Managing invasive plant and animal species across the landscape is critical to the success of conservation efforts in the Great Eastern Ranges. GER’s emphasis on bringing together diverse stakeholders, including government departments, scientists, private landowners and other members of the community, provides a unique opportunity for integrated management of invasive species across many different tenures.
Invasive species and connectivity
Controlling invasive species is a vital component of connectivity conservation. Ongoing management of weeds and pest animals within vegetation linkages provides a safer environment for native species and makes it easier for them to move across the landscape. Considering the increased risk of aiding the spread of pests and weeds when planning corridor linkages, and implementing active management programs, will also help prevent invasive species from moving along habitat corridors.
Projects such as GER can co-ordinate invasive species control over multiple properties, enhancing connectivity outcomes. For example, when pest control activities are conducted in core habitat areas, such as national parks, a buffer zone can be created by controlling pests on surrounding properties at the same time. This reduces the chance of pests subsequently moving back in from neighbouring areas and re-establishing populations.
Planning weed and pest animal control
As in many parts of Australia, invasive animal species and weeds in the Great Eastern Ranges have significant impacts on native species and ecosystems. Depending on the species, location and resources available, a range of control methods may be used to manage populations and restrict movement.
Good conservation planning is an important way of managing invasive species. Protecting intact habitats from disturbance helps to reduce the threat posed by weeds and pest animals. This is because healthy ecosystems containing a diversity of species tend to be more resistant to invasion than degraded and disturbed ones.
The risk of increased impacts from invasive species can also be reduced by strategically planning linkages across the landscape. This involves assessing the desirability of any links before investing in them, and designing projects to maximise the size and connectivity of habitat remnants. To limit the spread of invasive species, it is essential to create healthy and resilient habitat within linkages by using a wide range of locally-sourced plant species, incorporating existing native vegetation features into the corridor, and actively managing invasive species within the corridor. As the edges of habitat areas tend to be most affected by invasive species, the design of corridors is important. Wider corridors provide a better habitat for native species than narrow ones, which are mostly ‘edges’, with little undisturbed vegetation.
When developing management plans for weeds and pest animals, it is important to consider the interactions between the target species and other elements of the ecosystem. For example, there is growing scientific evidence that dingoes occupy an important niche as an apex predator in many Australian ecosystems, and can suppress populations of smaller predators such as foxes. Control measures to reduce dingo numbers can therefore result in serious impacts on wildlife due to increased fox populations. Weed species such as Lantana can also play an important role as habitat for small birds and other wildlife, especially in landscapes with little native vegetation. It may therefore be better to leave some patches of this weed intact, at least until native vegetation has regenerated nearby to provide alternative habitat. As there are no simple solutions to these complex interactions, it is vital that detailed knowledge of the local environment is incorporated into invasive species management.
Where to get further advice
More information about invasive species control can be obtained from regional biosecurity and natural resource management authorities, or State Agriculture and Environment departments. The Australian government provides a list of Authorities responsible for weed control in each state and territory. Other useful resources include: