What do Tasmanian devils look like?
The world’s largest surviving carnivorous marsupial, the Tasmanian devil has a thick-set, squat build, with a relatively large, broad head and fluffy thick tail. The fur is mostly or wholly black, but white markings often occur on the rump flanks and chest. Adult males are larger than adult females. Large males weigh up to 14kg and stand about 30 cm high at the shoulder. A typical adult female would weigh 7 or 8 kg. Devils reach adult body size by two years of age.
How did they get their name?
Imagine how European settlers first encountered the Tasmanian devil. Unearthly screams, coughs and growls come from the bush near a settler’s hut. The settler comes to investigate and sees dog-like black and white animals with red ears, wide jaws and big sharp teeth. The settler thinks they’ve glimpsed the hounds of hell or did they hear a brush tailed possum screeching and blame the devil? Both have an impressive screech!!
Aboriginal people had several names for devils. One of which is “poirinna”, this name comes from the “parrdarrama” language of the “pydarerme” band from “turrakana” (Tasman Peninsula).
Why are they black and white?
Few mammalian predators have black and white patterns like devils. The others include skunks and some whales (such as orcas and Dall’s Porpoise).
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, making it difficult for prey to distinguish the shape of the animal. The paradoxical question however is why then are 10 per cent of devils black with no white markings?
Devils “display” to each other a lot with their head held high and with a wide gaping “yawn”. When they do this the white blaze on the chest is obvious, could this enhance the display objective? Similarly, when devils interact aggressively, the loser turns and runs making the rump display prominent.
How long do they live?
Very few wild devils live longer than 6 years. In captivity, they may live to 7-8 years of age.
In early 2018 the Save the Tasmanian Devil Team were excited to trap Boots, a devil they released at Narawntapu in 2015. Before his release Boots had lived in captivity for 4.5 years and now a further 2.5 years in the wild which makes him the longest recorded surviving translocated devil in the wild, a true survivor.
Where do they live?
Despite the decline in numbers since the detection of DFTD in the 1990s, Tasmanian devils remain widespread across Tasmania from the intertidal zone to the sub-alpine areas. They live in coastal heath, open dry sclerophyll forest and mixed sclerophyll-rainforest. Devils will live almost anywhere they can find shelter by day and find food at night. They also take advantage of roads and tracks and the interface between native habitat and agricultural paddocks, where their favourite prey species are often found. They shelter in rock piles, log piles, hollow logs, abandoned wombat burrows, thick clumps of vegetation and sometimes under buildings.
Where and when do they breed?
Tasmanian devils breed in dry caves, hollow logs and burrows, particularly wombat burrows. They prefer dry and warm sites and avoid exposed areas because while their young are small, they are vulnerable to other predators.
Most Tasmanian devils mate between February and May and after a gestation period of around 21 days the young are born. As many as 40 young are born, but a maximum of four can be accommodated in the mother’s pouch, which has only 4 teats. Young stay in the pouch for about four and a half months. After this time the young start venturing out of the pouch and are then left in a lined den, often a hollow log. Natural maternal dens are lined with soft grass but those near human habitation are often lined with stolen items such as clothes, towels or plastic bags. Young are weaned at five to six months of age when they weight around 3kg and have usually left their mother to live independently by late December.
Females breed on average for three years and typically start breeding at the end of their second year. Generally, more young survive in the first year of breeding, less in the second and third years. Very few Tasmanian devils breed after four years of age.
Research has shown that the presence of DFTD in a devil population over several years results in a change of breeding behaviour. Females begin to breed earlier, at 1 year old, but as they need to be physiologically ready to mate, often they won’t come into oestrus until well after the usual mating period. This extends the breeding season from February to July. The result for the population is that there may be females with pouch young for most of the year, and juveniles dispersing from December through to June. This situation is also true of low-density disease-free devil populations.
How strong are their jaws?
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 the highest relative bite force of living mammals and equates to jaws with biting power as strong as a dog about four times their weight. Therefore, a 10 kg devil has a bite as powerful as a 40 kg dog, in this respect they are very similar to hyenas, particularly the spotted hyena. Relative to body size they have a bite stronger than a Bengal tiger.
Tasmanian devils have strong carnassial teeth made for crushing bone, premolars and incisors for tearing flesh and canines for killing. The adult teeth wear down with age and are not replaced.
What is their hearing and sight like?
Their hearing is excellent. It seems to be the co-dominant sense along with sense of smell.
