Why controlling pest plants and animals is a priority for SA and how landscape boards are involved
South Australia’s landscape boards are at the forefront of managing the impacts of pest species.
Pest plants and animals are costing South Australia millions in lost productivity and are having a devastating impact on our environment.
They are most often invasive species, that is, they are not native or endemic to the area and have been introduced either by accident or on purpose and become pests 1 (1).
Invasive species kill and compete with crops, pasture, livestock, and native flora and fauna.
As well as actively killing native birds and animals, invasive species cause significant erosion and damage to native vegetation, watercourses and soils, impacting the structure and function of ecosystems and biodiversity (2). In fact, invasive species are the leading cause of biodiversity loss.
They also carry and spread disease, affecting livestock, decimate valuable pasture, and destroy farm infrastructure, such as fencing, containment yards and shedding.
Invasive animals can also cause irreparable damage to cultural landscapes and other areas of cultural significance (3).
Lastly, invasive pests directly impact many people personally by damaging gardens and garden-based infrastructure that affects their ability to enjoy these personal places or through vehicle accidents and vehicle damage.
Native plants and animals under threat
The number one threat to our native species is invasive plants and animals.
One study concluded that of 100 Australian plant and animal species officially listed as becoming extinct since European colonisation, the larger number of extinctions (45) were caused by invasive species, followed by land clearing (36).
The worst culprit? Feral cats are a main driver of extinctions in Australia, killing a staggering 1.7 billion native animals each year and playing role in most of Australia’s 34 mammal extinctions.
They continue to pose an extinction threat to at least another 120 species.
Economic costs
Globally, the facts and figures are staggering.
Research has found that, alongside dramatic changes to biodiversity and ecosystems, the global economic cost of invasive alien species (including animals, plants and microbes) exceeded $423 billion annually in 2019.
In Australia, articles such as The price of pests: Australia's $390 billion invasive species bill and Pest plants and animals cost Australia around $25 billion a year – and it will get worse point to the economic cost of invasive species associated with losses to agriculture and pest management costs.
A CSIRO article also revealed that nationally, feral cats have been the worst invasive species in terms of total costs, followed by rabbits and fire ants.
Cultural impacts
The presence of invasive species can impact Indigenous people’s connection to Country through direct effects on native plants and animals, and all aspects of cultural landscapes, threatening the continuation of cultural knowledge and practices (Ens et al. 2015).
Invasive weed species impact how Traditional Owners use and manage their land. For example, the invasion of buffel grass (Cenchrus ciliaris) across arid Australia has impacted bush food collection and hunting, loss of bush medicines, access to traditional lands, and ability to conduct traditional fire management. Further, it has had cascading negative effects on cultural transmission to younger generations and maintaining cultural practice (4).
Drilling down: the situation in South Australia
The Department of Primary Industries and Regions (PIRSA) details the pest animals of greatest concern to South Australia, impacting our environment, economy and social amenity.
PIRSA also has a database of declared weeds in South Australia that pose a serious risk to SA’s environment and primary industries.
Managing the risks and impacts of these species with limited resources requires careful prioritisation with tailored management strategies.
This 2023 SA trend and condition report card from the Department for Environment and Water notes trends in distribution for key terrestrial invasive flora and fauna. The invasive fauna list includes: feral cat, wild rabbit, feral fox, feral camel, wild dog, starling, house mouse, and feral deer. For invasive flora, key species are: African boxthorn, asparagus weeds, bridal creeper, opuntioid cacti, Athel pine, boneseed, European blackberry, silverleaf nightshade, gorse, brooms, willows and Chilean needle grass.
How are landscape boards involved?
The Landscape South Australia Act 2019 makes it clear that landowners are responsible for the management of declared pest plants and animals on their land.
Landscape boards work to educate land managers and communities about the risks associated with pest species and the best practices for management.
They also coordinate control programs, working with land managers, local councils and other stakeholders. For example, landscape boards have a role in managing pests on roadsides.
