MARSUPIAL MICE AND CATS, TASMANIAN DEVIL: Dasyuridae

PHYSICAL CHARACTERISTICS

Members of the family Dasyuridae include marsupial mice and cats and the Tasmanian devil. Marsupials are animals that do not have a very well developed placenta. A placenta is an organ that grows in the mother's uterus (womb) that allows the developing offspring to share the mother's food and oxygen. Because of this, pregnancy in marsupials is short and the young are born undeveloped and unable to fend for themselves. After birth, the young move to the mother's pouch and attach to her milk teats (nipples) until they have finished developing enough to live on their own.

None of the members of the family Dasyuridae are very large. This order includes some of the world's smallest marsupials, members of the genus (JEE-nus) Planigale, some of which are less than 4 inches (10 centimeters) long and weigh less than 0.2 ounces (5 grams). Other members of this family vary in size up to the Tasmanian devil, which is the largest species. The Tasmanian devil can be up to 25 inches (62 centimeters) long and weigh up to 29 pounds (13 kilograms).

Marsupial mice and cats, as well as the Tasmanian devil, have four legs. They have four toes on each of their two front feet and either four or five toes on their two back feet. When they have five toes on their back feet, the fifth toe is a hallux (HAL-lux). A hallux is a toe that does not have a claw. The species in this family usually have pointed snouts and long tails.

The fur of animals in this family is mostly gray or brownish, and sometimes is black. Fur color often depends on the habitat in which the species lives, and the kind of fur that best camouflages them helps them avoid predators, animals that hunt them for food. Some of the species have other markings. The northern quoll has white spots on its otherwise brown body. The teeth of members of this family vary depending on the preferred diet, but most have some sharp teeth for slicing and biting and other wider, flatter teeth for grinding. This combination of teeth is helpful for catching and eating other animals and insects.

GEOGRAPHIC RANGE

Members of Dasyuridae live in Australia, New Guinea, and Tasmania, and can also be found on some small islands in that area of the Pacific.

HABITAT

Members of the family Dasyuridae live all over Australia, Tasmania, and New Guinea, and occupy all types of habitats. Some species live in trees, but most species are ground dwelling; some species prefer open grassland, and others prefer forests. Animals that have different habitats have different ways of finding or making dens and different ways of finding food.

TAZ

Tasmanian devils have a reputation around the world for being vicious destroyers of property thanks to a Warner Brothers cartoon character named Taz. Taz, a Tasmanian devil, spins like a tornado destroying everything in his path. He stands on his hind legs and has teeth that can crush through anything. Although Tasmanian devils do have sharp teeth and very strong jaw muscles, they do not stand on their back legs alone. Tasmanian devils can be vicious when they feel threatened, but do not spin and certainly cannot destroy entire forests!

DIET

What the members of this family eat depends on their size. The species that have smaller bodies, such as the marsupial mice, usually eat insects and sometimes catch and eat small animals such as lizards. These smaller animals will eat large animals only if they are already dead, in which case they will feed from the carcass. Larger species in this family eat mainly other vertebrates, or animals that have backbones, such as wallabies and birds. Species that eat mainly vertebrates will occasionally eat some insects and other invertebrates, animals without backbones, as well. Some species will even supplement their diet with food that does not come from other animals, such as flowers and fruit. All species in this family are scavengers when they get the chance. They will eat animals that are already dead, if they are available. Members of this family are usually nocturnal and hunt and are active mainly at night.

BEHAVIOR AND REPRODUCTION

Like all marsupials, species in this family give birth to young that are often blind and hairless, and are not able to survive on their own. This means that pregnancy for these species is usually very short. When the young are born, they either move into the mother's pouch or to her underbelly where they attach themselves to her teats. When attached in this way, the developing young travel with their mother for weeks or months as they continue to grow and develop. Once the young are able to survive on their own, they are weaned from their mother and detach from her nipples. After this, there is usually a period during which the young stay close to home and hunt away from their mother for increasingly long periods before going off on their own. The males of these species usually travel farther from the mother's nest to find territories of their own than the females do.

Some species in this family mate only one time before they die. The males of these species often die soon after mating, although the females live long enough to raise their young and sometimes to have a second litter. Scientists think that the reason that males of some species only mate once and then die is because it takes so much energy for the males to mate, especially in years when there is not much food available. Scientists think that these animals use up so much energy mating that they no longer have enough energy to stay healthy.

MARSUPIAL MICE, CATS, TASMANIAN DEVIL, AND PEOPLE

Members of this family usually do not have much direct interaction with people. Some species, however, have been thought to kill livestock and because of this have been hunted by farmers.

CONSERVATION STATUS

No species in this family are known to be extinct, but many, such as the Kangaroo Island dunnart, are Endangered. Animals that are considered Endangered face a very high risk of becoming extinct in the wild. Many other members of this family are Vulnerable, facing a high risk of extinction in the wild. There are some species in this family that scientists do not yet have enough information about to know if they are endangered or not.

