Alpine landscapes are rare in Australia. In Tasmania, most mountainous areas occur in the west of the state, making up around 3% of the state’s total landmass, and 11% of the Tasmanian Wilderness World Heritage Area.
The highlands of the Cradle Mountain-Lake St Clair National Park include some of the world’s most unspoiled alpine environments, and are home to plants and animals that are found nowhere else on earth.
The alpine environment
Alpine areas are challenging environments, characterised by freezing cold, thick snow and ice, rain and ferocious winds. In Tasmania, the scouring force of retreating glaciers at the end of the last ice age, between 10,000 and 12,000 years ago, created an environment dominated by dolerite and quartzite mountains, and shallow soil comprised primarily of peat—the compacted remains of rich, organic plant material.
While some resilient trees, such as snow gums, grow in sheltered sites near the tops of mountains, most alpine plants in Tasmania are shallow-rooted, low-growing and extremely hardy. Plant communities include moorlands of tussock grasses and sedges, alpine herb fields, mosses and lichens and communities of small, dense shrubs growing up to two metres tall.
Some of the most remarkable of Tasmania’s alpine plants are the cushion plants. These plants, many of which are endemic to Tasmania, grow in a dense, rounded form, which provides protection from the elements. On some peat-rich alpine plateaus, cushion plants grow in large communities that cover the ground with a blanket of boulder-like green mounds.
Native conifers are also well adapted to alpine environments. These ancient plants have evolved to survive in extreme cold, and their flexible branches enable them to withstand heavy snow. Endemic Tasmanian conifers include the prostrate creeping pine (also known as strawberry pine), which grows in alpine heathlands, and the sub-alpine King Billy pine, pencil pine and celery top pine.
Animals of the Tasmanian alps
Some of the most fascinating inhabitants of alpine areas are also some of the smallest. Several species of colourful alpine moths thrive here, including the cushion plant moth, which is specially adapted to survive in the alpine zone. Unlike butterflies, moths can withstand the extreme cold of the mountains, and play an important role in pollinating flowering alpine plants.
Moths are also an important food source for skinks, which live in the shelter of highland boulder fields and low shrubs. Alpine skinks can often be seen basking in the sun to raise their body temperature. Species include the metallic skink, snow skink and southern grass skink.