Australia

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2

Animals

A large proportion of Australia’s native animal species exist nowhere else in the world. Of Australia’s animal species, it is estimated that 84 percent of mammals, 89 percent of reptiles, 93 percent of frogs, and 45 percent of birds are endemic. Some archaic species, such as the Queensland lungfish, have changed little since Paleozoic or Mesozoic times. Scientists estimate that 19 land mammals and 20 birds have become extinct (that is, not sighted in the wild for at least 50 years) since European settlement. The World Conservation Monitoring Centre classifies 63 mammals, 60 birds, 38 reptiles, and 47 amphibians as threatened.

One striking aspect of the native mammal life in Australia is the absence of representatives of most of the orders found on other continents. In contrast to other continents, Australia has a preponderance of marsupials (mammals that raise their young in a marsupium, or abdominal pouch), with some 144 original species (10 became extinct after 1788). Australia is also noted for its comparatively abundant presence of monotremes, which are egg-laying mammals. Only two types of monotremes native to Australia are known to survive. The platypus, a zoological curiosity, is a semiaquatic, furred mammal with an elongated snout resembling a duck bill; the legs of the adult male platypus are equipped with poisonous bony spurs for defense. The platypus is found in eastern and southern Australia, including Tasmania. The other monotreme is the spiny anteater, or echidna, which is found throughout Australia as well as New Guinea.

The best-known marsupials of Australia are the kangaroos, which include about 50 species. Kangaroos are herbivores. They dwell in many areas of the country, and some have become so accustomed to humans they can be considered tame. The large red or gray kangaroo may stand as high as 2 m (7 ft) and can leap up to 9 m (30 ft). The wallaby and kangaroo rat are smaller members of the kangaroo family. The phalangers are herbivorous marsupials that live in trees, including the ringtail possum. The koala, also a tree-dwelling marsupial, is found in the wild only in the eucalyptus forests of eastern Australia. Other well-known marsupials are the burrowing wombat, bandicoot, and pouched mouse. The carnivorous Tasmanian devil, principally a scavenger, is found only on the island of Tasmania.

Rodents, bats, and the dingo belong to a different order of mammals. Scientists believe they were the earliest significant nonnative species, arriving from the Asian mainland and the string of islands to the north of Australia thousands of years ago. While rodents and bats migrated on their own, the doglike dingo was perhaps the first species to be introduced by humans. It is believed that dingoes were introduced into Australia about 4,000 years ago by seafarers from Southeast Asia and the Indonesian islands.

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When Europeans settled in Australia, they brought many species of animals with them. Many of these originally domesticated animals have established large feral (wild) populations, including horses (locally known as brumbies), cattle, cats, camels, deer, dogs, donkeys, goats, pigs, rabbits, and water buffalo. These animals have spread throughout the country, most notably in the sparsely populated outback, causing serious ecological and economic damage. The most widespread damage has been caused by the European rabbit, which was brought to Australia in the mid-19th century mainly for sport. These rabbits quickly reached plague proportions on the continent, where they had no natural predators, and their total population reached as many as 500 million. The damage they cause includes soil erosion, the destruction of habitat for native species, and large agricultural losses. Rabbits, as well as foxes and feral cats, have been repeatedly targeted for massive national efforts in biological control and regional eradication programs.

Another introduced species, the South American cane toad, was imported in 1935 from Hawaii into Queensland’s sugarcane country in the hope of controlling beetles and other insect pests. However, it became a grotesquely successful pest in its own right. In the absence of serious predators, the toad has infested much of the state and is migrating into the northern tropics.

Australia’s indigenous amphibians are modest in number due to the prevailingly dry climate. However, some have developed ways to survive the harsh climate of the Australian outback. The burrowing bullfrog, for example, emerges from its underground home to feed and mate only during the brief, infrequent rains.

Australia contains a wide variety of reptile life. In fact, a majority of the land vertebrates are in this class. There are more than 500 species of lizards, including the gecko, skink, and the giant goanna. About 100 species of venomous snakes are found in Australia. The taipan of the far north, the death adder, the tiger snake of the south, the copperhead, and the black snake are the best known of the poisonous snakes. Australia also has two species of freshwater crocodiles. The larger of these, found in the estuaries and coastal swamps along the northern coast, attains lengths of 6 m (20 ft).

The waters surrounding Australia support a wide variety of fish and aquatic mammals. Several species of whales populate southern waters, and seals inhabit parts of the southern coast, the islands in Bass Strait, and Tasmania. Dugong, trepang (sea cucumber), trochus, and pearl shell are found in northern waters. Edible fish and shellfish are abundant, and the oyster, abalone, and crayfish of the warmer southern waters have been exploited commercially. Australian waters contain some 70 species of shark, several of which are dangerous to humans. The Queensland lungfish, sometimes called a living fossil, breathes with its single lung when low river levels render its gills ineffective. Australia has about 3,000 species of marine and freshwater fish. Introduced species, most conspicuously the European carp, threaten the survival of many native species.

Most insect types are represented in Australia, including flies, beetles, butterflies, bees, mosquitoes, and ants. Several of the 260 or so types of mosquitoes are responsible for the transmission of disease to animals and humans in the country’s tropical and temperate regions. The giant termites of northern Australia build huge, hill-like nests up to 6 m (20 ft) in height. Australia has earthworms in abundance, including the giant earthworms of Victoria, which range from 0.9 to 3.7 m (3 to 12 ft) in length, reportedly the longest in the world.

Australia is the home of 649 known species of birds, ranging from archaic types, such as the giant, flightless emu and cassowary, to highly developed species. The fan-tailed lyrebird has great powers of mimicry. The male bowerbirds build intricate and decorative playgrounds to attract females. The largest species of kookaburra has a raucous call for which it is nicknamed the “laughing jackass.” Many varieties of cockatoos and parrots are found; the budgerigar is a favorite of bird fanciers. The white cockatoo, a clever mimic, is more common than the black cockatoo. Black swans, spoonbills, herons, and ducks frequent inland waters. Smaller birds include wrens, finches, titmice, larks, and swallows. Gulls, terns, gannets, mutton birds, albatrosses, and penguins are the most common seabirds. The mutton bird, found mainly on the islands of Bass Strait, is valued for its edible flesh.

G

Soils

All major soil types are present to varying degrees throughout the continent. The arid and semiarid regions provide the most extensive group of soils. These soils are mainly suitable only for light livestock grazing. Most useful for this purpose are some of the desert loam areas of South Australia and New South Wales and the arid red earths of south central Queensland, northern New South Wales, and northern South Australia. The vast areas of stony desert, sand plain, and sand hills that cover the bulk of central Australia are of very little or no use for livestock. Soils of the semiarid zones include heavy-textured gray and brown soils in northwestern Victoria that support productive farming of grains and other crops. Soils of the humid and seasonally humid zones occupy a much smaller portion of the land area, including the Great Dividing Range, east central Victoria, and Tasmania.

Only 6.4 percent of Australia’s total land area is arable. Because of extensive leaching of minerals, especially in areas of higher rainfall, most Australian soils are not particularly fertile. Phosphate and nitrogen are widely lacking, and large areas lack trace elements necessary for crop nutrition. To address these deficiencies, phosphate additives have been used extensively as soil fertilizers for many years, and leguminous plants such as subterranean clover are grown to add nitrogen to the soil. In addition, large areas of marginal land have been made more productive by the addition of trace elements, such as zinc, copper, and manganese. However, water runoff from fertilized soils has been linked to periodic outbreaks of toxic blue-green algal blooms in the Murray-Darling Basin, and the growing of subterranean clover has led to soil acidification through the leaching of nitrates.

Soil erosion and desertification due to poor farming practices have occurred in many areas, especially on overgrazed and logged land. Wind erosion in the semiarid pastoral and agricultural regions and water erosion in the wetter, deforested southeastern regions also pose major problems. Salinization and alkalization of soil is another common problem because Australia has few large, permanent rivers for irrigation. A large amount of irrigation water comes from wells that tap underground artesian basins, most of which supply somewhat saline water of poor to marginal quality.

A nationwide community-based movement called Landcare won significant government support, at federal and state levels, to address these problems, and the 1990s was officially declared the Decade of Landcare. The Landcare movement has harnessed local skills to tackle urgent problems such as soil erosion and salinization. Important gains include increased attention to the need for innovative, adaptive farming practices. In 2001 there were more than 4,500 community Landcare groups, all federally assisted under National Landcare Program funding as part of the Natural Heritage Trust.

H

Environmental Issues

Australia’s long global isolation and unique patterns of biological evolution were disrupted by the comparatively late and sudden settlement of ambitious, technologically advanced Europeans. From the start, the settlers’ optimistic aspirations collided with the continent’s environmental constraints on development, especially its arid or semiarid climatic conditions, low levels of soil fertility, chronic water shortages, and vulnerable native animal and plant species. The settlers, deluded in part by the sheer immensity of Australian space and low population densities, strove to adapt the land to their own purposes. Although there were important dissenting voices, even in colonial times, popular attitudes and government policies largely favored rapid development until the latter half of the 20th century. Beginning in the 1960s, vigorous environmental activism targeted high-profile and controversial issues, such as the damming of Tasmania’s Lake Pedder. This activism successfully stirred public awareness by articulating the environmental impacts of development. Attitudes gradually began to change, in response to grassroots environmentalism as well as in recognition of a much-depleted resource base.

