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Tasmanian Devil - Frequently Asked QuestionsDisease Affecting Tasmanian DevilsFurther Information 1. Q. How do they get their name? A. Tasmanian Devils seem to have earned their name from Europeans. It is easy to imagine the unearthly screams, coughs and growls coming from devils scavenging - perhaps behind a settler's hut. The settler comes to investigate with an old kerosene lamp and sees these black and white animals with red ears, pink mouths and big wide teeth. The settler would get a fright and fall over, the lamp goes out, and they are left very scared at their encounter with the devil. Aboriginal people had several names for them. One was "tardiba" which does not seem to have a translation equivalent to the European word "devil". Presumably, aboriginals had a more rational and normal relationship with the animal. A. Many predators have black and white patterns like devils (another example is the orca, or killer whale). This black and white flash pattern seems to be an adaptation to break up the profile of the animal. In some respects it is a form of camouflage as it's breaking the shape of the animal. 3. Q. Why are their heads so big? A. The heads are very large in adults, particularly old males, because as adult males compete with females they have to subdue females. As their diet is mainly carrion, bone-crunching and breaking through thick skin is something older animals need to be able to do. Whereas younger animals have a relatively smaller head, they're much more supple and agile animals and seem to be much better hunters. In very old males, the head and neck can contribute nearly a quarter of the weight of the animal! 4. Q. Why are their whiskers so long? A. Not only are their whiskers long but there are lots of them. They are positioned in clumps far back on the top of the head plus in the normal 'whiskery' places. These long whiskers help foraging in the dark. They also help devils space themselves from each other when they are feeding on carrion. It helps them park around carrion without crowding - if devils whiskers are not touching each other when they are feeding they are safely outside biting range. 5. Q. How strong are their jaws? A. In absolute terms, there is no good measurement because you never know how hard they are biting. That applies to most animals but we do know the relative strength. Devils have jaws of biting power as strong as a dog about 4 times their weight. So a 10 kg devil has as powerful a bite as a 40 kg dog. In this respect they are very similar to hyenas, particularly the spotted hyena. 6. Q. How long do they live? A. Very few wild devils live longer than 5 years. In captivity, they may live a few more years. 7. Q. Are females and males the same size? A. No. Males are usually about one quarter as large again as the female. A typical adult female would weight 7 or 8 kg, a typical adult male would weigh 10 or 11 kg. 8. Q. Why are some individuals so dominant when feeding? A. Basically, the most motivated animals are the most dominant. That usually means the most hungry animals are dominant. Typically, females which have young ones to care for, (especially if they are in a den and therefore not in danger with the female) need lots of food and are very aggressive at social feeding encounters. They typically are very dominant. If all individuals were of the same hunger level the largest one would likely be the most dominant. 9. Q. Do they come out in the day? A. Where they are not harassed by people or dogs, devils love to very quietly and discreetly sun bake. All ages do this, the larger ones not necessarily being involved with the smaller ones. Lizards and devil pups have been seen out sunning themselves. The only animals that seem to feed in the daytime are very desperate or sick. 10. Q. Why are they not scared of artificial lights? A. They actually are a little scared of artificial lights at first, but eventually realise that the light is not going to harm them, With other devils about they are more concerned with competition. 11. Q. What is their hearing like? A. Their hearing is excellent. It seems to be the dominant sense. 12. Q. What is their sight like? A. Like most nocturnal animals their sight seems to be oriented heavily on black and white vision, and black and white vision is mainly designed to detect movement. So if something moves they have good eyesight whereas if something stays still they are unlikely to see it clearly. 13. Q. What is their sense of smell like? A. They seem to have an excellent sense of smell, although it is probably not as good as a scent hound. 14. Q. Why do they make so much noise? A. The noise is basically bluff to try and intimidate other animals so that there is no fight. Powerful animals like this often have sophisticated mechanisms to avoid fighting so they do not damage themselves. The sound helps sort pecking order. 15. Q. Why are their ears red? A. Their ears are red when they are stressed or very excited because the ears flush with blood. The ears do not have hair on them so simply large ears with very thin skin and lots of blood means they would be red. 16. Q. Why do they yawn? A. The yawning is in part a displacement behaviour which is a redirection of nervous energy to something that's harmless. An example is a person scratching their head when a policeman is talking to them. A yawn also serves to demonstrate that they are an animal with large teeth and a big mouth, but mainly it is a displacement activity, a sign of low level stress. 17. Q. Why do they hold their tails up? A. When they are very excited they hold their tail up no doubt as part of the body language to demonstrate to other devils that they mean business. When they are very angry they will hold their tail almost straight up. The tail can be held in many positions and the subtleties probably have much meaning in communicating the animals level of arousal or aggression to other devils. 18. Q. Why do they have fat tails? A. Most marsupials store fat in their tails and a fat tail is usually a sign that an animal is in excellent condition. 19. Q. Why are some injured in the face? A. Most devils with injuries on the face are adult males. Many of these injuries have been gained at the end of a mating period when the female fights off the male. Some of these injuries are obtained when males are fighting males for access to females. Very few injuries are caused at squabbles over food. 20. Q. Why do some devils have scars on the rump or neck? A. The scars on the rump are mainly caused when animals back into other animals to try and push them away from food. Basically it is safer to be bitten on the very heavily armoured, thick skinned rump than on the face. Scars on the neck usually indicate the animal is a female. The scars are from hair loss caused by males holding the female to subdue them. 21. Q. Do they have predators? A. In the past no doubt thylacines were predators of devils. Small devils come out in the day; they run risks from large birds of prey such as eagles, and very small devils run risks at night from large owls like the masked owl and large quolls like the spotted tail quoll. Almost certainly large devils will eat small devils if they are hungry enough. One reason that young devils can climb so well is possibly so they can escape large devils. 22. Q. What controls their numbers? A. In the past, competition and perhaps predation from thylacines would partly control devil numbers. Now, the controls are more likely to be food availability, and competition with other devils and quolls. Very high mortality from diseases (such as parasites) help control numbers. 23. Q. Does artificial feeding do them harm? A. As long as natural food is provided (such as dead wallabies that have not been poisoned but have died from road kill), artificial feeding does them no harm. In fact, by moving wallabies from roads to paddocks it probably saves many devils from being killed. Surveys of dead devils in one area of road showed that almost no devils were killed once dead wallabies had been removed from the road, compared to up to 10 road-killed devils per year when wallabies were left on this section of road. As long as feeding is not too regular and too much so that animals cannot become addicted to artificial food sources, feeding probably does no harm at all. 24. Q. Do they have diseases and parasites? A. Yes they do. Devils carry a number of internal and external parasites. They often have small numbers of ticks, tapeworms, and other parasites. Of great concern now is the Devil Facial Tumour Disease. 25. Q. What are they related to? A. Devils are most closely related to quolls. Their next closest relationship is with smaller marsupials and a more distant relationship is with thylacines. They are of course more closely related to all other marsupials than placental animals such as dogs. 26. Q. What does their Latin scientific name mean? A. Their Latin name is Sarcophilus harisii. That means Harris' meat lover. Harris is the name of the man who described them in scientific terms. 27. Q. Why do they fight so much? A. Fighting, often superficial fighting without serious contact, is common because it is the basic mechanism for setting pecking order. 28. Q. Do they injure each other? A. Very occasionally, mostly when they are fighting over mates, fighting during mating, and females injuring males. Rarely do they injure each other when fighting over food. 29. Q. Why do some feed peacefully? A. Devils vary enormously in personality. Some individuals are very calm and tolerant, others very excitable. It is possible that some animals seen feeding peacefully together are close relatives and therefore are more tolerant of each other. It is also possible that they are not so hungry and not very motivated to fight over food. 30. Q. Why do they eat so much? A. Many predators eat large amounts, the main reason being that they may not get to eat again for some time. Basically is safer to have your food inside you rather than carry it around where it may be stolen! 31. Q. How much can they eat? A. If they are not interrupted, devils can eat up to 40% of their body weight in 30 minutes. But as they need to consume about 15% of their body weight per day in the wild, even a huge feast like that would only keep them going for 2 or 3 days. 32. Q. What do they normally eat? A. Devils seem to eat any meat that is available. This includes birds, fish, even invertebrates such as moths and tadpoles, frogs and reptiles, and other mammals such as wallabies, echindas, platypus, wombats; in fact almost anything that they might find. They do have preferences. Devils seem to very much like wombat. This is probably related to the rich fat content of the food. This is because not as much has to be eaten for the same calorie count. What is normally eaten generally reflects what is available. What is available does not always reflect abundance because some very common food might be very hard to get whereas some rare food might be very easy to get. In wilderness areas where there is not much carrion, devils hunt a lot. Small ones hunt moths, tadpoles, frogs, ground birds, anything they can catch. The larger ones hunt correspondingly larger prey - wallaby joeys, wallabies, even wombats. There are records of adult devils catching adult wombats. Any incapacitated animal trapped injured sick is likely to be killed even if several times the size of devils. Most predators work like that. Animals are killed mainly to keep them safe or still while being eaten. 