Like most nocturnal animals they have black and white vision. Black and white vision is particularly good for detecting movement, however for stationary objects discrimination is less effective.
What is their sense of smell like?
Tasmanian devils have an excellent sense of smell and use it to track prey and find carcasses. Devils use common latrines (toilet sites) and scats deposited at these are used as a means of communication. In this way a devil will know which other individuals are in the local area, including their sex and breeding status.
Why are their heads so big?
The heads are very large in adults, particularly old males. Adult males compete for females and, once victorious, they need to be able to subdue the females in order to mate with them. They may drag a female to a den and hold her there sometimes for days during mating. The large head, mouth and teeth are an effective barrier to other males that might want to join the fray.
As their diet is mainly carrion, bone-crunching and breaking through thick skin is something devils need to be able to do. The skull has a strong sagittal crest (central ridge) with very strong jaw muscles attached, in turn the neck needs to be big and strong to carry this crunching machine. In very old males, the head and neck can contribute nearly a quarter of the weight of the animal.
Why are their whiskers so long?
Not only are their whiskers long but there are lots of them. They are positioned in clumps on top of the eyes, muzzle and in the normal ‘whiskery’ places. These long whiskers help when they are foraging in the dark. They also help devils space themselves from each other when they are feeding on carrion together – if devils’ whiskers are not touching each other when they are feeding they are safely outside biting range. When devils are agitated or alert they raise the whiskers. They are both sensory and behavioural devices, handy tools really.
Can Tasmanian devils climb?
All devils can climb to some degree. Young Tasmanian devils climb very well, but this decreases with age so that adult devils do not climb particularly well, but they are very persistent. They have good gripping ability with their front claws and paws even though they do not have retractable claws like cats. They use their large footpads on the hind legs as contact grips and friction pads. They climb in three different ways: scrambling/climbing using legs, tail and chin for example, through scrub and up rocks; gripping with limbs around an object, like a person climbing a pole; or like a possum with just the claws doing the gripping.
Can Tasmanian devils swim?
Tasmanian devils are capable of swimming but do so very low in the water, with only their head exposed. However, if they have young in the pouch, they avoid swimming for more than very short distances. Tasmanian devils love water and will wade and splash about, even sitting or lying down in it to stay cool. They will often dabble in water with their front paws.
How fast can Tasmanian devils run?
On rough terrain Tasmanian devils can run faster than a person; on very smooth terrain they cannot run as fast as a good human runner. Tasmanian devils have been ‘clocked’ running on a flat road at nearly 25 km/h for up to 1 km. They can run at 10 km/h for many kilometres.
Why do they make so much noise?
The Tasmanian devil has at least eleven distinct vocalizations, which include; ‘snort’, ‘hump-growl’, ‘bark’, ‘clap’ (snapping of the jaws), ‘growl-whine’ (with three stages monotone-vibrato-crescendo), ‘screech’ and ‘sneeze’. They also snore and sigh. Many of these vocalizations are bluff and part of a ritual to intimidate other animals in order to avert a fight when feeding communally at a large carcass. Powerful animals like the Tasmanian devil often have sophisticated mechanisms to avoid fighting so they do not damage themselves. The sound helps to resolve the pecking order. They start an encounter with another devil with a ‘humf-growl’, sniffs and snorts, and if the encounter becomes aggressive this escalates into screeches that increase dramatically until it’s a crescendo of screaming. At a carcass where a number of devils are attempting to feed, vocalizations help to establish order from the apparent chaos.
Why are their ears red?
The ears are sparsely furred, with very thin skin. When they are stressed or very excited the ears flush with blood, making them appear red.
Why do they yawn?
The famous gape or yawn of the Tasmanian devil that looks so threatening, can be misleading. This display is performed more from fear and uncertainty than from aggression and is part of a displacement behaviour which means they redirect nervous energy to something that’s harmless.
How do they communicate?
As well as vocalizations, devils have a large range of body postures used to communicate with other individuals. When they are very excited, the hair on their tails is raised. The tail can be held in many positions in combination with other body postures, and the subtleties probably have much meaning in communicating the animal’s level of arousal or aggression to other devils.
How much can they eat?
If they are not interrupted, Tasmanian devils can eat up to 40 per cent of their body weight in 30 minutes, termed ‘gorge feeding’. This is an adaption to strong competition for food which allows the first devil at a carcass to dominate and take in a much as possible before being displaced by others that arrive later. Like other carnivorous animals, devils on average consume about 12% of their body weight per day in the wild so even a huge feast like that would only keep them going for three days.
