Executive summary: invasive plants and animals
Status 2007
Invasive plants and animals threaten all natural habitats of Queensland. They are the most significant threat to the environment after land clearing. Queensland is home to many plants and animals that have been introduced, either deliberately or accidentally, since human settlement. Some of these species have become invasive and can, directly or indirectly, cause detrimental environmental, social and economic impacts.
Terrestrial pest animals and weeds cost Queensland in the order of $700 million a year. Most exotic vertebrate pests (pigs, cats, goats, dogs, foxes, rabbits, deer, horses, cane toads and exotic birds) have long been established in the state and have broad distributions. Overabundant native species, such as kangaroos, wallabies, possums, rats and birds, can also be pests in Queensland. Plague species such as house mice and locusts are also problematic. Recent introductions of concern are the three tramp ant species, red imported fire ants, yellow crazy ants and electric ants. More than 100 species of plants are declared weeds in Queensland; seven of these are terrestrial weeds of national significance. It is estimated that 10 new weeds enter Queensland each year. The plant nursery trade is recognised as a potentially major source of new weed species.
Freshwater invasive species present in Queensland include red-eared slider turtles, 18 noxious and six established fish species and 10 declared species of freshwater plants, including four Weeds of National Significance. The current distribution of declared freshwater plants occurs predominantly on the coast of Queensland and the current distribution of freshwater vertebrate pests occurs predominantly in south-east Queensland. All have the potential to expand their distribution further west and north along the coast.
Currently, no invasive marine species are recorded as established in Queensland and no new outbreaks of invasive marine pests have been recorded since 2003. However, 26 invasive marine pests are listed as posing a potential threat to Queensland's marine environment.
Major contributing factors
Terrestrial pests and weeds degrade the natural environment, decrease primary production, pose human and animal health and safety risks, and lower the aesthetic value of the natural landscape. They have a significant adverse impact on biodiversity.
Invasive freshwater plants and animals can reduce water quality, decrease the size of native fish populations through predation and competition, and lower the aesthetic value of Queensland's waterways. The major factors contributing to the presence of pest fish in Queensland waterways are anthropogenic in nature: these include intentional releases of sportfish and control agents for aquatic organisms such as mosquitoes, use of live bait by fishers, and species released from aquariums and private dams. Biofouling and the dumping of ballast water by ships present major possible pathways for the introduction of marine pests. Yachts and other marine craft that travel through international waters are also potential carriers of marine pests.
Policy response
Strategic and well-resourced quarantine activities provide a sound basis for minimising the introduction of exotic species into Queensland. When introductions do occur, eradication can be successful through coordinated and rapid responses. Similarly, the spread of species already identified as problems can be controlled through strategic activities. For many species already well established in Australia, controlling impacts, preventing new introductions and restricting spread rather than eradication are the only appropriate responses. Biological controls and active containment programs are having a major impact on some weeds and pests. State and Commonwealth initiatives in place to manage the impact of invasive plants and animals are described below.
Declared pest animals are listed in Queensland under the Land Protection ( Pest and Stock Route Management) Act 2000. This Act is the primary legislation providing for and establishing the principles of pest and stock route network management. Under the Act, pest plants and animals can be declared, requiring landowners to remove pests from their land. The introduction, keeping, release, supply and sale of declared pests are also restricted. These restrictions assist in preventing new pest problems, preventing the further spread of pests and controlling current pest problems.
A requirement under the Land Protection ( Pest and Stock Route Management) Act 2002 is the implementation and regular review of the Queensland Weeds Strategy and the Queensland Pest Animal Strategy (see below). The Act also requires local governments to develop and regularly review local government area pest management plans. These plans can identify immediate threats to the local area and target resources accordingly. Local governments carry responsibility for management of pest plants and animals within their areas.
The Queensland Weeds Strategy complements the Australian Weeds Strategy (formerly the National Weeds Strategy) and shares weed management principles. The Queensland Weeds Strategy recognises the need to identify and deal with pathways for weed introduction and spread, and minimise the impact of established weeds. This strategy supports the need for ongoing research into weed control measures, such as the use of biological control agents, and public awareness and education to facilitate early detection and efficient control. Under this strategy more specific weed management strategies, programs and policies have been developed, including the Weed Spread Prevention Strategy.
Weeds of National Significance (Weeds Australia) are identified under the National Weeds Strategy, based on their invasiveness, potential for spread, impacts and socioeconomic and environmental values. Queensland implements management strategies for eight Weeds of National Significance present in the state and is an active participant in control or has a watching brief over another five Weeds of National Significance.
The Queensland Pest Animal Strategy complements the principles of pest management outlined in the Australian Pest Animal Strategy. These principles direct resources to providing leadership and coordination of all stakeholders for pest management, preventing the establishment of new pests, and managing the impacts of established pests. This strategy supports the role of research and extension in improving the efficiency with which pest animals can be controlled. Under this strategy more specific pest management programs and strategies have been developed for wild dogs, feral pigs, mice, locusts and rabbits.
Blueprint for the Bush is a ten-year plan involving the Queensland Government, AgForce Queensland and the Local Government Association of Queensland. Reclaim the Bush is an initiative under Blueprint for the Bush to tackle weeds and pest animals. This pest offensive will target 20 woody weeds, prevention of new threats and weed spread, wild dogs, feral pigs and Indigenous community pest management.
The National System for the Prevention and Management of Marine Pest Incursions is the result of collaboration between the Australian, State and Northern Territory governments, research institutions and industry. The system provides direction for a coordinated approach to managing marine pests in Australia that involves prevention, early detection and rapid response and ongoing control or containment of established pests. This will involve legislation, policy and guidelines for management of ship ballast water and hull biofouling, and programs for communication, research and monitoring.
A state strategy, the Control of Exotic Pest Fishes: An Operational Strategy for Queensland Freshwaters 2000-2005 , promotes an integrated and uniform approach to the management of exotic pest fish. This strategy recognises the need to limit pest fish distribution, gain knowledge of the impacts of exotic pest fish and research efficient, target-specific control measures. This strategy complements the development of the National Management Strategy for the Control of Carp (2000-2005) and the principles of the Queensland Pest Animal Strategy. It is almost impossible to eradicate pest fish populations once they are established in a waterway or river system. Therefore, a major component of the Exotic Pest Fishes Operational Strategy is a community education campaign to prevent the spread of pest fish in Queensland waters.
<<Return to State of the Environment Queensland 2007 content page
Last reviewed 12 May 2011
Last updated 9 February 2009