pollinating and helping produce more crops than they are destroying? If the bats are having too great an impact on the crop then white, coarse netting over trees is an effective measure against bats. Black or fine mesh netting will most likely result in the bats becoming entangled.
Bat poo is known for being very: smelly, messy, sticky, corrosive and difficult to remove. The bright yellow and orange smears that you may have seen on your car are probably an unwanted gift from a flying fox. The poo of insectivorous bats is very similar in appearance to that of mice. Bat poo, just as it is the case for any animal excrement, is also known to carry disease and therefore care must be taken when removing it. The best action is prevention. Keep your car under cover from dusk to dawn and do not park under trees that are likely to attract flying foxes during this period. Not everything of course can be covered or taken indoors between these hours so instead we need to look further afield in our prevention. Due to habitat destruction bats are forced to adapt to the environment that is available to them. This environment is often parkland, agricultural land, riparian zones (land surrounding river and creeks) and trees lining the roads of suburbia. They also have been known to take to sheltering in buildings. If their original habitat had not been destroyed then the bats would have no reason to enter the somewhat hostile and foreign human environment. If you want to prevent bat droppings on the side of your house or across the bonnet of your car, planting trees and campaigning for the protection of the natural environment is a great place to start.
Bats are incredibly diverse group of organisms. While some species of bats are pollinating crops, and yes eating the fruit, others are eating insects. They are the only major predator of night active invertebrates. Favourite foods of bats are: lacewings, cockroaches, gnats, and mosquitoes. Some farms have even begun to erect bat boxes on the edges of their crops to encourage insectivorous bats to feed upon crop destroying insects. The bats have shelter and food and the farmers may not need to resort to using pesticides.
By eating insects bats are also helping stop the spread of diseases such as malaria and ross river virus. However, they are carriers of other diseases. The most talked about of these being rabies. My expertise is on Australian wildlife so if you’re an international reader the following facts may not apply to you. Rabies is not currently recognised as being present in Australia therefore it is unlikely you’re going to catch it off a bat. However, we do have ABLV, Australian Bat Lyssavirus. During one particularly hilarious microbiology lecture, the course co-ordinator and the guest lecturer argued over whether rabies should be recognised in Australia. This is symptomatic of the somewhat contentious ruling of Australia being rabies free. For now let’s ignore that debate and just talk about what ABLV is and why you don’t really need to worry about it.
Australian Bat lyssavirus is a virus transmitted from bites and scratches as well as saliva. It has similar symptoms to rabies, is treated the same way as rabies and just like rabies is fatal if left untreated. If you want to know more about rabies and ABLV follow this link: http://www.health.nsw.gov.au/infectious/factsheets/pages/rabies-australian-bat-lyssavirus-infection.aspx
Sounds scary and it is a scary disease but the likelihood of ever catching lyssavirus is so low I am more worried about the cows rising up against us in mass mutiny. If you don’t want to catch ABLV do not touch bats. If you do want to touch bats then make sure you’re vaccinated and follow the correct safety protocol. Catching ABLV is very unlikely if you are not in direct contact with a bat. By very unlikely I mean if you catch it you might also be about to win the lotto ten times over because the probability of catching ABLV without direct contact with bats is just that low. By direct contact I mean scratches and bites not just being in the same room as a bat. It is estimated that less than 1% of the wild bat population has ABLV, so even if for some reason you are scratched by a bat it is unlikely to have the virus. The only recorded cases of ABLV in Australia have been from people that had direct contact with bats. If you don’t want to get infected with ABLV do the following:
- if you see a bat don’t touch it
- if you see a bat on the ground do not touch it
- if you think licking a bat is a good idea it is not
- if you think a bat is injured and want to help it, good on you for doing the right thing but do not touch the bat and instead contact a specialised wildlife carer
- if you want to play with bats go get vaccinated and make sure you know how to handle the bats properly for both their sake and yours
- if you get scratched or bitten by a bat or for some reason got their saliva in your eye (why were you touching it in the first place?) then wash the area and seek medical attention immediately. They will probably give you a series of post-vaccinations
- do not touch the bat
Now that we do not need to worry about rabies and ABLV anymore let’s move onto hendra virus. I was raised in the outskirts of a country town whose inhabitants love their horses. Bats are therefore unwelcome guests in the district because of the fact they are known to carry hendra virus which can be deadly to horses. Hendra virus is carried by flying foxes and is most commonly associated with the black flying fox. It is transferrable from bat to horse and infected horses can then pass the virus onto humans. Bats can not pass the virus onto humans directly. I will restate that, bats can not pass the virus onto humans. The virus must first pass from bat to horse and only then can humans catch it. Insectivorous bats are not known to carry hendra virus, only fruit bats. Horses that become infected with hendra have a 75% mortality rate and in humans it is 50%. Hendra virus prevalence is extremely low and its spread is preventable. In order to lower the probability of yourself, pets or horses from contracting hendra you can take the following precautions:
- do not place feed or water beneath trees
- cover feed and water containers
- flying foxes are attracted to everything sweet so do not leave fruits and molasses where they can access it
- observe which trees attract flying foxes and fence them off to stop horses sheltering beneath them
- move horses to a paddock not containing flowering trees when the flying foxes are
- present (certain periods of the year and dusk to dawn)
- consider stabling horses from dusk to dawn
- remove debris beneath fruit trees
- remove trees from your garden that are known to encourage fruit bats or alternatively remove the fruit from these trees
- for more suggestions read: Queensland Horse Industry Council Guidelines: Property Design (PDF 434.44KB) and Bats and Trees (PDF 112.64KB).