Many predators eat large amounts, the main reason being that they may not get to eat again for some time. Basically, it is safer to have your food inside you rather than carry it around where it may be stolen.
What do they normally eat?
The Tasmanian devil is mainly a scavenger and feeds on whatever animal is available. Powerful jaws and teeth enable it to almost completely devour its prey including; bones, fur, skin, organs and offal. Native animals such as wallabies, possums and wombats are favourites while various small mammals and birds (and eggs) are also eaten - either as carrion or prey. Reptiles, amphibians, insects, fish and even sea squirts have been found in the stomachs of wild devils. Devils will also scavenge on beach washed whale and seal carcasses.
Carcasses of sheep and cattle provide food in farming areas. Generally dead cows can only have small bits eaten because the skin is too thick for Tasmanian devils, but they will enter a carcass at the orifices (or wounds) and eat them from the inside out. Whole sheep can be eaten except for the large bones. New born lambs are sometimes at risk and poultry that roosts on the ground are also vulnerable, however, most healthy stock is safe. Tasmanian devils maintain bush and farm hygiene by cleaning up carcasses of sick and dead stock. This can help reduce the risk of blowfly strike to sheep by removing food for maggots.
They are opportunists and prefer to eat carrion as they don’t have to expend energy in hunting, however, when there is little carrion they will actively hunt. Tasmanian devils are capable hunters and may use various techniques to capture prey, such as ambush, pursuit and antisocial hunting.
Why are some individual so dominant when feeding?
Basically, the most motivated (usually the hungriest) animals are the most dominant. If all individuals were of the same hunger level the largest one would likely be the most dominant and feed first. However, Tasmanian devils vary enormously in personality. Some individuals are very calm and tolerant, others are 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 so not motivated to fight over food.
Why do they have fat tails?
Most marsupials store fat in their tails and a fat tail is usually a sign that an animal is in excellent condition.
Do they injure each other?
Fighting – often superficial fighting without serious contact – is the basic mechanism for establishing pecking order and competing for food. Fighting in devils is ritualized so that in all but a few instances the animals avoid contact, therefore avoid injury and save energy. Many animals employ this strategy.
Devils injure each other very occasionally, mostly when they are fighting over mates or during mating. They rarely injure each other when fighting over food (only 6% of interactions over food lead to injuries).
Most Tasmanian 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 other males for access to females. Some wounds are from shards of bone cutting them as they crunch through it.
Some devils have scars on the rump which are mainly caused when animals back into other animals to try and push them away from food. It is safer to be bitten on the thick-skinned rump than on the face. Similarly, they get bitten after aggressive encounters where the loser turns and flees and the victor snaps at their rump. Scars on the nape of the neck usually indicate the animal is a female. The scars are caused by males holding the female to subdue them during mating. Males hold females by the nape and will drag them to dens for mating. As the breeding season approaches sexually mature females develop a fat pad under the nape to help protect them from injury.
Do they have predators?
In the past thylacines were no doubt predators of Tasmanian devils. Young Tasmanian devils (or imps) are sometimes active during the day and in doing so are at risk from birds of prey such as eagles. As very small imps, if they become separated from their mothers, they are at risk at night from large owls and quolls. Almost certainly large Tasmanian devils will eat imps if they encounter them. Imps can climb well and this possibly helps them to escape from large predatory Tasmanian devils.
Why are some individuals wary and others confident?
Like people or other animals, Tasmanian 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 traumatised or hurt will be wary. Tasmanian devils can have different fathers within the same litter, therefore personality traits can vary because of different genetic traits. As a general rule devils are very wary and that’s why they are difficult to see.
Do they come out in the day?
In the wild Tasmanian devils are nocturnal (active after dark) particularly in areas frequented by people. In wilderness areas they do come out in daylight to forage, for example, along beaches following high tides as they scour the tide line for food.
During the day they usually retreat to a den or dense bush. Where they are not harassed by people or dogs, devils love to discreetly sun bake. Devils of all ages do this. Devil imps have been seen out sunning themselves together with lizards, which they would usually eat, Young weaned devils are “crepuscular” coming out at dusk and dawn in the twilight. Don’t be fooled by the devil, they are around even when you don’t see them. Often the only evidence will be their scats or tracks which you have to actively search for.