33. Q. Do they eat stock such as lambs and sheep? A. In some areas, particularly farm land, much already dead stock is eaten. Generally dead cows can only have small bits eaten - the udder, the mouth, the anus - because the skin is too thick for devils. Whole sheep can be eaten except for the large bones. Any small stock like sheep or lambs that are injured or incapacitated may be killed and eaten. New born lambs are sometimes at risk. If sheep have twins or triplets, weak members of the litters may be especially vulnerable. Poultry that roosts on the ground is also vulnerable. Most healthy stock is perfectly safe. 34. Q. Are devils dangerous to people? A. No, devils are not dangerous. They do not attack people although they will defend themselves if attacked or trapped. Devils, for all their appearance, are very timid, quiet animals that would much rather escape other animals than fight. However, devils are very powerful, and any bite could cause serious injury. Devils are wild animals and therefore should not be trusted with small children, just as you would not trust a large wombat or a large kangaroo with a small child. 35. Q. Do they form packs? A. As far as we know, devils do not form packs (a pack being an organised group of animals of the same species). However, devils can be found in one place in large numbers and they may even be trying to hunt the same animal. It does not mean they are organised even though the confusion they cause may give them advantages. 36. Q. How many young do they have? A. Devils have four nipples, so the females can only rear a maximum of four young. Usually there are three or four young - more, indeed, in the first year of breeding, less in the second and third year of breeding. Very few devils breed for four years. However, like quolls, devils give birth to up to twenty or thirty young at a time despite only having four nipples! Obviously, only a maximum of four of these can attach to a teat. This is an example of "selection of the fittest" right from the start. 37. Q. Where do they breed? A. Devils are of course restricted to mainland Tasmania. They breed over their whole range in mainland Tasmania. They breed in dry caves, hollow logs, burrows (particularly wombat burrows). They prefer dry and warm sites. They do not breed in exposed areas because the young are small enough that they are vulnerable to other predators and other devils. 38. Q. When do they breed? A. Most devils mate in March, and give birth in April. Young stay in the pouch until July. The young are then denned and come out of the den gradually over October-November-December. The season is spread out over several months, not every animal giving birth at the same time. That is, they are not all synchronised. In some places where there is much food and not so many devils, the breeding season is even more extended. The peaks in breeding coincide with the pups becoming independent just before Christmas when wallaby joeys often start to leave the pouch. 39. Q. How long do they stay in the pouch? A. About four to four and a half months. 40. Q. Are they territorial? A. Strictly speaking, they are not territorial. A territory is a defended core of home range. However, devils have fixed home ranges and a small mobile territory they carry with them. That is, they defend a small area of personal space. Females have small territories around den sites. There is much we do not understand about how devils arrange themselves in the landscape. 41. Q. How far do they travel? A. Radio tracking has shown that many devils will travel 10 - 20 km in a night within their home range. They do not repeat the same movements every night. If they find food early then they may not travel very far at all. We are not yet sure how far immature animals disperse from their parents. 42. Q. Were devils always in Tasmania and why are they here? A. It seems devils evolved in what is now Australia and remains of other species of devils including some very large ones have been found in fossil deposits. Very large devils evolved amongst our mega-fauna. Certainly devils have been in Tasmania for many tens of thousands of years. 43. Q. Were they in any other place than Tasmania? A. It seems devils were spread all over Australia and they may have been in Papua New Guinea. They probably became extinct on mainland Australia at least several thousand years ago, either through failure to compete successfully with dingos or through disease, climate change or another process. The actual cause of extinction is not known precisely. 44. Q. How come devils are active in the day in zoos? A. They have learnt in zoos that people or anything else will not harm them in the day and that is when they are also fed so people can see them. 45. Q. Why are some individuals wary, others confident? A. Like people or any other animal, devils vary immensely in personality traits. They also vary in experience. Animals that have not been frightened or harmed will appear very confident. Animals that have been frightened or hurt will be wary. Like many multiple litters, devils can have different fathers for the same litter, therefore personality traits can vary because of different fathers. 