Tasmanian Wolf: Thylacinidae

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TASMANIAN WOLF: Thylacinidae

PHYSICAL CHARACTERISTICS

Although Tasmanian wolves, sometimes called Tasmanian tigers, are extinct, or no longer living today, scientists have learned much about them from fossils and earlier written records. These wolves looked like dogs, and they walked on all four legs, although their legs were shorter than most dogs. They had a long narrow snout, ears that stood up, and a straight tail. Tasmanian wolves had short sandy-brown hair with a distinctive set of stripes that ran across their back. The stripes were dark brown and ran from the shoulders to the base of the tail.

Female Tasmanian wolves were smaller than males, with some males growing to twice the weight of females. While females may have averaged 33 pounds (15 kilograms), males could grow to be more than 60 pounds (27 kilograms). Tasmanian wolves had sharp teeth with four incisors in the top of their mouth and three in the bottom. This allowed them to tear their preferred food, meat.

Like all native Australian and Tasmanian mammals, Tasmanian wolves were marsupials. They lacked a placenta, an organ that grows in the mother's uterus and lets the mother and developing baby share food and oxygen. Because of this, they gave birth to young that were physically immature and unable to survive on their own. After a short pregnancy, the young were carried for several months in a pouch that opened under the mother's tail and faced backward. The young attached to milk teats, or nipples, in the pouch and fed until they grew large enough to survive on their own.

GEOGRAPHIC RANGE

When Tasmanian wolves were still alive, they were thought to have lived on the entire island of Tasmania. By the 1800s, Tasmanian wolves were rare in the southwest and western regions of the island, except in coastal areas. Scientists have learned this by reading the diaries of early settlers and examining the bounty payment records of people who lived during that time. Early settlers in Tasmania thought of Tasmanian wolves as pests to be eliminated, and bounty money was paid to hunters who killed them.

HABITAT

Tasmanian wolves lived in a great variety of habitats, although most often they were found in open areas. These included grassy woodlands, open forests, and coastal regions. They avoided dense forests and wetlands and liked to live in areas that Tasmanian devils, another animal in this order, live in today. The Tasmanian wolves hid in rock outcroppings and dense vegetation during the day and probably built dens there, but they would hunt at night in open grasslands.

DIET

Since Tasmanian wolves are no longer living today, no one knows for sure what they ate. When they were alive, people were more interested in classifying them and studying how they were related to other animals than in learning about how they lived or what they ate. Scientists can make some guesses about their diet, however, by comparing Tasmanian wolves to animals that live today.

Tasmanian wolves were carnivores, or meat eaters. It is believed that they ate many different kinds of animals including birds, small mammals, and even some larger mammals such as wombats, bandicoots, possums, and kangaroos, although it is likely that these larger animals were eaten less often. By looking at the size of their leg bones, scientists believe that Tasmanian wolves did not run very fast, and captured their prey by sneaking up on it or ambushing it rather than running it down.

BEHAVIOR AND REPRODUCTION

Not much is known about the behavior and reproduction of Tasmanian wolves. These animals were bred in captivity only once, although females with live young in their pouches were caught and kept in zoos. Scientists think that reproduction was timed so that young Tasmanian wolves left their mothers during the warmer months, as this was when food was more available, giving the young a better chance of survival. They believe that pregnancy lasted only one month. The poorly developed young then moved into the mother's pouch where they nursed until they were developed enough to survive on their own and eat solid food. Beyond this, little is known about their reproductive systems, how long the young would stay in their mother's pouch, or even how many young were in an average litter.

TASMANIAN WOLVES AND PEOPLE

People have had unfriendly relationships with Tasmanian wolves. Native peoples on the island of Tasmania and in Australia killed and ate Tasmanian wolves for food. It is thought that although many groups did use the Tasmanian wolves for food, some would build special shelters to worship the head and skin of the animal afterwards.

Once European settlers and farmers came to the region, hunting of the wolves increased dramatically. Sheep farmers were losing sheep and assumed that the Tasmanian wolves were responsible. It is likely that the wolves did kill some sheep, but wild dogs probably killed more sheep that the wolves. Even so, farmers and bounty hunters continued to hunt the Tasmanian wolves. By the early 1900s, most were gone, and by 1912 bounty hunting of Tasmanian wolves was halted. This was not early enough to save them from extinction. The last time a Tasmanian wolf was confirmed to exist in the wild was in 1930. Despite the official protection that began on July 14, 1936, the last Tasmanian wolf died that September.

FARMING AND WILD ANIMALS

When people begin to farm in areas that were once wild, they often interact with new animals. Farmers who raise sheep, cattle, or other livestock find that wild animals will feed on their flocks. This was probably true of the Tasmanian wolves, although most scientists believe that wild dogs were responsible for killing more sheep and cattle than Tasmanian wolves. Even so, farmers hunted Tasmanian wolves and hired bounty hunters to help them. This drove the Tasmanian wolves to extinction, despite the fact that they may not have been responsible for all the farmers' losses.

CONSERVATION STATUS

Tasmanian wolves are extinct. They were killed off mostly by farmers and bounty hunters during the 1800s. Tasmanian wolves were thought of as pests and killers of livestock, much the way the coyote was thought of during the settlement of the American West.

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.

Swan, Erin Pembrey, and Jose Gonzales. Meat-Eating Marsupials (Animals in Order). New York: Franklin Watts, 2002.

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 Tiger." http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/BHAN-53777B?open (accessed on June 30, 2004).