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The cool, wet rain forests of this ecoregion stretches throughout western Tasmania. In the more elevated areas, snow is common during the winter months. The forest floor normally is covered with a thick layer of decaying matter and mosses. Green moss extends up the trunks of trees such as summit cedars and pencil pines. Beech trees also grow here, their leaves turning color each fall from green to yellow to bright red. In areas without fires, the Huon pine and King Billy pine are dominant. Huon pines are extremely slow-growing but may reach ages of 1,500 years and heights of 130 feet (40 m). They are capable of reproducing by seed or from sprouts on fallen trees. One of these pines or a small number of them can give rise to a stand of genetically identical trees, such as the all-male stand that has existed for 10,000 years on Mt. Read.
While politically part of Australia, Tasmania has been separated from the mainland for the last 8,000 to 12,000 years, as sea levels rose to create the Bass Strait between the two. The vegetation found here is actually more similar to temperate forests on New Zealand than to any vegetation found on the Australian mainland. Many of the plants are ancient remnants from when the continents formed a single land mass called Gondwana, and there is low diversity among the vascular plants. These forests are unusual because vines, orchids, and bromeliads are rare, yet mosses and lichens are abundant. While the vegetation may be similar to that of New Zealand, Tasmania shares most of its mammal species with Australia, though a few are endemic to Tasmania.
This ecoregion contains the only breeding grounds for the endangered orange-bellied parrot. Nesting in salt marsh and dune habitats along the coast, the birds make the arduous trip across the Bass Strait each year to spend the summer on the Australian mainland. Found only on Tasmania, colorful green rosellas breed here, while Tasmanian thornbills and scrubwrens fly through the dense forest. The most famous Tasmanian marsupial is the Tasmanian devil, a squatty, dog-like animal. Found throughout Tasmania, the devil once lived on the Australian mainland but died out before the arrival of Europeans. This nocturnal carnivore eats mostly carrion and can often be heard noisily fighting over food. The fierce, cat-sized spotted-tail quoll also comes out at night to hunt. Found only in moist forests, the tiny eastern pygmy possum must enter torpor, a physiological state similar to hibernation, to survive the cold Tasmanian winters. The duck-billed platypus uses its webbed feet and wide, flat tail to swiftly navigate coastal streams. A most unusual mammal, a platypus mother lays eggs but still nurses her young from milk ducts in her abdomen. The primitive Hickman’s Mountain shrimp belongs to an endemic group of invertebrates that existed 200 million years ago. Strangely, this shrimp is threatened by flooding. While it was once aquatic and lived in an ancient lake system, it became more terrestrial as the lakes dried up. It lives in isolated crayfish burrows and is also threatened by fires.
The largest area of cool temperate rain forest is in northwestern Tasmania. A large portion of this area is protected as national parkland within the Tasmanian Wilderness World Heritage Site. Logging, mining, off-road-vehicle recreation, and invasive plants are all threats. Fire poses a major threat to Huon and King William pines, possibly contributing to localized extinctions of these plants. Many mammals that are rare on the Australian mainland are more common here, partly because of the large protected areas found here and partly because there are fewer introduced predators in Tasmania. The fox and the dingo, for example, were never introduced to Tasmania as they were on the mainland. For more information on this ecoregion, go to the World Wildlife Fund Scientific Report. All text by World Wildlife Fund © 2001
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