The bats that tend to be noticed by humans are the flying foxes and they are fairly social creatures. Like any social animal they communicate with one another. Flying fox communication is based on two mediums, one is scent and the other is sound. The intense smell associated with flying foxes is not because they are dirty but is the result of secretions from scent glands on their shoulders. Flying foxes regularly groom themselves which aids in spreading the scent across their bodies. Males use these scent glands to mark their territories. Mothers identify their young by their scent and their calls. They also call repeatedly to eachother especially as they wake at dusk and come into roost at dawn. Their twitterings are the equivalent of, “honey I’m home!” and “mum i’m hungry!”Little can be done to reduce the smell and noise caused by flying foxes. However, noise and smell can dramatically increase due to stresses. This is considered normal for any animal species. For example, if you ever have the chance to handle a tawny frogmouth you will be taught the ten second rule. Once you get a hold on a tawny frogmouth they will ALWAYS defecate because they’re carnivorous birds it is runny and extremely smelly. So, if you pick up a tawny frogmouth wait 10 seconds before moving it anywhere or make sure you have a change of clothes. Bats, if disturbed, will begin to call to eachother. Translated into english these calls may be along the lines of, “mummy there’s a monster under the tree!”, “HAROLD!” or, “umm… I think there’s a burgular dear… do you want to go see…?”. Therefore, if bats are left alone, they will make less noise.
If bats are stressed then there can be multiple negative consequences. When animals are placed under stress their immune systems are impacted upon. This is evident at exam time when all students inevitably come down with a cold even though its summer. A stressed bat is therefore more likely to contract disease than an unstressed individual. Stressed animals also shed bacteria and may present with diarrhoea. When under high levels of stress the females may even abort their foetuses and discard their offspring. This is a defence mechanism built by evolution. Elephants for example are more likely to stand and protect their young because they have a high energy budget in the production of their offspring. Whereas, evolution has determined for other species it is better for the species as a whole to just reproduce again next season and leave this season’s young behind. It is a very sad fact of life but it can not be changed.
Bats are seen in a very negative light due to multiple factors. There are definitely disadvantages to the presence of bats however the advantages are greater than the inconveniences. Their potential impacts have been taken grossly out of proportion resulting in an unfounded hostile attitude towards them. Entire townships have been known to band together to force the removal of a local bat colony. If the bats were successfully removed from one town, they would relocate to a new roost. Due to the lack of natural habitat the new roost may need to be another town. Removing bat colonies are not dealing with the problem but simply moving it along. The process of moving the bats is stressful and as previously stated, stressed bats shed bacteria, may abort foetuses and defecate profusely. So now we have a situation where the bats are disturbed, flying around with diarrhoea, foetuses are being aborted, babies dropped and body fluids from the bats are being excreted. Attempting to relocate the bats rather ironically results in the perfect environment for the spread of disease (stress, body fluids and bacteria).
One of my university lecturers would often say, “without bats the rainforests would die”. He was unfortunately correct in his statement. Bats are pollinators and dispersers of seed. Without them many of the rainforest plants would be unable to reproduce. The rainforest is a tightly coordinated ecosystem and if even a few species could no longer reproduce, then many others would suffer due disturbance to the ecological equilibrium. The likely consequence of this disturbance would be the demise of the entire system or such a radical change it was no longer comparable to the original environment.
I could talk for hours on how amazing bats are but I shouldn’t need to. Bats are living organisms and deserve the right to continue to live. They are an incredible group of animals but does that mean they have a greater right to live than a comparatively boring animal? As an ardent animal lover I am unaware of such an animal but the point still stands. Bats are critical in maintaining the natural world and their presence means we are able to sit beneath a waterfall in a rainforest as we drink tequila.
As for bats being scary and ugly just look at the little faces below: