Not Just a Cartoon Character

From Australian Geographic

The Tasmanian Devil is known to many in the cartoon world as the Warner Bros.’ aggressive Looney Tunes cartoon character Taz, but that is not all there is to this creature (5). The Tasmanian Devil, Sarcophilus harrisii, is a carnivorous marsupial. In fact, it is the largest carnivorous marsupial in the world, approximately 30 inches long and 26 pounds, according to National Geographic (1). The Tasmanian Devil did not become the largest carnivorous marsupial in the world until the mid-1930’s when the previous title holder, the Tasmanian wolf or tiger (thylacine), was hunted to extinction (4).

The Tasmanian Devil was first described in 1808 by George Harris (4) and is in the class Mammalia and the family Dasyuridae, which includes other marsupials that are native to Australia as well as New Guinea. (2). Dasyurids are set apart from other marsupials in Australia because of a couple of characteristics. According to The University of Edinburgh, dasyurids’ lower jaw contains three pairs of incisors and their feet have five toes (6).

Range and Habitat
The Tasmanian Devil is native to Australia’s island of Tasmania, though they once roamed most of Australia’s mainland about 400 years ago (7). Many speculations have been made for this decrease in range. The most common speculation for the extinction of Tasmanian Devils on the mainland of Australia is that it could have been caused by the introduction and increased distribution of the dingo (1). The dingo not only became a predator to the Tasmanian Devil, but also competed for the same food sources. Within Tasmania, they are most commonly found on the dry coastal scrub lands and coastal forests of the island, although they can be found anywhere on the island such as the mountains (3). During the day they can often be found hiding away caves or burrows once used by wombats or other animals.

Physical Description
The Tasmanian Devil has a black or brown coat of fur with white markings on its chest, shoulders, and rear end. They have very powerful jaws and sharp teeth (7). Even though Tasmanian Devils are the largest carnivorous marsupial in the world, they are fairly small, about the size of a small dog. According to the San Diego Zoo, they range in size from 23 to 26 inches long and they weigh in at about 11 to 30 pounds. These mammals have a thick tail that is about 9 to 10 inches long. Typically, adult males will be larger than females. Interestingly, their front legs are slightly longer than their back legs (3). When they are first born they are incredibly small, ‘about the size of a grain of rice’ (4). Tasmanian Devils reach maturity around the age of 2 years and have an expected lifespan of 5 to 8 years in the wild (4). The female Tasmanian Devil has a pouch with four teats on her underside where her babies, also called imps, will stay for 4 months (3).

Ecology
The Tasmanian Devil is nocturnal, often feeding at night and traveling upwards of 10 miles (7). During the day they hide away in their dens, keeping safe from predators (1). Once an adult devil finds a suitable den, they typically remain in that same den for the rest of their life. When a den gets destroyed, this can be detrimental to the population. The devil shares den and diet interests with the local red fox population, which causes some competition between the two species. However, this has not caused any noticeable effects on either population (9).

In general, Tasmanian Devils are very solitary creatures, except when feeding on a large carcass where there are usually multiple devils feasting at a time. The Tasmanian Devil is carnivorous and enjoys munching on fish, insects, birds, and reptiles and amphibians. Though they sometimes catch prey, they are mostly scavengers and will eat everything can, including the bones and fur (1). They even feed on carcasses of large farm animals, which is appreciated by the farmers because it keeps the fly populations down (10). When they do go on the hunt, they use ambush and chasing tactics to catch prey even 44 pounds in size (9).

Behavior
As the cartoon character Taz displays, Tasmanian Devils can be pretty fierce and intimidating. When threatened, they let off harsh noises that sound like coughs, screeches, and growls. Even though they sound aggressive, the fierce noises are more for a warning or a display of fear rather than aggression (10). They do still become aggressive with each other though, often biting each other, even until death. Along with these harsh warnings, the Tasmanian Devil also releases a foul odor when it is in a stressful situation (7).

After a three week gestation period, a female Tasmanian Devil gives birth to about 20 to 30 imps, but unfortunately only 4 of them will survive because the mother only has 4 teats within her pouch to feed her young (1). After leaving the pouch, the imps are carried on their mother’s back (3). At eight months old, the baby devils are on their own (1).

When hunting, Tasmanian devils can travel long distances each night. On average, they travel just under 6 miles a night, but they have been found to travel up to 30 miles in a single night just to find food. The Tasmanian devil’s home range can be anywhere from 2-17 mi2 within a two-four week period according to the IUCN Red List (9).

Conservation Status
The Tasmanian Devil is listed by The IUCN Red List of Threatened Species as an endangered species, with many factors contributing to that status (9). The biggest threat that this species faces is the Devil Facial Tumor Disease, or DFTD, an infectious cancer that was detected in 1996 (4). In this disease the tumor cells are what cause the infection and the spread of the infection to other Tasmanian Devils. It is transmitted from one animal to another usually when they bite each other. A paper about the biting behavior of Tasmanian Devils and its relation to DFTD showed that the dominant devils that bite other devils’ tumors are more likely to contract the disease than the devils that are bitten by these dominant devils. This paper also determined that each population that was observed had similar biting rates, which concluded that the biting rates could not explain the degree of impact this disease had on different parts of Tasmania (8). This disease will kill the infected devil with 6 to 12 months according to San Diego Zoo. Unfortunately, neither a cure nor a vaccine has been discovered yet (4). Since 2001, the population has decline 60 percent due to this disease (3).

Other factors contributing to the decrease in devil numbers are road-kills and other predators. These don’t have as detrimental of an impact as the Devil Facial Tumor Disease but still have a recognizable impact. The IUCN Red List of Threatened Species states that approximately 2,205 Tasmanian devils lose their lives on roadways each year (9). Many initiatives have been put in place by various organizations to save these unique animals. The most prominent effort is the Save the Tasmanian Devil Program that was created by the governments of Tasmania and Australia (10).

References:
(1). Tasmanian Devils, Tasmanian Devil Pictures, Tasmanian Devil Facts – National Geographic. (n.d.). Retrieved November 20, 2014, from http://animals.nationalgeographic.com/animals/mammals/tasmanian-devil/

(2). Myers, P. (2001, September 19). Dasyuridae (dasyurids). Retrieved November 21, from http://animaldiversity.ummz.umich.edu/accounts/Dasyuridae/

(3). Bradford, A. (2014, October 23). Facts About Tasmanian Devils. Retrieved November 20, 2014, from http://www.livescience.com/27440-tasmanian-devils.html

(4). Mammals | Tasmanian Devil. (n.d.). Retrieved November 20, 2014, from http://animals.sandiegozoo.org/animals/tasmanian-devil

(5). Taz the Tasmanian Devil | Looney Tunes Characters | Boomerang TV. (n.d.). November 20, 2014, from http://www.boomerangtv.co.uk/shows/looney-tunes/characters/taz

(6). DASYURIDS: MARSUPIAL CARNIVORES. (n.d.). Retrieved November 21, 2014, from http://www.nhc.ed.ac.uk/index.php?page=24.134.165.255.261

(7). Tasmanian Devil, Sarcophilus harrisii. (n.d.). Retrieved November 21, 2014, from http://www.parks.tas.gov.au/?base=387

(8). Hamede, R. K., McCallum, H., Jones, M. (2013), Biting injuries and transmission of Tasmanian devil facial tumour disease. Journal of Animal Ecology, 82: 182–190. doi: 10.1111/j.1365-2656.2012.02025.x

(9). Hawkins, C.E., McCallum, H., Mooney, N., Jones, M. & Holdsworth, M. 2008. Sarcophilus harrisii. The IUCN Red List of Threatened Species. Version 2014.3. . Downloaded on 21 November 2014.

(10). Latest News (also see our newsletters). (n.d.). Retrieved November 21, 2014, from http://www.tassiedevil.com.au/tasdevil.nsf

(11). Picture: Hanson, J. (2012, February 20). Tasmanian devil genome offers cancer clues. Retrieved November 21, 2014, from http://www.australiangeographic.com.au/news/2012/02/tasmanian-devil-genome-offers-cancer-clues/