46. Q. How many live in Tasmania? A. Densities of devils vary greatly in different parts of Tasmania. In the high density areas, there seem to be about 20 devils living in about 10-20 square km. Of course, this number goes up when young come out of dens but it goes gradually down as young ones perhaps die or disperse. There are probably about 100-150 thousand devils in the wild. 47. Q. Do devils teeth keep growing? A. Yes, but very slowly. They also keep wearing, of course; often faster than they grow. Hence old animals can have worn down stumps for teeth. 48. Q. How many sets of teeth do devils have? A. Devils develop teeth at about 4 months at the first sign of eating food other than milk. They keep those teeth all their life. 49. Q. How do devils know which way scent leads? A. The same way that all other animals know. They test the air for increased intensity of smells ‚ the nearer the source the more intense the smell. They may move around to get a better scent, perhaps by moving downwind. 50. Q. Are devils endangered? A. No, but in the 1930s-40s they were extremely rare and some people thought they may become extinct. Even though devils are common now, on an island (Tasmania) population levels could change quite quickly with disease (see below) or other problems. Devils suffer all manner of pressures from people (direct persecution, roadkills, loss of den sites to development, etc) but have adapted well to free range stock management (provides lots of carcasses) and the increase of wallabies and possums from widespread, improved pasture. 51. What is Devil Facial Tumour Disease? A. Devil Facial Tumour Disease is a term used to describe a fatal condition in Tasmanian devils which is characterised by the appearance of obvious facial cancers. The tumours or cancers are first noticed in and around the mouth as small lesions or lumps. These develop into large tumours around the face and neck and sometimes even in other parts of the body. Adults appear to be most affected by the disease - males the first affected, then females. Badly affected devils have many cancers throughout the body. As the cancers develop in affected devils, they find it hard to ingest food. The animal weakens further making it difficult to compete with other animals for food. Affected animals appear to die within three to five months of the lesions first appearing, from starvation and the breakdown of body functions. 52. Q. How fast can devils run? A. On rough terrain devils can run faster than a person; on very smooth terrain they cannot run as fast as a good human runner. Devils have been 'clocked' running on a flat road at nearly 25 km/h for up to 1 km. Devils can run at 10 km/h for many kilometres. 53. Q. Can devils climb? A. Young devils climb very well, larger devils not so well, but they are very persistent. They have good gripping ability with their front paws even though they do not have retractable claws (as do cats). They use their large footpads on the hind legs as contact grips and friction pads. 54. Q. Can devils swim? A. Devils can swim very well. However if they have young in the pouch they avoid swimming for more than very short distances. Devils actually love water and will wade and splash about, even sitting or laying down in it to cool. They will often dabble in water with their front paws, somewhat in the manner of racoons. Captive devils (and probably wild ones) will sometimes cache (store) food in water bowls. 55. Q. What use are devils? A. Devils have a number of values from intrinsic and psychological, through financial to ecological, even a value to Tasmania's famous "clean green" image. Devils are the very essence of wildness, they are omni-present, always there but never there. They play an important role in the Tasmanian psyche, and possibly more than anything else, they are an icon of wild Tasmania. Devils have inspired story tellers and writers. Devils also offer a great example of wildlife succeeding amongst all manner of pressures, a true 'battler'. Devils are of increasing importance to tourism. Devils are of long time importance in marketing. We have sports teams, products, many items marketed as devil products or associated with devils. Thanks to Warner Brothers there has been some worldwide marketing of devils, albeit a somewhat fanciful image. Devils are basic to displays of Tasmanian wildlife in zoos and wildlife parks. Devils also have a fundamental role in our ecology. They are nature's auditors. Sick animals, slow animals, diseased animals, dead animals are all eaten by devils. Devils are probably a controlling factor for feral cats and a very important line of defence against additional introduced animals, particularly the Red Fox, an animal which is devastating to mainland Australia and a potentially catastrophic introduction to Tasmania. With high densities of devils, it could be very difficult for a vixen to rear young since they have to leave young fox cubs for long periods. A fox den is smelly and messy and would be very obvious to a devil. 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Tasmania Online | Service Tasmania This page - http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/BHAN-5372WP?open - was last published on 5 September 2005 by the Department of Primary Industries, Water & Environment. Questions concerning its content can be sent to NatureConservation Enquiries by using the feedback form, by mail to GPO Box 44, Hobart, Tasmania, Australia 7001, or by telephone to 03 6233 6556. Please read our disclaimer and copyright statements governing the information we provide on this site. A text version of this page is also available. | ||