The Top End of northern Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 is the second northernmost point on the continent. It covers a rather vaguely-defined area of perhaps 400,000 square kilometres behind the northern coast from the Northern Territory

Northern Territory

The Northern Territory is a federal territory of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions...

 capital of Darwin

Darwin, Northern Territory

Darwin is the capital city of the Northern Territory, Australia. Situated on the Timor Sea, Darwin has a population of 127,500, making it by far the largest and most populated city in the sparsely populated Northern Territory, but the least populous of all Australia's capital cities...

 across to Arnhem Land

Arnhem Land

The Arnhem Land Region is one of the five regions of the Northern Territory of Australia. It is located in the north-eastern corner of the territory and is around 500 km from the territory capital Darwin. The region has an area of 97,000 km² which also covers the area of Kakadu National...

 with the Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

 on the west, the Arafura Sea

Arafura Sea

The Arafura Sea lies west of the Pacific Ocean overlying the continental shelf between Australia and New Guinea.-Geography:The Arafura Sea is bordered by Torres Strait and through that the Coral Sea to the east, the Gulf of Carpentaria to the south, the Timor Sea to the west and the Banda and Ceram...

 to the north, and the Gulf of Carpentaria

Gulf of Carpentaria

The Gulf of Carpentaria is a large, shallow sea enclosed on three sides by northern Australia and bounded on the north by the Arafura Sea...

 to the east, and with the almost waterless semi-arid interior of Australia to the south, beyond the huge Kakadu National Park

Kakadu National Park

Kakadu National Park is in the Northern Territory of Australia, 171 km southeast of Darwin.Kakadu National Park is located within the Alligator Rivers Region of the Northern Territory of Australia. It covers an area of , extending nearly 200 kilometres from north to south and over 100 kilometres...

.

The Top End, though less frequently visited and less well-known overseas than the arid southern part of the Northern Territory

Northern Territory

The Northern Territory is a federal territory of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions...

, referred to by Australians as the Red Centre and the largest town of which is Alice Springs, contains the Territory's other major towns, Darwin

Darwin, Northern Territory

Darwin is the capital city of the Northern Territory, Australia. Situated on the Timor Sea, Darwin has a population of 127,500, making it by far the largest and most populated city in the sparsely populated Northern Territory, but the least populous of all Australia's capital cities...

, Katherine

Katherine, Northern Territory

Katherine is a town situated southeast of Darwin in the "Top End" of Australia in the Northern Territory. It is the fourth largest settlement in the Territory after the capital Darwin, Palmerston and Alice Springs...

 and Palmerston

Palmerston, Northern Territory

Palmerston is a planned satellite city of Darwin, the capital and largest city in Australia's Northern Territory. Palmerston is situated near Darwin Harbour and has an urban population of 23,614 on the 2006 Census night and making it the second largest city in the territory...

.

The landscape is relatively flat with river floodplains and grasslands with eucalyptus

Eucalyptus

Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...

 trees along with rocky areas and patches of rainforest, and in western Arnhem Land a high rugged sandstone plateau cut through with gorges, much of which is in Kakadu National Park. The rivers that form the wetlands include the South and East Alligator Rivers

Alligator Rivers

The Alligator Rivers is the name of a region in the Arnhem Land region of the Northern Territory of Australia, containing three rivers the East, West and South Alligator River...

, Mary River

Mary River (Northern Territory)

The Mary River flows in the Northern Territory of Australia and is a site of the Mary River National Park. Its lower reaches form part of the Adelaide and Mary River Floodplains Important Bird Area.-External links:**...

, and the Glyde River. The climate is tropical monsoon with a wet and dry season, bringing the highest rainfall in northern Australia (over 1200mm per year). Temperatures do not fluctuate widely throughout the year.

There are a number of islands off the Top End coast including the Tiwi Islands

Tiwi Islands

The Tiwi Islands are part of Australia's Northern Territory, north of Darwin where the Arafura Sea joins the Timor Sea. They comprise Melville Island and Bathurst Island, with a combined area of ....

 (Bathurst Island and Melville Island), and Groote Eylandt

Groote Eylandt

Groote Eylandt is the largest island in the Gulf of Carpentaria in northeastern Australia. It is the homeland of, and is owned by, the Anindilyakwa people who speak the isolated Anindilyakwa language)....

 as well as many smaller ones.

Flora

Most savanna

Savanna

A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...

 in Australia is used for grazing livestock, but in this far north, vast areas of grassland are in their original state and dotted with Darwin stringybark and Darwin woollybutt

Eucalyptus miniata

The Darwin woollybutt is a eucalypt which is native to Australia's Top End, found from Cape York in north Queensland across through to the Northern Territory into the Kimberley Region of northern Western Australia. It is a medium-sized tree which can reach 15–25 m in height. The bark is soft and...

  eucalyptus trees; these grasslands are a unique and highly important ecoregion. The sandstone plateau area of the ecoregion is a particularly rich centre of biodiversity supporting a unique heathland flora. Much of the Top End is within the Arnhem Land tropical savanna ecoregion

Ecoregion

An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

, which to the south merges into the semi-arid mulga

Mulga

Acacia aneura, commonly known as Mulga or True Mulga, is a shrub or small tree native to arid outback Australia of areas such as the Western Australian Mulga shrublands.-Description:...

 scrubland, mallee

Mallee Woodlands and Shrublands

Mallee Woodlands and Shrublands is a Major Vegetation Group which occurs in semi-arid areas of southern Australia. The vegetation is dominated by mallee eucalypts which are rarely over 6 metres high...

