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Catiana
July 16th, 2007, 02:45 PM
TASMANIAN DEVIL

The Tasmanian devil cannot be mistaken for any other marsupial. Its spine-chilling screeches, black color, and reputed bad-temper, led the early European settlers to call it The Devil. Although only the size of a small dog, it can sound and look incredibly fierce.

Description

The world's largest surviving carnivorous marsupial, the devil has a thick-set, squat build, with a relatively large, broad head and short, thick tail. The fur is mostly or wholly black, but white markings often occur on the rump and chest. Body size also varies greatly, depending on the diet and habitat. Adult males are usually larger than adult females. Large males weigh up to 12 kg, and stand about 30 cm high at the shoulder.

Distribution

Devils once occurred on mainland Australia, with fossils having been found widely. Today, however the devil is only found in Tasmania. It is believed the devil became extinct on the mainland some 600 years ago -- before European settlement of the continent. The dingo, which was brought into Australia by Aboriginal people, is believed to have ousted the devil from the mainland.
Today, devils are found in some north, east and central districts where some farming practices (e.g. rangeland sheep grazing) provide much carrion. Tasmanian devils may be seen in many rural and wilderness areas by slowly driving at night along secondary roads. Devils may be seen at the Narawntapu National Park, Mt. William National Park, Cradle Mt. National Park, the Arthur River and highland lakes area. Look for them a few hour hours after sunset.

Habitat

Devils are widespread in Tasmania from the coast to the mountains. They live in coastal heath, open dry sclerophyll forest, and mixed sclerophyll-rainforest -- in fact, almost anywhere they can hide and find shelter by day, and find food at night.

Breeding

Devils usually mate in March, and the young are born in April. Gestation is 21 days. More young are born than can be accommodated in the mother's backward-opening pouch, which has 4 teats. Although 4 pouch young sometimes survive, the average number is 2 or 3. Each young, firmly attached to a teat, is carried in the pouch for about 4 months. After this time the young start venturing out of the pouch and are then left in a simple den - often a hollow log. Young are weaned at 5 or 6 months of age, and are thought to have left the mother and be living alone in the bush by late December. They probably start breeding at the end of their second year. Longevity is up to 7-8 years

Diet

The devil is mainly a scavenger and feeds on whatever is available. Powerful jaws and teeth enable it to completely devour its prey -- bones, fur and all. Wallabies, and various small mammals and birds, are eaten -- either as carrion or prey. Reptiles, amphibians, insects and even sea squirts have been found in the stomachs of wild devils. Carcasses of sheep and cattle provide food in farming areas. Devils maintain bush and farm hygiene by cleaning up carcasses. This can help reduce the risk of blowfly strike to sheep by removing food for maggots.
Devils are famous for their rowdy communal feeding at carcasses -- the noise and displays being used to establish dominance amongst the pack.

Behavior

The devil is nocturnal (active after dark). During the day it usually hides in a den, or dense bush. It roams considerable distances --up to 16 km -- along well-defined trails in search of food. It usually ambles slowly with a characteristic gait but can gallop quickly with both hind feet together. Young devils are more agile however and can climb trees. Although not territorial, devils have a home range.
The famous gape or yawn of the devil that looks so threatening, can be misleading. This display is performed more from fear and uncertainty than from aggression. Devils produce a strong odor when under stress, but when calm and relaxed they are not smelly. The devil makes a variety of fierce noises, from harsh coughs and snarls to high pitched screeches. A sharp sneeze is used as a challenge to other devils, and frequently comes before a fight. Many of these spectacular behaviors are bluff and part of a ritual to minimize harmful fighting when feeding communally at a large carcass.

Status

Devils were a nuisance to the early European settlers of Hobart Town, raiding the poultry yards, but were soon driven away to more remote areas of the island. 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. Devils ate animals caught in snares, and were believed to take lambs and sheep. For over a century they were trapped and poisoned and became very rare. They seemed, like the Tasmanian tiger, to be headed for extinction. Despite this the Tasmanian devil was not protected by law until June 1941. After this the population gradually increased and the Tasmanian devil was chosen as the symbol of the Tasmanian National Parks and Wildlife Service.

Devil Disease:

A devastating disease is sweeping through Tasmania's devil population, killing more than 90% of adults in high density areas and 40-50% in medium-low density areas. The Devil Facial Tumor Disease, which is now having a devastating effect on the Tasmanian devil population was first noticed in the north-east of Tasmania in the mid-1990s but has become more prevalent in recent times in other areas of the State. The Tasmanian devil is now listed as vulnerable in Tasmania.

Shanti
July 16th, 2007, 02:52 PM
Wow I always liked devils but didnt know even a fraction of what you provided here.
I never had a clue they had that disease thats lowering their numbers.
Do you know if they have found any way to control it or cure it as of late?

