Western Shield
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Western Shield, managed by the Western Australia's Department of Environment and Conservation, is a nature conservation program, safeguarding Western Australia's native animals and bringing them back from the brink of extinction. Set out in 1996, it was at the time the largest and most successful wildlife conservation program ever undertaken in Australia and as of 2006, it is still the largest wildlife conservation program.
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[edit] Conservation practices
Between the 1920s and 1950s scientists developed a poison called Sodium fluoroacetate (commonly called 1080 poison). Subsequently it was found that the same poison grew naturally in many plants in the south-west of Western Australia and that further, many of the native mammalian herbivore fauna of the region had evolved with a natural tolerance to the poison. The plants, in the genus Gastrolobium, were commonly called "poison pea"; farmers and graziers often suffered livestock losses from animals which had wandered into and grazed in areas containing the plant.
During the late 1980s and early 1990s a program of fox control was commenced using dried meat baits and sausages laced with 1080 poison. The program was found to be effective by allowing native species' populations to increase by removing the introduced predators, namely foxes and feral cats. Poison coated oats and carrots also help control herbivorous invasive species, including rabbits and rats.
Research and monitoring has shown a dramatic increase in native animal numbers. For example, trap success rates for medium-sized mammals (particularly Woylies) in the Jarrah forest of Kingston Block, near Manjimup, revealed a sevenfold increase in native mammals since baiting began in 1993.
770,000 baits are dropped every 4 months from a Beechcraft Baron twin engine light airplane.[1]
[edit] Biological resurgence
After research showed that fox control led to a dramatic increase in native mammal numbers, in 1996 Western Shield was introduced and the baiting of foxes all over the southwest of Western Australia commenced. In most national parks, nature reserves, and state forests, the total area that Western Shield baits every three months is now up to almost "half the size of Tasmania". From Western Shield's baiting regimes, all native mammal species increased including Numbats, Common Brushtail Possums, Tammar Wallabies and Quokkas. This has allowed species with dangerously low populations to recover.
As well as aerial baiting, in 1996 a program began to translocate or reintroduce native species to ecosystems where they were previously found, but no longer occurred. Reintroductions are of animals either taken directly from a wild population or from a breeding center. Western Shield has carried out reintroductions into many reserves across Western Australia, including privately-owned conservation reserves of organisations such as the Australian Wildlife Conservancy.
[edit] Species reintroduced
From 1996 to about 2000, 60 translocations had taken place in Western Australia, with over 17 species (13 mammals species, 3 bird species, and a few reptile species) involved. The translocations have not only occurred in the southwest forests but also the Monte Bello Islands, the Pilbara, Kalbarri, Shark Bay and all over the entire state, and interstate reserves and also privately owned conservation reserves.
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Mammal species |
Bird species Reptile species |
[edit] Species taken off the endangered species list
Western Shield has been so successful that three native mammals species have been taken off the list of Western Australia's list of threatened fauna – through the Wildlife Conservation Act 1950. The species taken off "Schedule 1 – Fauna that is rare or is likely to become extinct" were the Quenda (Isoodon obesulus), the Tammar Wallaby (Macropus eugenii) and the Woylie (Bettongia penicillata). The Woylie was also taken off the list of Australia’s threatened fauna – through the Environment Protection and Biodiversity Conservation Act 1999, it was taken from the "Endangered" Category and is not even on the list any longer as it is not deemed in "danger of extinction'. The Woylie was also taken off the "IUCN Red List of the World’s Threatened Fauna" as "Endangered" and downgraded to "Lower Risk / Conservation Dependent". Western Shield’s success for having the Woylie de-listed as "Endangered" on the state, national, and international levels is a first for any species in the world to be taken off either the state, national, or international level of ‘Threatened Species’ due to successful wildlife conservation efforts.
[edit] References
- ^ Western Shield. Department of Environment and Conservation. Retrieved on 2008-02-17.
[edit] Further reading
- Possingham,Hugh; Jarman, Peter and Allen Kearns. (2004) A review of the Western Shield Program. Conservation science Western Australia, Vol.5, no.2 (Dec. 2004), entire issue.
- Bouncing back Landscope, Spring 1998, p. 28-35,
