Endangered Species Handbook

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Forest

Australia

     Australia's temperate rainforests are very similar to those in New Zealand, and fragments persist in portions of eastern and southeastern Australia.  Relatives of the Kauri, the Nothofagus beeches, and podocarpus trees are native.  An exciting botanical discovery was made in one of these forests in 1994.  Named the Wollemia Tree (Wollemia noblei) after the national park where it was discovered, it is a member of the Araucaria family and somehow escaped attention until 1994.  A species familiar to botanists through fossil records, it was thought to have become extinct 50 million years ago (Wilford 1994).  A botanist noticed an unusual tree in Wollemi National Park in New South Wales, southeastern Australia and, when he investigated closely, found its fern-like leaves and other proof that it was indeed a living fossil (Wilford 1994).  About 23 of these "living fossils" have been located in the park, the tallest towering 130 feet with a 10-foot girth and the species is being propagated by the Australian government.  At a press conference soon after its discovery, Ken Hill, botanist at the Royal Botanic Gardens in Sydney, exhibited a fossil imprint of the Wollemia's fern-like leaves next to the living branches for news media, stating that it was one of the outstanding biological discoveries of the century (Wilford 1994).  Pictures of these trees were shown on television news programs around the world, an indication of the new appreciation being accorded such natural wonders.  These massive pines have dense, waxy foliage and knobby, dark bark with strange-shaped branches growing from the trunk (Wilford 1994).  They were found growing in a secluded area of little more than an acre, deep in the national park, where high humidity and moisture probably protected them from fire and provided ideal habitat (Wilford 1994).  Had these priceless trees not survived in a national park, they might have been cut for firewood or commercial logs long ago.  Wollemi National Park's protection was considered a great triumph for Australian conservationists.  It contains the country's largest area of undisturbed forest--more than 486,400 hectares (1,201,894 acres) (Campbell 1989).  The Colo River, the last unpolluted waterway in New South Wales, flows through the park.  Other trees in this park include tall eucalyptus, which predominate; Snow Gums; Mallees; and pockets of rainforest in gullies (Campbell 1989). 
 
     Four species of Australian Podocarps are listed by the 1997 IUCN Red List Plants.  They range from Queensland's rainforests to temperate rainforests in New South Wales and Tasmania.  Such forests, with their tall, evergreen trees and understories of tree ferns, are very rare today as a result of climatic change, a gradual drying of the continent and logging.  Eucalyptus trees, which can withstand a dryer climate, gradually increased in range in Australia's temperate rainforests since they appeared in the Oligocene Epoch 35 million years ago (Vandenbeld 1988).  They first colonized forest edges and flourished in open woodlands, then grew into entire forests growing from Queensland south to Tasmania, having radiated into 500 species  (Vandenbeld 1988). 
 
     From New South Wales south to Tasmania, Nothofagus beech forests have been edged out by eucalyptus but remain in a few areas, a glimpse of the past.  Mosses, ragworts, rotting logs, ferns and tree ferns carpet the forest floor, similar to those growing farther east in southern New Zealand (Vandenbeld 1988).  European colonists logged these forests to clear the land for farms and grazing.  The ancient eucalyptus, with their massive trunks, dwarfed the teams of oxen that dragged out the logs.  This primeval forest is now almost gone.  A 19th century artist, Isaac Whitehead, depicted a magnificent old-growth forest being logged in a dramatic painting showing trees that must have had circumferences of well over 50 feet.  If not for the huge stumps that remain, one might have doubted that they actually existed (Vandenbeld 1988).
 
     Forty percent of the country's forests have been cleared, including 75 percent of the rainforests in northern Queensland and 90 percent of both the dry mallee of the south and the eastern temperate woodlands (Parfit 2000).  Logging had a devastating effect on the continent's woodland mammals who depended on the forests for survival.  Of 144 marsupials inhabiting Australia 200 years ago, 21 are extinct, and a total of 88 Australian marsupials are listed in the 2000 IUCN Red List Species.  Many of these were forest species.  Australia has had more mammals become extinct over the past few centuries than any other country in the world.  The majority of forests in Australia did not revert to second-growth but became grazing land, plantations, agricultural fields, or tree farms of non-native pines for pulpwood (Vandenbeld 1988). 
 