What controls their numbers?
The greatest current threat to numbers across Tasmania is Devil Facial Tumour Disease (DFTD). It is a fatal condition, restricted to Tasmania devils, that is characterised by cancers generally around the mouth and head. In 1996, Tasmanian devils were first photographed in north-east Tasmania with large tumours on their faces. Since then there has been a 95 per cent decline of average spotlighting sightings in that region, and a drop of 80 per cent across most of the State.
Devil numbers were drastically affected by the arrival of Europeans in Tasmania. Early settlers persecuted devils as sheep killers and the Tasmanian government offered a bounty to encourage landowners to kill thylacines and no doubt devils were bycatch. Van Diemans Land Company offered bounties for both thylacines and devils in 1830. Persecution has continued sporadically even following the cessation of bounties.
In the past, competition, and perhaps predation from thylacines, would partly control Tasmanian devil numbers. Other factors affecting numbers included food availability, competition from other devils and quolls, the loss of den sites to development, rodenticides and the toll of road strike.
Do they have diseases and parasites?
Tasmanian devils carry several internal and external parasites. They often have small numbers of ticks, round worms, tapeworms, and other parasites. Devils carry a unique tapeworm (Dasyurotaenia robusta) that is also listed as a threatened species along with its host. Very old devils often present with lymphoma, and a range of other non-cancerous tumours.
Degenerative neurological disease is often seen in old devils causing spinal deterioration leading to crippling of the hind limbs. Of greatest concern now is DFTD.
What are they related to?
Tasmanian devils are most closely related to quolls and there are believed to be several fossil devils species extending as far back as the Miocene epoch (5- 23 million years). A very early devil species of this era was Whollydooleya tomnpatrichorum, from the Riversleigh World Heritage Area fossil deposits in north Queensland, that may have weighed twice as such as the living devil. One species from the Pleistocene (aged at 50,000 -70,000 years), Sarcophilus laniarius were up to 15% larger and 50% heavier than modern devils.
Their next closest relationship is with smaller marsupials and a more distant relationship is with thylacines. They are marsupials so are only distantly related to placental animals such as dogs. Their similarity to other mammals, such as dogs, is an example of convergent evolution, where species that are only very distantly related share physical characteristics. In nature, certain body forms have proven to be efficient solutions to the problem of survival, so these forms are repeated.
What does their Latin scientific name mean?
Their Latin name is Sarcophilus harrisii. That means Harris’ meat lover. Deputy Surveyor General George Harris provided the first scientific description of the species.
Are Tasmanian devils dangerous to people?
No, Tasmanian devils are not dangerous. They do not attack people, although they will defend themselves if attacked, cornered or trapped. Despite their appearance they are very timid, quiet animals that would much rather run away than fight. However, devils have very powerful jaws and any bite could cause serious injury. Tasmanian devils are wild animals and therefore should be treated as such.
Do they form packs?
Tasmanian devils do not form packs – a pack being an organised group of animals of the same species. Large numbers may hunt in the same area and may even hunt the same animal, but they do not do this in an organised manner. Even so, the confusion they cause may give them an advantage over the prey as they know where each other is from the sniffs and snort sounds and contact calls which allows them to move around the bush hunting as an “unco-ordinated” group.
Are they territorial?
Strictly speaking, they are not territorial. A territory is a defended core of home range. Tasmanian devils have fixed home ranges and a small mobile territory they carry with them. That is, they defend a small area of personal space. There is much we do not understand about how Tasmanian devils arrange themselves in the landscape.
How far do they travel?
GPS satellite tracking has shown that many Tasmanian devils will travel up to 16 km in one night within their home range. They do not repeat the same movements every night. If they find food early, they may not travel very far at all. We are not yet sure how far immature animals disperse from their mothers.
Tasmanian devils roam considerable distances along well-defined trails in search of food. They usually amble slowly, with a characteristic gait, but can gallop quickly moving both hind feet together.
Were devils always in Tasmania?
Remains of species of Tasmanian devils, including some very large ones, have been found in fossil deposits across much of mainland Australia. Certainly, devils have been isolated in Tasmania for at least 12,000 years, almost certainly devils were in Tasmanian before this as fossil evidence shows their presence in much of mainland Australia around 50,000 -70,000 years ago.
Were they in any other place than Tasmania?
Tasmanian devils once occurred on mainland Australia and may have been in Papua New Guinea also.