Catiana
July 16th, 2007, 03:40 PM
The last thing I heard about it, is they are considering moving the healthy one to an island that has no Devil population, but I don't know how that is coming, I'll try to find some info on it.

Shanti
July 16th, 2007, 03:53 PM
The last thing I heard about it, is they are considering moving the healthy one to an island that has no Devil population, but I don't know how that is coming, I'll try to find some info on it.
I just wonder if they dont find away to stop this disease or if the animals don't become resistant, they will eventually be gone from the wild since their range is so limited on the planet. :(

Do you know if they even know the cause of this illness?

Catiana
July 16th, 2007, 03:59 PM
Here is an article from April of this year about the relocation.

http://blogs.usatoday.com/ondeadline/2007/04/tasmanian_devil.html

Shanti
July 16th, 2007, 04:04 PM
Thanks cat.
I found the Save the devi (http://www.tassiedevil.com.au/index.html)l site from your link!! :)

Shanti
July 16th, 2007, 04:05 PM
Here is a link to the latest developments. (http://www.tassiedevil.com.au/disease.html)

I started to read but the graphics were so terrible, I started to cry and had to stop reading.

Catiana
July 16th, 2007, 04:08 PM
Here is some additional information about the disease

Devil Facial Tumor Disease is a term used to describe a fatal condition in Tasmanian devils which is characterized by the appearance of obvious facial cancers. The tumors or cancers are first noticed in and around the mouth as small lesions or lumps. These develop into large tumors 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 may have many cancers throughout the body.

As the cancers develop in affected devils, they may become emaciated, particularly if the tumors interfere with teeth and feeding. Many females lose their young. Affected animals appear to die within six months of the lesions first appearing.
What effect is the disease having on devil populations?

In 1996, Tasmanian devils were photographed in the north-east of the State with what appeared to be large facial tumors – characteristics consistent with what is now known as Devil Facial Tumor Disease. As at December 2006, the Tasmanian devil disease had spread to 57 separate sites covering 56% of the State.¶¶Across Tasmania, there has been a 41% decline in average sightings from 1992-95 to 2002-05. In the north-east region, where signs of the Tasmanian devil disease were first reported, there has been a 90 per cent decline of average spotlighting sightings from 1992-95 to 2002-05. The proportion of animals displaying signs of the disease at any one site has reached up to 83% of trapped adults. The latest research indicates that the disease is transmissible between devils, so new cases continue to occur in areas where the disease had not previously been recorded. These sites include Lake Pedder, in the southwest, and approximately 30km west of Pencil Pine, near Mt Cattley. To date Narawntapu National Park has not been affected, but the Tasmanian devil disease is possibly getting close. Thankfully, as at December 2006, populations in the western third of the State remain healthy and viable. While it is uncommon for wildlife diseases to lead directly to population extinction in the absence of other severe threats, the Tasmanian devil disease is a new, unusual disease and there is no hard evidence for population or individual resistance or recovery from the disease. There is also a concern that if the population is diminished, while numbers of the introduced fox increase, it may be difficult for them ever to recover.

What is being done about the disease?

A research program, which has become known as the Devil Facial Tumor Disease (DFTD) Program, or more simply the Devil Disease Program, has been established to investigate the disease and identify management options. Coordinated by the Department of Primary Industries and Water (DPIW), it involves researchers and experts from a range of institutions, including University of Tasmania, University of Queensland, University of Sydney, Murdoch University, and wildlife parks and zoos.

The program is focused on the key areas of:

• Population monitoring - Gathering data in the field to clarify disease distribution and impacts, and to help determine conservation strategies.
• Disease diagnostics - A laboratory-based investigation of the disease itself, which includes defining the disease, exploring its transmission, the possible causes, and so on.
• Wild management - Establishing methods for managing the impact of the disease in the wild.
• Captive management – A captive breeding population with ‘founders’ taken from areas of the State where there hasn’t been any record of the disease.
To streamline management, a new high-level Steering Committee for the Project has been established. It is assisting the flow of information to the wide range of groups interested in the disease. The new structure consists of a Steering Committee (involving representatives of DPIW, University of Tasmania, Australian Wildlife Health Network and the Australian Government) and a Stakeholder Reference Group (including eco-tourism, farmers, wildlife park operators, RSPCA, Parks and Wildlife Service, veterinary and scientific representatives). Both of these groups are able to provide proper scrutiny to the program, and also to support and promote the work of the devil disease team.

Population monitoring

To improve our knowledge of the disease, DPIW Wildlife Biologist Clare Hawkins and DPIW Scientific Officers Billie Lazenby and Jason Wiersma have been maintaining devil monitoring sites across Tasmania. This data helps us to understand the spread of the disease and its impact on wild populations. Results as at December 2006 indicate that populations remain healthy and viable in the western third of the State. But with research indicating the disease is transmissible, new cases continue to occur in areas where the disease had not previously been recorded. Monitoring is also continuing at various sites where the disease has been known for long periods. This will provide information on the long-term impacts of the disease and its persistence in populations. In collaboration with scientists from CSIRO and Landcare Research (in New Zealand), the monitoring team is incorporating this information in predictive models of the devil population and disease changes, to identify key factors affecting these changes, and to guide the planning of disease control strategies in wild populations. . The specially developed traps are checked on a daily basis and animals are carefully examined by veterinary officers for signs of the disease before being released back into the wild.

