The world's largest surviving carnivorous marsupial, the Tasmanian 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 and can weigh up to 12 kg and stand about 30 cm high at the shoulder. In the wild Tasmanian devils live up to six years.
Tasmanian devils Lilo and Stitch having a cuddle
copyright: Linda Nichols
Tasmanian devils once occurred on mainland Australia, with fossils having been found widely, but 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 aridity, changing climate and the spread of the dingo and possibly disease which was prevented from reaching Tasmania by Bass Strait.
Today the devil is a Tasmanian icon but this hasn’t always been the case.
Tasmanian devils were considered a nuisance by early European settlers of Hobart Town, who complained of raids on poultry yards. 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 Devil Facial Tumour Disease (DFTD)
Despite the decline in numbers since the detection of DFTD in the 1990s, populations of Tasmanian devils remain widespread in Tasmania from the coast to the mountains. They live in coastal heath, open dry sclerophyll forest, and mixed sclerophyll-rainforest. Devils also take advantage of the interface between native habitat and agricultural paddocks, where their favourite prey species are often found.
Devils usually mate between February and May, and after a gestation period of 21 days the young are born. More young are born than can be accommodated in the mother's pouch which has four teats.
Although four pouch young sometimes survive, the average number is two or three. Each young, firmly attached to a teat, is carried in the pouch for about four 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 five or six months of age, and have usually left their mother to live alone by late December. These young then typically start breeding at the end of their second year.
Tiny Tasmanian devil
copyright: Linda Nichols
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 one 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. 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.
The Tasmanian devil is a scavenger and a hunter feeding on whatever animal is available. Powerful jaws and teeth enable it to completely devour its prey - bones, fur and all. Native animals such as wallabies, possums and wombats are favourites. 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. Tasmanian 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.
The Tasmanian devil is nocturnal (active after dark). During the day it usually hides in a den, or dense bush. They roam considerable distances - up to 16 km in one night- along well-defined trails in search of food. Devils usually amble slowly with a characteristic gait but can gallop quickly with both hind feet together. Young Tasmanian devils are more agile than adults and can climb trees. Although not territorial, devils have a home range which can be very large if resources are scarce.
Tasmanian devils are also very good swimmers, however if they have young in the pouch they avoid swimming for more than very short distances. Tasmanian devils actually 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, somewhat in the manner of racoons. Tasmanian devils will sometimes store food in water and can even take a breath and “duck dive”.
Tasmanian devil swimming
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. Tasmanian devils produce a strong odour when under stress, but when calm and relaxed they are not smelly. The Tasmanian 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 behaviours are bluff and part of a ritual to minimise harmful fighting when feeding communally at a large carcass.
Owen, D. & D. Pemberton (2005). The Tasmanian Devil; a unique and threatened animal. Allen and Unwin.
Pemberton, D., Gales, S., Bauer, B., Gales, R., Lazenby, B. & K. Medlock. (2008) The diet of the Tasmanian devil, Sarcophilus harrisii, as determined from analysis of scat and stomach contents. Papers and proceedings of the Royal Society of Tasmania. 142(2): 13-21.
Robert K. Rose, David A. Pemberton, Nick J. Mooney, Menna E. Jones; Sarcophilus harrisii (Dasyuromorphia: Dasyuridae), Mammalian Species, Volume 49, Issue 942, 1 May 2017, Pages 1–17.
Pemberton, D. & Renouf, D. (1993). A field study of communication and social behaviour of the Tasmanian devil at feeding sites. Aust J. of Zoology. 41: 507-526.
Rogers, T., Fox, S., Pemberton, D. & Wise, P. (2016) Sympathy for the devil: captive management style did not influence survival, body-mass or diet of Tasmanian devils 1 year after wild release. Wildlife Research, Journal Compilation CSIRO.
Menna E. Jones, Andrew Cockburn, Rodrigo Hamede, Clare Hawkins, Heather Hesterman, Shelly Lachish, Diana Mann, Hamish McCallum and David Pemberton Life-history change in disease-ravaged Tasmanian devil populations PNAS July 22, 2008. 105 (29) 10023-10027.