It is believed the devil became extinct on the mainland some 3000 years ago – long before European settlement. While it is not known exactly what happened to the devil on the mainland, it is likely that devils became extinct there due to a changing climate towards aridity and the spread of the dingo which was prevented from reaching Tasmania by a rise in sea level that created Bass Strait..
Were Tasmanian devils always considered an icon?
Today the devil is a Tasmanian icon but this hasn’t always been the case. They were considered a nuisance by early European settlers of Hobart Town, who complained of raids on poultry and sheep. In 1830 the Van Diemen’s Land Co. introduced a bounty scheme to remove devils, as well as Tasmanian tigers and wild dogs, from their northwest properties: 2/6 (25 cents) for male devils and 3/6 (35 cents) for females.
For more than a century, devils were trapped and poisoned, and they became very rare, seemingly headed for extinction. But the population gradually increased after they were protected by law in June 1941. During 1996 it became evident that Tasmanian devils were again under threat - this time from DFTD.
How many live in Tasmania?
It is very difficult to give an exact answer, with numbers thought to be within the range of 10,000 - 100,000 individuals. There are a variety of reasons why it is difficult to be more precise. One of the biggest challenges is that there are population number estimates for only a few places across the State – most of which were chosen for trapping because they were in high density before Devil Facial Tumour Disease. Good estimates for the Tasmanian Wilderness World Heritage Area, for instance, aren’t available because access is difficult and few surveys have been conducted.
Why are Tasmanian devils active during the day in zoos?
They have learnt in zoos that neither people nor anything else will harm them in the day and that is when they are also fed so people can see them. They may also become bored and interacting with people provides some stimulus.
Why aren’t they scared of artificial lights?
They actually are a little scared of artificial lights at first, but eventually realise that the light is not going to harm them. When other devils are about, they are more concerned with competition.
What use are Tasmanian devils?
Tasmanian devils have enormous value. They are fundamental to our ecology at the top of the food chain. As scavengers they play a vital role as nature’s auditors, removing sick, slow, diseased and dead animals from the landscape.
Tasmanian devils are a very important line of defence against introduced animals, particularly feral predators like cats, foxes and ferrets, species which are devastating to native wildlife.
Tasmanian devils are intrinsic to the Tasmanian psyche, and an icon of wild Tasmania. They are a great example of wildlife succeeding against all manner of pressures, a true ‘Aussie battler’. They attract visitors to the State and are the most popular exhibits at wildlife parks..
If there are still thousands of Tasmanian devils left in the wild, then how can they be classified as ‘endangered’?
There has been a decline across Tasmania of more than 80% in trapping surveys and in average sightings per spotlighting survey since DFTD emerged. Due to this alarming rate of decline, the Tasmanian devil has been listed as Endangered under Tasmania’s Threatened Species Protection Act 1995, as well as the Commonwealth’s Environment Protection and Bio-diversity Conservation Act 1999. The Tasmanian devil has also been listed as Endangered on the Red List of the International Union for the Conservation of Nature and Natural Resources (IUCN) – the benchmark for the global conservation status of plant and animal species.
It’s hard for us to know exactly how many Tasmanian devils remain in the wild, but our best estimate is thousands of mature individuals. One of the reasons why it’s difficult to be more precise is that there are population number estimates for only a few places across the state. Good estimates for remote areas are hard to obtain because of the difficult access. As with all our information, we are reviewing these figures as we learn more, so they may change.
Why is it so important that Tasmanian devils don’t become extinct in the wild?
We are already seeing the early signs of changes in the landscape from the decreasing devil population impacting on our agricultural industries as well as our environment. The decline in devil numbers means there are now large amounts of surplus carrion in the landscape (up to 100 tonnes/day) and other carnivores are already responding to that surplus.
One of the biggest threats is posed by introduced, invasive species – such as feral cats and dogs - which now have an opportunity for major expansion. Introduction of other predators such as foxes pose an even greater threat with reduced devil numbers as there is an open niche into which foxes could readily expand. It is important that we protect against such unwanted introductions and manage existing introduced predators to protect our vulnerable small animal species.
Devils eat a variety of insects, amphibians, reptiles, birds and mammals. If they are not present to prey on them, the result could be changes in the abundance of these prey species which may in turn effect the balance of plant and animal species. Interconnectivity in ecological systems means that there will be a flow on effect if the numbers of one species is significantly reduced.