BRUSH-TAILED PHASCOGALE (Phascogale tapoatafa): SPECIES ACCOUNTS

Physical characteristics: The brush-tailed phascogale has gray colored fur on its back and white or creamy fur on the underside of its body. Its brush tail is black with long, 2-inch (5.5-centimeter) hairs. Its body is 5.8 to 10.3 inches (14.8 to 26.1 centimeters).

Geographic range: Brush-tailed phascogales live in coastal areas of Australia.

Habitat: These animals live in dry eucalyptus forests and woodlands with an open understory—not a lot of smaller plants growing under the tallest trees—in temperate and tropical areas of Australia.

Diet: Brush-tailed phascogales feed on nectar (sweet liquid produced by plant flowers), large insects, spiders, and small vertebrates, animals with a backbone. They tear the bark off of trees to look for food.

Behavior and reproduction: This animal spends much of its time up in trees, and is nocturnal, or active at night. Brush-tailed phascogales make their nests in tree holes or forks, and also mate there. Females give birth to about eight young, who are attached to her nipples, feeding, for about forty days. After that, they stay in the nest until they're five months old.

Brush-tailed phascogales and people: These animals occasionally eat poultry raised by humans, but they also eat mice and insects, which humans may appreciate.

Conservation status: The brush-tailed phascogale is not currently threatened. ∎

TASMANIAN DEVIL Sarcophilus laniarius

Physical characteristics: The Tasmanian devil is a four-footed marsupial with four toes on its two front feet as well as four on its back feet. It does not have a hallux. It has black fur with some white markings, usually on the chest, shoulder, and rump. The Tasmanian devil has a pointed snout that is pinkish at the tip. Its sharp, pointed teeth are good for cutting and tearing meat. It also has flat grinding teeth for crushing the bones of the animals it eats. The ears of the Tasmanian devil are short and pointed and turn red when the animal is angry. Males of this species usually have a head and body length between 20 and 25 inches (50 to 62 centimeters) and weigh between 17 and 29 pounds (8 to 13 kilograms). Females usually have a head and body length between 21 and 22.5 inches (53 to 57 centimeters) and weigh between 10 and 20 pounds (4.5 to 9 kilograms).

Geographic range: Tasmanian devils live on Tasmania, a large island off the southeastern Australian coast.

Habitat: The Tasmanian devil lives in the forest. It makes dens using leaves and plant material, although it sometimes sleeps in hollow logs or in the dens of other animals.

Diet: The Tasmanian devil mainly eats the meat of vertebrate animals. It will even eat poisonous snakes, and also occasionally invertebrates or plants. It is mainly a scavenger, and likes to eat animals that have already been killed by other causes. A scientist who studied the Tasmanian devil found that its favorite foods were wallabies, wombats, sheep, and rabbits. Most of these animals were not hunted by the Tasmanian devil itself, but eaten after other animals, cars, or natural causes killed them. The Tasmanian devil makes use of all the parts of animals that it kills or finds, eating even the bones and fur.

Behavior and reproduction: The Tasmanian devil is nocturnal, meaning that it hunts and is active mainly at night. When Tasmanian devils feel threatened or are fighting, they can be very loud. They begin by growling softly, but become increasingly louder and can even make horrible screeching noises. Most mating occurs in February or March. Females are pregnant for about one month and then give birth to young that move into the mother's pouch and attach to her nipples. Female Tasmanian devils have four nipples, which means that four is the most young that can be supported while they develop. Tasmanian devils normally have two or four babies at a time.

Tasmanian devils and people: Most contact between humans and the Tasmanian devil has occurred because the Tasmanian devil may eat animals that farmers keep as livestock. The Tasmanian devil will eat chickens if the coops are not well protected, and also sheep and lambs. Farmers sometimes kill Tasmanian devils to keep them away from their livestock.

Conservation status: The Tasmanian devil used to live all over Australia, but now lives only in Tasmania. Scientists believe that this species disappeared from the Australian mainland because it had to compete with the dingo, a wild dog that is introduced, not a native species. There is no information on how many Tasmanian devils are left in the wild in Tasmania, but it is likely that they are being affected by the clearing of land for agriculture. ∎

FOR MORE INFORMATION

Books:

Fenton, Julie A. Kangaroos and Other Marsupials. Chicago: World Book, 2000.

Hoare, Ben, ed. International Wildlife Encyclopedia, 3rd ed. Tarrytown, NY: Marshall Cavendish, 2002.

Nowak, Ronald M., ed. Walker's Mammals of the World, 5th ed. Baltimore and London: Johns Hopkins University Press, 1991.

Woods, Samuel G. Sorting Out Mammals: Everything You Want to Know About Marsupials, Carnivores, Herbivores, and More! Woodbridge, CT: Blackbirch Marketing, 1999.

Web sites:

Tasmanian Department of Primary Industries, Water & Environment. Tasmanian Devil.http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/BHAN-5358KH?open (accessed on June 30, 2004).

Other sources:

"The Amazing Marsupials." Australian Ark Documentary Series. Columbia Tristar, 1994.