Where required, landscape boards enforce regulations related to pest management, including acting on non-compliance.
They are also responsible for outlining priorities and strategies for controlling pests based on local priorities, and monitoring and evaluating their programs.
What is being done?
Landscape board staff are continuously working on pest plant and animal control across their region.
Landscape boards also collaborate with each other and other partners on cross-regional and statewide control programs when common challenges are shared including these current projects funded by the Landscape Priorities Fund:
- coordinating management of rangeland goats across the SA Arid Lands, Eyre Peninsula, Limestone Coast, Murraylands and Riverland, and Northern and Yorke landscape regions. Led by the SAAL Landscape Board
- a multi-agency strategic response to managing buffel grass involving a cross-regional partnership between four landscape boards: Alinytjara Wiluṟara, Eyre Peninsula, SA Arid Lands and Northern and Yorke. Led by the AW Landscape Board
- the Now or Never cross-regional partnership to control feral deer and goats in the Northern and Yorke, Hills and Fleurieu and Green Adelaide landscape regions and in collaboration with key industry groups and landholders. This includes a big focus on managing peri-urban deer and goats. Led by the NY Landscape Board.
What does success look like?
Landscape-scale success will require coordinated effort from private land managers, industry, community and state, regional and local government agencies. Pest plants and animals don’t stop at property or jurisdictional boundaries. Effective pest management requires action to be taken at the property, landscape and regional
level (5).
SA success stories
We are close to total eradication of feral pigs on Kangaroo Island after using a combination of thermal assisted aerial culling, detector dogs, ground shooting and ground baiting that was informed by forensic analyses for feral pig DNA in creeks and rivers, plus a network of over 500 monitoring cameras, assisted by artificial intelligence.
Feral goats have been all but eradicated from the Montacute area in the Adelaide Hills with a staggering 2,700 of the pests removed since 2020 and an estimated fewer than 50 animals remaining. The environment is showing fantastic signs of recovery.
Cochineal beetles are being used as a natural biocontrol agent to decrease the density and abundance of the invasive Opuntia cacti species across parts of Eyre Peninsula.
Success also looks like the new and more efficient ways of detecting and controlling pests that are being developed, such as using drones to map and spray out weed infestations in the Northern and Yorke region and wireless trap technology to help remove feral cats from Kangaroo Island.
Interested in what’s happening in your region?
Check your local landscape board’s website to find out how your landscape board is working with the community and partners to manage pest plants and animals in your region.
What can you do to help control pest plants and animals?
If you’re a land manager landscape board staff are available to help you plan your approach to pest plant and animal control. They can provide you with technical support, information resources and in some cases incentives to help you control pest plants. Contact your local board to find out more.
The WeedScan app is available to identify and record weeds species helping to build an up-to-date picture of weeds in our landscapes.
Everyone can help collect data on feral animal sightings by downloading the FeralScan app. You can then record the location of feral animal sightings and impacts which are then uploaded and mapped to a central database.
These apps are both crucial to the development of programs responding to increasing pest plant and animal threats.
Footnotes
- Pest plants and animals cost Australia around $25 billion a year – and it will get worse - CSIRO
- Established invasive species abundance and distribution Trend and Condition Report Card 2023, Department for Environment and Water, RC2023_RC_BIO_TER_EstablishedInvasiveSpeciesAbundanceAndDistribution.pdf (environment.sa.gov.au), accessed 1/8/24
- New study highlights invasive species threat to Indigenous culture, 29 May 2024, Invasive Species Council
- Cresswell ID, Janke T, Johnston EL (2021). Overview: Invasive species and range shifts. In: Australia State of the environment 2021, Australian Government Department of Agriculture, Water and the Environment, Canberra, https://soe.dcceew.gov.au/over..., DOI: 10.26194/f1rh-7r05, ISBN: 978-0-646-86427-3
- Hills and Fleurieu Regional Pest Plant and Animal Strategy 2024-2029, Hills and Fleurieu Landscape Board (2024)
