Geographically and genetically isolated, Tasmania is known for its unique flora and fauna.
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Tasmania has extremely diverse vegetation, from the heavily grazed grassland of the dry Midlands to the tall evergreen eucalypt forest, alpine heathlands and large areas of cool temperate rainforests and moorlands in the rest of the state. Many flora species are unique to Tasmania, and some are related to species in South America and New Zealand through ancestors which grew on the super continent of Gondwana, 50 million years ago.
Tasmania is also home to some of the tallest and oldest trees of the world. For example, some individual Huon pines are believed to be more than 2,000 years old, and a stand of male Huon pines at Mount Read which has maintained itself by vegetative reproduction is estimated to be more than 10,000 years old.[2]
The tallest trees in Australia, more than 90 metres (300 ft) tall, are Eucalyptus regnans found in the Styx Valley. As these are still growing, they may surpass the tallest tree ever measured in the country, a mountain ash growing at Thorpdale, Victoria that measured more than 112 metres (367 ft) before it was felled in 1884.[3] Tasmania hosts endemic plant genera as well as plant genera of restricted distribution; an example of such a genus is Archeria.
The island of Tasmania was home to the Thylacine, a marsupial which resembled a wild dog. Known colloquially as the Tasmanian Tiger for the distinctive striping across its back, it became extinct in mainland Australia much earlier because of competition by the dingo, introduced in prehistoric times. Owing to persecution by farmers, government-funded bounty hunters and, in the final years, collectors for overseas museums, it appears to have been exterminated in Tasmania.
The Thylacine was the largest known carnivorous marsupial of modern times. The Thylacine was one of only two marsupials to have a pouch in both sexes (the other is the Water Opossum). The male Thylacine had a pouch that acted as a protective sheath, protecting the male's external reproductive organs while running through thick brush. The last known animal died in captivity in 1936. Many alleged sightings have since been recorded, none of them confirmed. The mature Thylacine ranged from 100 to 130 cm (39 to 51 in) long, plus a tail of around 50 to 65 cm (20 to 26 in).[4] The largest measured specimen was 290 cm (9.5 ft) from nose to tail. Adults stood about 60 cm (24 in) at the shoulder and weighed 20 to 30 kg (40 to 70 lb).[4] There was slight sexual dimorphism with the males being larger than females on average.[5]
The Tasmanian Devil is a carnivorous marsupial found exclusively on the island of Tasmania. The size of a small dog but stocky and muscular, the Tasmanian Devil is characterised by black fur with white patches. It has a loud and disturbing screech-like growl, possesses a vicious temperament and is predominantly a scavenger. The Devil survived European settlement and was considered widespread and common throughout Tasmania until recently. As with a lot of wildlife, fast vehicles on roads are a problem for Tasmanian Devils, which are often killed while feeding on other road-killed animals such as wallabies. They eat everything including bone.
As of 2005, the Tasmanian Devil population has been reduced by up to 80% in parts of Tasmania by the devil facial tumour disease, which is gradually spreading throughout the island. It is believed the majority starved when the tumours spread to their mouths, and that the tumours are spread by fighting between devils over carcasses they feed on – typically, fighting devils will bite one another's faces.
There is no known cure for the disease, and intensive research is underway to determine its cause. There is also a captive breeding program being undertaken by the Tasmanian government to establish a disease-free, genetically diverse population of Tasmanian Devils outside Tasmania. This has been relatively successful so far.
Many birds of the Australian mainland and surrounding oceans are also found in Tasmania. Tasmania has 12 endemic bird species:
The endemic Tasmanian Emu was exterminated in the mid-19th century. The Tasmanian Wedge-tailed Eagle is a threatened endemic subspecies.
Tasmania is home to 11 species of frog. Three of these are found only in Tasmania, the Tasmanian Tree Frog (Litoria burrowsae), the Tasmanian Froglet (Crinia tasmaniensis) and the recently discovered Moss Froglet (Bryobatrachus nimbus). Of the 11 species that inhabit Tasmania all are native to Australia. Tasmania is home to the largest breeding population of Growling Grass Frogs (Litoria raniformis), a vulnerable species, which has declined over much of its range.
On 20 June 2001, Tasmania formed a fox task force, now the Fox Eradication Branch, to eliminate the European red fox. Officials planned to spend up to A$50 million on an eradication campaign, which has since been reduced. No foxes have been captured, poisoned or photographed with certainty in the Island state, although four carcasses have been recovered. Of these, one was claimed to be shot, and the other 3 presumed road-kills. The lack of an abundance of foxes, through low population densities, and fox-poisoning campaigns, has resulted in an abundance of denial of fox presence by the Tasmanian community. Established foxes in Tasmania could devastate native mammals, livestock, ground-nesting birds and native rodents. Experts estimate there are fewer than 30 million foxes on mainland Australia, having been introduced by European settlers.[6]
Since white settlement, about 28 native mammal species or subspecies have become extinct from the Australian mainland, the worst rate of continental extinction in the world. Red Foxes are known to be a significant contributing factor to this. Mainland extinctions or near-extinctions include the Eastern Barred Bandicoot, Eastern Quoll, and Tasmanian Pademelon (Thylogale billardierii); all still common in Tasmania. A member of the upper house, the Legislative Council member for Windermere Ivan Dean MLC has been publicly critical of the fox evidence used to obtain funding for a taxpayer funded Fox Eradication Branch of the Tasmanian D.P.I.P.W.E. Former Tasmanian Police Commander, Mr Dean, led a Police investigation into the alleged importation and release of foxes into Tasmania. The investigation did not uncover any evidence of illegal importation. He then raised the Tasmanian Fox issue in the Tasmanian Parliament on 17 April 2007.[7]
In addition to the 4 carcasses, over 40 independently tested fox-DNA-confirmed scats have been located across Tasmania. Through Government review, Foxes are now confirmed to be in Tasmania.[8] Certain prominent Tasmanians including Dr David Obendorf have been calling for a Federal Police investigation into allegations that evidence has been planted and this is all part of an elaborate hoax to receive funding from the Commonwealth.[9]
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