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Objective

Recommendation

Key issues

What has been achieved 1998-2003

Tasmania Together

Related Issue Reports

Objective

To reduce the impact of weeds, pests and diseases on the State's biodiversity.

Recommendation

It is recommended that actions are implemented to improve the control and management of weeds, pests and diseases in Tasmania as detailed in the Nature Conservation Strategy 2002-2006 (State Biodiversity Committee 2002), Sustainable Forest Management Reports, and the Regional Forest Agreement Five Year Review.

Key issues

There are some 20 actions identified in the Nature Conservation Strategy, which are grouped under measures to prevent weeds, pests and diseases from entering Tasmania and measures to control weeds, pests and diseases already in Tasmania (download strategy; download State Government response).

This recommendation is supported by analysis and commentrary from three issue reports within the Biodiversity Chapter of this SoE Report. The separation between introduced species, plant pests and animal pests is made because both plant and animal species may be introduced and naturalised in Tasmania without being formally declared weeds or pests.

• Introduced Species: Introduced species are foreign species (e.g. roses, blackberries, foxes, wasps, root rot) that have arrived accidentally or have been introduced intentionally. Once introduced species have established self-supporting populations in the wild, they are termed naturalised or feral. Since Tasmania was colonised by European settlers, hundreds of foreign plants and animals have been introduced into Tasmania. Many introduced species such as crop plants, farm animals and game animals are economically beneficial, and others such as pets (that are managed responsibly) and ornamental plants are harmless to the environment. However, approximately 16% of the naturalised species in Tasmania have become a significant problem to primary production and/or the natural environment and are known as pests. Seven hundred and sixteen naturalised vascular-plant species are known in Tasmania.
   
• Plant Pests (Weeds) and Diseases: A weed can be considered as any plant that is having a negative impact on a valuable resource and requires some form of action to reduce that impact. In most cases weeds are introduced species that are able to out compete native plants, desirable pasture plants or crops due to either an absence of natural disease and pest controls or due to an aggressive capacity to dominate ground such as following soil disturbance. Weeds are not restricted to the land-there are also many species that occur in water. Weeds that affect the natural environment are termed 'environmental weeds' and represent one of the most serious threats to Tasmania's biodiversity. Environmental weeds are plants that either escape, or are deliberately introduced, into the natural environment. They threaten the survival of native plants, animals and communities on land and in water. In 2001, six of the 20 weeds of national significance were present in Tasmania, including: bridal creeper, boneseed, blackberry, gorse, serrated tussock and willows.
   
• Special Features and Native Forests: Thirty-nine rainforest species are known to be susceptible to Phytophthora infection. Fifteen of these are threatened species including six, which are endemic to Tasmania. Mature myrtle trees are susceptible to death from myrtle wilt caused by the fungus Chalara australis. Through Criterion Three of the Sustainability Indicators for Tasmanian Forests (maintenance of ecosystem health and vitality), information is available on the area and percentage of forest affected by processes or agents that may change ecosystem health and vitality.
   
• Animal Pests: An animal pest is an introduced animal with an established self-supporting population in the wild (also known as feral or naturalised) that is a threat, for example to human health, primary production and/or the natural environment. Pests, which specifically impact on environmental values, such as on native plants and animals, are termed environmental pests. The introduction of the fox is one of the major environmental changes since the previous SoE Report, but it also represents a defining event in Tasmania's environmental history. It has the potential to threaten Tasmania's status as a marsupial stronghold.
   

What has been achieved 1998-2003

The following are some of the principal areas of progress in managing weeds, pests and diseases in Tasmania. Further information is available from the Issue Reports through the above links.

Plant pests

• The introduction of the Tasmanian Weed Management Act 1999 provides for the control and eradication of declared weeds and promotes a strategic and sustainable approach to weed management in Tasmania.
   
• All six weeds of national significance present in Tasmania (out of 20 species total) have had draft plans developed. Fifteen of Tasmania's 29 municipalities are fully covered by weed management strategies. Four municipalities are only partly covered by community weed management strategies: Break O'Day, Central Highlands, Meander Valley and West Coast.
   
• Tasmania's Weed Alert Network was established in 1999 in order to increase the chances of finding newly introduced or recently established weed species.
   
• WeedPlan, which is Tasmania's weed management strategy, was developed in 1996. The strategy is being reviewed in 2002. One of the key strategic actions of WeedPlan is to develop a procedure and program for ensuring WeedPlan is reviewed at appropriate intervals. The outcomes of the review will assist in defining the future direction of weed management in the State.
   

Animal pests

• The State Government has formed The Fox Free Tasmania Taskforce to prevent the establishment of foxes in Tasmania.
   
• The Carp eradication program has been ongoing at Lake Crescent and Sorell.
   
• A study of the impact of feral pigs on Flinders Island (Underwood 2000) has been undertaken, and eradication measures commenced in cooperation with the local community.
   
• Vertebrate pest management on Macquarie Island has been conducted since 1974 and has culminated in the eradication of feral cats on the Island. Also quarantine strategies have been developed to prevent further introductions to the island.
   
• An Australian Government-funded goat eradication program has been carried out in key areas of the State during the past five years and has achieved localised success.
   
• A two-year project was commenced in 1999 by the University of Tasmania to examine the impact of feral Pacific oysters on assemblages of native species.
   

Tasmania Together

Relevant Tasmania Together goals and standards for 'Biodiversity' are listed in the linked file. The Tasmania Together Progress Board reported on progress toward targets for benchmarks set (Tasmania Together Progress Board 2003). Indicators, targets and baseline data are available in the latest Progress Report June 2003. Further information, including progress report updates, is available from Tasmania Together.

Related Issue Reports