     The eucalyptus forests that came to dominate many of Australia's woodlands are interspersed with savannah in the dryer north.  In the south, they grow in dense, moist woodlands, with tree ferns and mosses as ground cover.  Among the most characteristic trees of Australia, almost all the great old specimens are gone.  Few Australians have ever seen a gigantic, 400-year-old eucalyptus tree, so massive that it takes 15 people to embrace its girth, but such trees were once common (Sharp 1995).  It takes 200 to 300 years for a eucalyptus to form nesting holes that provide homes for possums, gliders, bats, snakes, birds, parrots and other creatures that were once prolific in Australia (Sharp 1995).  The tallest trees in Australia, many eucalyptus stand more than 300 feet high (Attenborough 1995).  In 1880, just before cutting it down, a surveyor measured a eucalyptus that stood 375 feet tall; another inspector around the same time told of a fallen trunk that was 435 feet long (Attenborough 1995).  Had this been confirmed, it would have been the world record for the tallest tree ever measured (Attenborough 1995).  Their straight, unlimbed trunks rise to great heights before branching. Settlers cut them for building materials and railroad ties, clearing vast areas and threatening many species.  An astounding 175 species of the genus Eucalyptus are listed on the 1997 IUCN Red List Plants
 
     In central Queensland, 5 billion eucalyptus trees were cut to create permanent grazing land for up to 2 million cattle.  Up to half of the trees in 100 million hectares in this Australian state have been cut (Arnold 1994).  The last forests of Queensland are being cleared for livestock and agriculture at one of the highest rates of deforestation in the world, estimated at 840,000 acres a year (Parfit 2000). 
 
     Koalas (Phascolarctus cinereus), native to eastern Australia's eucalyptus forests, are entirely dependent on the leaves of these trees for their food.  Most animals avoid eucalyptus because the leaves contain toxic oils, but Koalas have the ability to detoxify these oils, which also gives them a natural insect repellant (Berra 1998).  They eat about 36 species of eucalyptus and obtain most of their moisture from dew and the leaves (Berra 1998).  Forest clearing has had a disastrous effect on their populations.  The last large population of Koalas in southeast Queensland was decimated by construction of an expressway, over vehement opposition from citizen groups (Arnold 1994).  Likewise, in the state of Victoria in the southeast, Koalas have been reduced to a few remnant colonies as a result of hunting, development, tree cutting, highways, fires, droughts and predation by dogs and foxes.  At least 4,000 Koalas are reported killed each year, and about 2,500 of these die after being struck by cars near urban areas (Berra 1998).  They have also been victims of a variety of illnesses, including Chlamydia, which causes reproductive failure, pneumonia, blindness and other ailments (Berra 1998).  They have declined so dramatically that in 2000 the species was listed as Threatened on the US Endangered Species Act.
 
     Outside of protected areas, the last old-growth forests in New South Wales are being cut.  The government accorded a giant multinational corporation, Boral, a contract to cut 500,000 tons of woodchips in the mid-1990s. (Arnold 1994).  This logging will remove virtually every native forest not protected in national parks in northeast New South Wales, according to Sue Arnold, Coordinator of Australians for Animals (Arnold 1994).
 
     Victoria still retains some old-growth forest, home to a host of rare animals.  Old eucalyptus tower over tree ferns, sassafras, mountain pepper and mosses.  In 1999 and 2000, loggers began cutting one of the last of these forests known as the Goolengook Forest (EarthFirst! Journal 2000).  Aborigines have been able to stop logging in some traditional areas, including East Gippsland, Victoria, but the delicate and endangered native marsupials inhabiting most of these forests may not survive for long. 
 
     A strange mammal of Victoria's eucalyptus forests is Leadbeater's Possum (Gymnobelideus leadbeateri).  Native to the Central Highlands, it lives in colonies in tall, old-growth eucalyptus trees (Strahan 1995).  Thought extinct, this marsupial was rediscovered in 1961.  With a tail almost twice the size of its body, huge black eyes and a stripe down its back, this possum looks like a cross between a squirrel and a skunk.  Each night, it emerges from tree hollows to climb tall trees in search of insects.  Forest clearing has destroyed much of its mountain forests (Nowak 1999).  Only about 5,000 or fewer Leadbeater's Possums survive, and the species continues to decline as logging clears its habitat (Kennedy 1992).  Its dependence on large trees, especially those 300 or more years old which have large tree holes for their nests, has made it very rare (Strahan 1995).  Specializing in finding crickets, beetles, spiders and other arthropods beneath the shedding bark of eucalyptus and other trees, it may require, for an as yet unknown reason, a particular species of tree cricket which shelters under the bark of a certain type of eucalyptus (Strahan 1995).  This possum also eats gum and tree sap.  Less than 3 percent of its total range of 4,000 square kilometers is protected in nature reserves, and 75 percent is located in timber-production forests where tall, old trees are likely to be cut (Strahan 1995).     


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