Innovations

With necessity being the mother of invention, the on-going field work has delivered exciting innovations that help monitor devils.
Remote sensor cameras are being used as a monitoring tool, and are particularly valuable in hard-to-access areas. They’re also good to use in low-density devil populations, where the effectiveness of physical trapping is limited.

The new technology, developed by DPIW Scientific Officer Jason Wiersma, consists of a digital camera triggered when an infra-red sensor picks up the movement of an animal. Devils are lured into the area by bait placed at the site in an impenetrable container.


Meanwhile the PVC poly-trap, developed for catching devils in the wild by DPIW’s Wildlife Biologist Nick Mooney, gained national praise when Nick appeared on ABC TV’s New Inventors program. His purpose-designed trap, which provides a less stressful environment for the temporarily-caged animals, was voted the People’s Choice Award.

Disease diagnostics

In the laboratory, researchers have collected and examined blood, tissue and tumor samples from hundreds of devils to build up a detailed knowledge bank on the disease. The aim is to identify the origin of the cancer cells, as this can give clues to the cause. In collaboration with Murdoch University, the results of their work into the origin of the tumor cells were published in the November 2006 edition of Veterinary Pathology . Their research supports the hypothesis that the tumor cells are of neuroendocrine origin. In the same edition of Veterinary Pathology , staff from DPIW also published a case definition of the disease. Earlier this year research by members of the team on the genetic make-up of the tumor cells was published in the international journal Nature . The research indicated that the method of transmission of the disease between animals was consistent with direct animal to animal transfer. Meanwhile leading wildlife mathematical ecologist, Professor Hamish McCallum, has been appointed as Senior Scientist with the project. Formerly from the University of Queensland, Professor McCallum commenced at the University of Tasmania in October. A leader in the field of wildlife epidemiology, his role will include integrating the many lines of research into the disease that are occurring at a range of institutions.

Captive Management

In April 2007, Currumbin Wildlife Sanctuary announced that one of the Tasmanian devils from our captive breeding 'insurance' population was carrying up to four young in its pouch. Two shipments of 'Project Ark' animals – 48 Tasmanian devils in total – were sent to four mainland wildlife parks during December 2006 and January 2007. Interstate parks were chosen because of the mainland’s freedom from the Tasmanian devil disease. Animals in the insurance population, gathered from areas of the State where there has not been evidence of the disease, are spending a further year in quarantine in their new homes. While the news of the breeding success in Currumbin is encouraging, still more needs to be done to benefit conservation of the Tasmanian devil. So 31 young Tasmanian devils have been captured from north-west Tasmania, from areas that still seems to be free of the disease, to be used in one or other 'insurance' strategy. It has not been decided as yet what will be done with these devils. The possibility of establishing a population on one of Tasmania's offshore islands is currently being investigated. As there are currently no Tasmanian devils on any of the islands, the strategy requires careful assessment of all potential risks, as well as potential benefits.

Shanti
July 16th, 2007, 04:08 PM
Link in post #7
there has been a 53% decline in average sightings from 1992-95 to 2003-06. In the north-east region, where signs of the Tasmanian devil disease were first reported, there has been a 89% decline of average spotlighting sightings from 1992-95 to 2002-05.
It is uncommon for wildlife diseases to lead directly to population extinction in the absence of other severe threats. But as at December 2006, there had not been any evidence of population or individual resistance or recovery from the diseaseThe over all pop sightings has fallen by 53%
In some areas as much has 89%

So sad.

It looks like desperate times to save them.

I dont care what they try.
It looks like if they do nothing, the world will see the wild devils disappear.

Catiana
July 16th, 2007, 04:19 PM
Yes, I'm afraid that is too, I think the only real hope is that the relocatin plan becomes a reality and then the healty devils can re-populate. At least I hope that's what can happen.

Shanti
July 16th, 2007, 04:22 PM
Yes, I'm afraid that is too, I think the only real hope is that the relocatin plan becomes a reality and then the healty devils can re-populate. At least I hope that's what can happen.
I just wonder if what caused it may happen again?
The cause is always so important to discover.

Willow Rosette
July 16th, 2007, 04:56 PM
Oh this is so sad. Thank you both for all the information and links.

Catiana
July 16th, 2007, 06:33 PM
I just wonder if what caused it may happen again?
The cause is always so important to discover.



you're absolutely right about that. I hope they can find the answers before its too late for the Devils.

Catiana
July 19th, 2007, 05:10 PM
bump