Numbat: Myrmecobiidae

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NUMBAT: Myrmecobiidae

PHYSICAL CHARACTERISTICS

Numbats, sometimes called banded anteaters, are small marsupial mammals that live in the southwestern region of Western Australia. Considered to be one of the most beautiful and distinctively marked marsupials, numbats are the only species of the Myrmecobiidae family.

Numbats are small, four-legged animals that are a little larger than rats. Weighing about 1 pound (0.45 kilograms), they range in total length from 12 to 19 inches (30 to 47 centimeters). Their tails can be 5 to 8 inches (13 to 20 centimeters) long. Their front feet have five toes and their back feet have four toes. All of the toes have strong claws to help them dig quickly for termites, their preferred food. They also have an extraordinarily long tongue that they use to gather the termites from underground and from holes in rotting trees. Unlike other marsupials, the female numbat does not have a pouch to carry her young, but she does have four nipples on her underside. The young cling to the nipples on her belly while they develop.

The numbat has coarse, short fur that varies in color from grayish brown to reddish brown. The numbat is distinctively marked with a series of five to seven white stripes that run across its rump and lower back. A black band bordered by two white bands runs on each side of the head from the snout through the eye and to the base of the ear. Their underside has paler fur and the fur on their tail is long.

GEOGRAPHIC RANGE

In the late eighteenth and early nineteenth century, when Europeans began to settle in Australia, numbats occupied a much larger area than they do today. At that time, numbats lived in the southern half of central and western Australia. They lived as far east as New South Wales and as far north as the Northern Territory. Today, numbats inhabit nine wild and two free-range areas across the southern region of Western Australia.

HABITAT

Numbats once lived in a variety of habitats from open forests to grasslands. Today they prefer areas with plenty of ground-level cover in order to protect them from the weather and predators such as hawks and red foxes. Numbats also use hollow logs and thickets to protect themselves from predators, animals that hunt them for food.

DIET

Numbats mainly eat termites—their pointed snouts allow them to sniff out the insects underground. They then use their sharp claws to dig small holes and retrieve the termites from underground tunnels using their long, slender tongues. The numbat's tongue can extend as much as 4 inches (10 centimeters) from its mouth. Saliva on the tongue makes the termites stick to it, so that the numbat can quickly pull its tongue back into its mouth with the termites attached. The numbat's salivary glands are large to provide enough saliva for this kind of eating. Another way that numbats find termites is by turning over fallen branches and sticks using their snout and front paws. A numbat that was studied in captivity ate between 10,000 and 20,000 termites per day. In the course of eating termites, ants and other insects sometimes also are consumed. Numbats do not chew their food, even though they have more teeth (between forty-eight and fifty-two of them) than any other marsupial.

THE DANGER OF INTRODUCING A FOREIGN SPECIES

Whenever an new animal is introduced into an environment, there can be unexpected consequences. The red fox was introduced when Europeans arrived in Australia. For numbats and several other Australian species, the introduction of this animal was disastrous. Numbats had not evolved ways to protect themselves against this new, non-native predator. As a result, foxes killed thousands of numbats and numbat populations substantially decreased. Only by starting programs to lessen the number of red foxes could the numbats be saved.

BEHAVIOR AND REPRODUCTION

The numbat is a solitary animal and is the only Australian mammal that is active only during the day (diurnal). During most of the year, numbats are active from mid-morning until late afternoon, when the temperatures are warmest. However, during the hottest part of the year they avoid activity around noon and prefer to forage in the early morning and late afternoon.

When numbats reproduce, they do not form pairs, so the female is left to raise her young alone. After only a fourteen-day pregnancy, the female gives birth to an average of four young, which she continues to carry without a pouch. Marsupial mammals like the numbat do not form a placenta when their young are in their mother's womb. Instead, they are born underdeveloped and spend time developing outside attached to their mother's milk teats. Unlike other marsupials, the numbat does not have a pouch. When the young are born, they are hairless and their eyes are still sealed shut. They crawl toward their mother's nipples, which are on her belly, and attach themselves there. They remain on the mother's belly and are carried with her for six to seven months while they grow hair and continue to develop. The young then spend several more months in the mother's nest. While in the nest, their eyes open and they begin to explore. By early the following year, numbat young venture out on their own.

NUMBATS AND PEOPLE

The numbat was known to central Australian aboriginal (native) people as "walpurti." At one time they were hunted for food. Aboriginal people would track individual numbats to their burrows and then dig them up. Today they have no known economic value, although scientists and ecotourists are interested in observing them. As many as two hundred numbats have been collected as museum specimens.

CONSERVATION STATUS

Numbats are a conservation success story. By 1985, so many numbats had disappeared that only two numbat populations remained. At that time they were considered Endangered and likely to become extinct. An effort to increase numbat populations was undertaken that involved the poison baiting of red foxes, a major predator of the numbat. Numbat populations were also moved into other habitats, and numbats that had been raised in captivity were introduced into the wild. These programs have been successful, because there are now nine wild numbat populations and two that live on fenced reserves. In 1994, numbats were upgraded from Endangered to a conservation status of Vulnerable. Although they are still at risk, they are unlikely to become extinct in the immediate future.

FOR MORE INFORMATION

Books:

Swan, Erin Pembrey, and Jose Gonzales. Meat-Eating Marsupials (Animals in Order). New York: Franklin Watts, 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.