Two major environmental goals became increasingly evident: the sustainable development of natural resources and the conservation of relatively undisturbed areas. At the regional and local levels, governments stepped up their policing of pollution and other abuses of the environment, while activists clashed periodically with developers over threats to forests and woodlands, native wildlife, water bodies, and natural recreational areas. Robust monitoring by environmentalists eventually produced more sensitive approaches to development planning in both urban and rural areas, including the standard incorporation of environmental-impact statements.

Since the 1990s the federal government has made efforts to better coordinate environmental policies at the national and regional levels. Under the commonwealth constitution, individual states retain control of environmental management within their own borders. Many natural regions span state borders, however, and they require coordination between federal and state authorities to be effectively managed. One prominent example of coordination between federal and state authorities on environmental issues is the management of the Murray-Darling Basin. This gigantic river basin in southeastern Australia extends over three-quarters of New South Wales, more than half of Victoria, significant portions of Queensland and South Australia, and the entire Australian Capital Territory. Due to past irrigation practices, land and water salinity now threaten the basin, which is the heartland of agricultural productivity in Australia. Legislation introduced in 1993 put the basin under the joint supervision of the federal and state governments to create an integrated catchment management program. Local communities have also been included in the decision-making process. Community concerns about increasing soil salinity and water shortages in certain hard-pressed rivers were important factors in the decision to cap water diversions in the basin beginning in the mid-1990s.

In 1999 comprehensive new environmental legislation, the Commonwealth Environmental Protection and Biodiversity Conservation Act, extended federal rights and responsibilities for environmental matters of national significance. The legislation reflected rising concerns over the need to protect the rich biodiversity of Australia. It strengthened the federal role in the National Reserve System program, which aims to establish a network of protected areas that includes all types of ecosystems across the country. The Natural Heritage Trust was set up in 1997 specifically to fund the program. The system protects about 6.7 percent of Australia’s land area, including about 16 percent of the country’s forests. In addition to terrestrial parks and reserves, the system includes a number of marine and estuarine reserves, such as the massive Great Barrier Reef Marine Park. The system encompasses 14 World Heritage Sites, which are places designated for their outstanding universal value by the World Heritage Committee of the United Nations Educational, Scientific and Cultural Organization (UNESCO), and a number of biosphere reserves, which are designated under UNESCO’s Man and the Biosphere Program. The National Reserve System also includes a number of Indigenous Protected Areas, which are established on a voluntary basis on lands held by Aboriginal and Torres Strait Islander people. This system is supplemented by the Australian National Estate, which includes more than 2,000 natural places that are considered significant components of the country’s environmental or cultural heritage.

Despite the growing number of protected areas, some of the most treasured areas in Australia continue to be environmentally threatened. Overuse by tourists and divers and increased industrial shipping in nearby waters threatens the health of the Great Barrier Reef. The lush, old-growth tropical forests of northern Queensland are coveted by the timber industry and tourist developments. These issues continue to be the focus of environmental activism in Australia. Environmental agencies, some of which are government funded, work to coordinate management of the coastal rain forests and reefs of northeastern Australia for multiple uses, including tourism, recreation, and conservation.

Although many of the environmental issues facing Australia are shared by other industrialized nations, certain aspects are uniquely Australian. For example, Australia has one of the lowest overall population densities of any country, but its per capita consumption levels and waste production are among the highest in the world. On a per capita basis, Australia is a leading contributor to the production of greenhouse gases, such as carbon dioxide, that contribute to atmospheric pollution and global warming.

Australia has ratified some international agreements to protect the environment, including arrangements to preserve Antarctica’s pristine state. Regionally, Australia cooperates with other South Pacific nations in the protection of the marine environment. Agreements to protect migratory birds have been made with Japan and China.

III

Population

Australia is the most sparsely populated of the inhabited continents. The estimated total population in 2007 was 20,434,176, giving the country an overall population density of 3 persons per sq km (7 per sq mi). Australia’s population grew at a relatively modest rate of about 1.3 percent annually from 1996 to 2001.

The country is heavily urbanized. Some 93 percent of the population lives in cities, about two-thirds in cities with 100,000 or more residents. The most rapidly growing areas are the coastal zones near and between the mainland capitals in the east, southeast, and southwest. In fact, four out of every five Australians live on the densely settled coastal plains that make up only about 3 percent of the country’s land area. The fastest-growing region is southeastern Queensland.

A

Political Divisions

The Commonwealth of Australia comprises six states and two territories. The states and their capitals are New South Wales (Sydney), Victoria (Melbourne), Queensland (Brisbane), South Australia (Adelaide), Western Australia (Perth), and Tasmania (Hobart). The territories and capitals are the Australian Capital Territory (site of the national capital, Canberra) and the Northern Territory (Darwin).

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