, and sand dunes of the centre (see Carpentaria

Gulf Country

The Gulf Country is the name given to the region of woodland and savanna grassland surrounding the Gulf of Carpentaria in north western Queensland and eastern Northern Territory on the north coast of Australia...

, Kimberly, and Ord Victoria Plain

Ord Victoria Plain

Ord Victoria Plain is an Interim Biogeographic Regionalisation for Australia region in Western Australia. and Northern Territory.-Location and description:...

). The transition is gradual, and the demarcation line that divides the Top End from the centre is arbitrary.

Fauna

This area is home to unique wildlife. The rivers and estuaries are home to large populations of both saltwater

Saltwater Crocodile

The saltwater crocodile, also known as estuarine or Indo-Pacific crocodile, is the largest of all living reptiles...

 and freshwater crocodile

Freshwater Crocodile

The freshwater crocodile , also known as the Australian freshwater crocodile, Johnston's crocodile or colloquially as freshie, is a species of reptile endemic to the northern regions of Australia...

s, as well as bull shark

Bull shark

The bull shark, Carcharhinus leucas, also known as Zambezi shark or unofficially known as Zambi in Africa and Nicaragua shark in Nicaragua, is a shark common worldwide in warm, shallow waters along coasts and in rivers...

s, sawfish

Sawfish

Sawfish, also known as the Carpenter Shark, are a family of rays, characterized by a long, toothy nose extension snout. Several species can grow to approximately . The family as a whole is largely unknown and little studied...

, and dugong

Dugong

The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow , was hunted to extinction in the 18th century...

s. The wetlands are a rich habitat vital to bird migration and home to large populations of birds, including the world's largest breeding colony of Magpie geese, as well as large numbers of rodents and snakes. Endemic species of the Top End include the Woodward's walleroo

Woodward's Wallaroo

Woodward's Wallaroo , also known as the Black Wallaroo and Bernard's Wallaroo, is a species of macropod restricted to a small, mountainous area in Arnhem Land, Northern Territory, between South Alligator River and Nabarlek...

, Oenpelli python

Morelia oenpelliensis

Morelia oenpelliensis is a very large python species found in Australia. It is commonly known as the Oenpelli python. No subspecies are currently recognized.-Description:...

, chestnut-quilled rock-pigeon

Chestnut-quilled Rock-Pigeon

The Chestnut-quilled Rock Pigeon is a species of bird in the Columbidae family.It is endemic to Australia....

, Arnhem Land rock rat, and several species of skink

Skink

Skinks are lizards belonging to the family Scincidae. Together with several other lizard families, including Lacertidae , they comprise the superfamily or infraorder Scincomorpha...

s. Other reptiles include frill-necked lizards

Frill-necked Lizard

The frill-necked lizard , also known as the frilled lizard or frilled dragon, is found mainly in northern Australia and southern New Guinea. Its name comes from the large frill around its neck, which usually stays folded against the lizard's body. It is largely arboreal, spending the majority of...

 and large monitor lizard

Monitor lizard

Monitor lizards are usually large reptiles, although some can be as small as in length. They have long necks, powerful tails and claws, and well-developed limbs. Most species are terrestrial, but arboreal and semiaquatic monitors are also known...

s (known locally as goanna

Goanna

Goanna is the name used to refer to any number of Australian monitor lizards of the genus Varanus, as well as to certain species from Southeast Asia.There are around 30 species of goanna, 25 of which are found in Australia...

s). Snakes include the olive python, death adder

Death adder

Death adder may refer to:In herpetology:* All members of the genus Acanthophis, a group of highly venomous elapids found in Australia and New Guinea* Agkistrodon contortrix, a.k.a...

, mulga

Mulga

Acacia aneura, commonly known as Mulga or True Mulga, is a shrub or small tree native to arid outback Australia of areas such as the Western Australian Mulga shrublands.-Description:...

, water python (Liasis fuscus

Liasis fuscus

Liasis fuscus is a non-venomous python species found in Australia and Papua New Guinea. No subspecies are currently recognized.-Description:...

), and various others. The plateau is home to many of these endemics, especially invertebrates, fish, and frogs, including, for example, hundreds of species of ants. The offshore islands are home to unique subspecies of some of this wildlife.

Threats and preservation

The landscape is well preserved and most of the area is traditionally managed by Aboriginal land trusts

Aboriginal Land Rights Act 1976

In Australian history, the Aboriginal Land Rights Act established the basis upon which Aboriginal people in the Northern Territory could claim rights to land based on traditional occupation. The Act was strongly based on the recommendations of Justice Woodward, who chaired the Aboriginal Land...

, including Kakadu, which is Australia's largest national park and a World Heritage Site

World Heritage Site

A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

. Although some populations have declined, there have been no major extinctions of wildlife in this area. Darwin, though, is a growing city and a base for agriculture, tourism and mining, all of which threaten habitats. Introduced plants and animals, such as the water buffalo

Water buffalo

The water buffalo is a domesticated bovid widely kept in Asia, Europe and South America.Water buffalo can also refer to:*Wild water buffalo , the wild ancestor of the domestic water buffalo...

, are also changing natural habitats, and there has been criticism of the way the local population has changed the fire regime

Fire regime

A fire regime is the pattern, frequency and intensity of the bushfires and wildfires that prevails in an area. It is an integral part of fire ecology, and renewal for certain types of ecosystems. If fires are too frequent, plants may be killed before they have matured, or before they have set...

s used to control the bush foliage, in which large areas are burnt each year and allowed to renew.