SPINY BANDICOOTS: Peroryctidae

PHYSICAL CHARACTERISTICS

Peroryctidae are spiny bandicoots. They look like a cross between a rabbit and a rat. In many ways they are similar to the bandicoots in the Peramelidae family. Spiny bandicoots range in size from about 6.5 to 22 inches (17.5 to 56 centimeters), not including the tail. They vary in weight from 14 ounces to 10 pounds (0.4 to 4.7 kilograms). The giant bandicoot of southeastern New Guinea is the largest species. The mouse bandicoot is the smallest.

Spiny bandicoots have rough, spiky fur that is usually blackish or brown on the back and white or tan on the belly. Most species are a solid color, but the striped bandicoot has darker stripes on its rump and around its eyes. Like the true bandicoots, spiny bandicoots have claws that are adapted to digging for food. Their front feet have five toes. The middle three toes have strong claws. Toes one and five are either small or absent. On the hind feet, the bones of the second and third toes are joined, but each toe has a separate claw. The hind legs are longer than the front legs and are strong and well developed for hopping and leaping. They are also able to move with a running gait.

Spiny bandicoots differ from true bandicoots mainly in the shape of their skulls, the habitats they prefer, and the roughness of their fur. Recent studies show that they also are genetically different from true bandicoots.

GEOGRAPHIC RANGE

Spiny bandicoots live mainly on the island of New Guinea and a few small neighboring islands. One species is found in Australia only on the northernmost tip of Queensland, the part of Australia closest to New Guinea.

HABITAT

Spiny bandicoots prefer damp, humid habitats. They live in tropical rainforests and mountain rainforests at elevations from zero to 14,800 feet (zero to 4,500 meters). Species living in the same area tend to live at different elevations.

DIET

Like all bandicoots, spiny bandicoots are omnivores, meaning they eat both animals and plants. Most of their diet consists of insects, insect larvae, earthworms, spiders, centipedes, bulbs, seeds, and fallen fruit. Spiny bandicoots appear to eat more vegetable material, especially fruit, than true bandicoots. This may be because fruit is more available in the damp habitats they prefer than in the dry habitats preferred by true bandicoots. They either lick their food off the ground or dig for it with their strong claws. They can dig holes up to 5 inches (13 centimeters) deep and scoop out the food with their long tongues.

BEHAVIOR AND REPRODUCTION

Spiny bandicoots are nocturnal, feeding during the night and resting during the day in nests of leaves, hollow logs, or shallow burrows. They live alone, coming together only briefly to mate. They are territorial animals, protecting an area against other members of their species and becoming aggressive if their area is invaded.

THE TINIEST BANDICOOT

The mouse bandicoot measures only 6 inches (15 centimeters) long. It is extremely difficult to observe, and was not discovered until 1932. It lives in moss forests at altitudes of 6,300 to 8,200 feet (1,900 to 2,500 meters), and is active only at night. By 1977 only four specimens of this species had been collected for study.

Little is known about spiny bandicoots. They are difficult to observe, because they live in remote or mountainous areas and are active only at night. Bandicoots are marsupial mammals. Most marsupials have what is called a yolk-sac placenta. A placenta is an organ that grows in the mother's uterus (womb). In eutherian (yoo-THEER-ee-an) mammals, such as dogs, cows, and humans, the placenta allows the developing offspring share the mother's food and oxygen. In animals with a yolk-sac placenta, there is no sharing of the mother's food and oxygen.

Bandicoots differ from other marsupials, because they have a second placenta in addition to the yolk-sac placenta. This placenta resembles the placenta of eutherian mammals, but does not function as well, because it does not attach as closely to the wall of the mother's uterus. As a result, spiny bandicoots have short pregnancies, and the young are born nearly helpless. They drag themselves into their mother's pouch where they attach to her teats, or nipples and are carried until they have matured. Spiny bandicoots normally have only one or two young at a time, but little is known about how long they are carried in their mother's pouch, when they become old enough to reproduce, or how long they live in the wild.

SPINY BANDICOOTS AND PEOPLE

In New Guinea, spiny bandicoots are hunted and are an important food source for native peoples. Otherwise, these animals are of interest mainly to scientists and conservationists.

CONSERVATION STATUS

Very little is known about the size of spiny bandicoot populations in the wild. In fact, so little is know about them that they are not given a conservation rating, although they probably are under pressure from human activities such as logging.

RUFOUS SPINY BANDICOOT (Echymipera rufescens): SPECIES ACCOUNT

Physical characteristics: Rufous spiny bandicoots have a total head and body length of about 12 to 16 inches (30 to 41 centimeters) and weigh between 1.1 and 4.4 pounds (0.5 to 2.0 kilograms). The short black tail is almost hairless. The fur on their back is coarse, spiky, and reddish brown. The fur on their belly is white. The rufous spiny bandicoot sometimes is called the long-nosed echymipera, the spiny bandicoot, or the rufescent bandicoot.

Geographic range: The rufous spiny bandicoot is the only member of the Peroryctidae family that lives in Australia. There it lives only on the Cape York Peninsula of Queensland. This animal also lives in western and southeastern New Guinea and the neighboring islands of Kei and Aru.

Habitat: Rufous spiny bandicoots prefer lowland tropical rainforests below an elevation of 3,900 feet (1,200 meters). They occasionally are can be found in open costal woodlands or disturbed grasslands.

Diet: Rufous spiny bandicoots are omnivores, meaning they can eat both plants and animals, but their preferred food is insects. They feed on the ground, digging out insects with their claws and lapping them up with long, thin tongues.

Behavior and reproduction: This bandicoot lives and feeds on the ground and is strictly nocturnal. It digs shallow burrows to rest in during the day. Rufous spiny bandicoots live alone and appear to be territorial.

Very little is known about this animal's reproductive cycle. Some scientists believe that this species breeds year round in New Guinea and seasonally in Australia, but not enough animals have been studied to form firm conclusions. Litters usually consist of from one to three young that are carried in the mother's pouch until they mature.

Rufous spiny bandicoots and people: Native peoples of New Guinea hunt these bandicoots for food.

Conservation status: The rufous spiny bandicoot appears to be common to abundant within its very limited range, especially in Australia. However, the small number of places in which this species is found has become cause for concern among conservationists. ∎

FOR MORE INFORMATION

Books:

Finney, Tim F. Mammals of New Guinea, 2nd ed. Ithaca, NY: Cornell University Press, 1995.

Menkhorst, Frank. A Field Guide to the Mammals of Australia, 2nd ed. Oxford, U.K.: Oxford University Press, 2001.

Nowak, Ronald M. Walker's Mammals of the World. Baltimore: Johns Hopkins University Press, 1995. http://www.press.jhu.edu/books/walkers_mammals_of_the_world/marsupialia/marsupialia.peramelidae.echymipera.html (accessed on June 30, 2004).

Web sites:

University of Michigan Museum of Zoology. "Family Peroryctidae."Animal Diversity Webhttp://animaldiversity.ummz.umich.edu (accessed on June 30, 2004).