Victoria is home to a diverse range of wildlife, including many of Australia's most iconic species, species that are not found anywhere else in the world. All of Victoria's wildlife, meaning all native species of birds, mammals, reptiles and amphibians, are protected under the Wildlife Act 1975.
With the population of Victoria expanding and with many residential and commercial developments occurring in response to this, many Victorians find themselves interacting with wildlife on a frequent basis. While living close to nature is a rewarding experience that many people seek, it can also present some challenges.
For example, wildlife may:
- Damage buildings or infrastructure (e.g. houses, factories, sports grounds, fences, dams).
- Threaten human safety (e.g. aggressive wildlife, swooping birds, vehicle/aircraft collisions).
- Damage crops and produce (e.g. damage to cereal, grain, fruit, vegetable, flower crops).
- Damage to the natural environment (e.g. damage to revegetation sites, degradation of natural habitats in a manner that poses a threat to biodiversity).
There are many techniques and measures that can be used to deter wildlife and/or discourage unwanted behaviour. However, some people may not be familiar with these. The Department of Environment and Primary Industries (DEPI) provides guidance to landholders on how to achieve the best outcome for both people and animals. DEPI employs Biodiversity Officers, who have knowledge and understanding of Victorian wildlife and are available to address queries about how to best deal with problems posed by wildlife. There are a several steps that can guide you in resolving wildlife issues:
Correct identification of wildlife
People can sometimes incorrectly identify the species. Different species behave differently, so it is vital to get the species right. Bird and animal identification books can be very helpful. Your local DEPI Biodiversity Officer may also be able to assist you through their knowledge of the local area and the indigenous species present.
Careful assessment of the problem or damage
Before deciding on the need for action, it is important to carefully assess the nature and extent of the problem. Wildlife issues can often be more of a nuisance than a serious problem.
Consideration of the underlying causes
To be able to find an effective solution it is important to determine why the wildlife is causing an issue including:
- Your property may be near an established roosting site,
- There may be attractive plants for the wildlife in your garden and,
- Certain building materials used for your house may be attracting wildlife. If the underlying reasons are not addressed, other deterrent measures are often only effective in the short-term. DEPI Biodiversity Officers may be able to help you to understand species' behaviours.
Selection of an effective deterrent
Through the information gathered in the previous steps, an effective deterrent can usually be found. Often it is not a single method, but a combination of techniques, that is most effective. To effectively resolve an issue it is often necessary to plan ahead, and be consistent and persistent.
The steps in action
A good example of these steps in action is the resolution of the issue of birds damaging a crop:
- If you are growing a crop, you need to identify which bird species are causing the damage.
-Assessing the damage will help to correctly identify which bird species present in the crop is causing the issue.
-By considering the underlying causes you may find that adjoining landholders are experiencing the same issue with their crops at the same time.
-In the selection of an effective deterrent you may decide to use a range of scaring techniques. If adjoining landholders are experiencing the same issue, you may decide to cooperate on an effective scaring campaign so that you aren't just moving the birds back and forth between properties.
The effective mitigation of damage caused by wildlife may require long hours and hard work.
Using lethal control
Using lethal control in relation to a few individuals will rarely solve a damage problem and is often a disproportionate response. At best, killing of animals usually provides only short-term relief and is very labour intensive. Most species of wildlife which may cause damage are adapted to withstand considerable levels of mortality without the population being affected. Thus the capacity of the population to produce young each year is unlikely to be affected by any but the most intensive destruction campaigns. Such campaigns are not likely to be permitted by the Department of Environment and Primary Industries (DEPI).
It is sensible, therefore, in the case of problems which are likely to recur regularly, to look for longer-term solutions to control damage, such as exclusion, different crop placement or other, non-attractive crops, rather than killing.
Direct control of wildlife through dispersal, trapping or destruction of wildlife is managed under the Authority to Control Wildlife system (ATCW). The following fact sheet outlines the ATCW system, how it works and why it is needed.
Summary of permits issued for the destruction of wildlife during 2008
|Black Swan 1||8||108|
|Black-faced Cuckoo-shrike 2||4||40|
|Common Brushtail Possum||6||78|
|Eastern Grey Kangaroo||1,497||58,259|
|Little Black Cormorant||1||2|
|Little Pied Cormorant||1||2|
|Noisy Friarbird 3||10||260|
|Noisy Miner 4||1||130|
|Pacific Black Duck||10||147|
|Red-necked Wallaby 5||34||386|
|Satin Bowerbird 6||3||60|
|Swamp Wallaby 7||171||1,648|
|Wedge-tailed Eagle 8||1||2|
|Welcome Swallow 9||1||15|
|Western Grey Kangaroo||86||2,344|
|Yellow-throated Miner 10||1||47|
Authority to Control Wildlife (ATCW)
- ATCWs always specify a 'Max No.' of specimens permitted to be controlled but that does not necessarily mean that the 'Max No.' actually was controlled.
- ATCWs always specify the 'Control Method' to be used, with an emphasis on non-lethal alternative. Where lethal control methods are used, it is usually as a last resort (where non-lethal methods are ineffective or inappropriate).
It is generally accepted that the prevailing drought conditions of 2008 influenced to some degree the permits issued, as well as the species involved and the maximum number of animals to be controlled.
1 Black Swans were 'eating germinating cereal crops & pasture'.
2 Black-faced Cuckoo-shrikes were eating fruit crops'.
3 Noisy Friarbirds were 'eating fruit crops (including grapes)'.
4 Noisy Miners were 'affecting wildlife subject to a management or recovery program' – Grey-crowned Babblers.
5 Red-necked Wallabies were 'browsing on regenerating native vegetation'.
6 Satin Bowerbirds were 'eating vegetable, nut & fruit crops (including grapes)'.
7 Swamp Wallabies were 'browsing on regenerating native vegetation'.
8 Wedge-tailed Eagles were 'preying on livestock'.
9 Welcome Swallows were 'fouling finished product or other goods'.
10 Yellow-throated Miners were 'affecting wildlife subject to a management or recovery program' – Black-eared Miners.
Relocation of wildlife
It often seems that the best way to solve a problem being caused by wildlife is to catch and relocate the wildlife. Unfortunately, this approach is rarely able to be applied. Some of the reasons for this are discussed briefly here.
Within any habitat, factors such as availability of food, nesting or roosting sites, or frequency of interactions within or between species will determine the numbers of a species which that habitat will support.
Release of an animal into a habitat already fully occupied by that species is likely to result in the relocated animal either not being able to find suitable shelter, being stressed by aggressive interactions with its own kind, or displacing a resident animal. The introduced individual is also likely to have a greater exposure to predators during this period. Starvation is also the likely result of the introduction of an animal to an area in which the food species are not those to which it is accustomed.
As a general rule, if a species does not naturally occur in an area it is a good indication that the area may be unsuitable for that species and should not be considered as a release site. Introduction of a species to an area recovering from fire could result in adverse impacts on the habitat, or in the starvation of the introduced animals due to lack of suitable foods. Introduction of an animal from elsewhere into a population of a sedentary species could result in the genetic contamination of that population, with possible adverse impacts on future generations. With many species of birds and some mammals, relocation makes little sense. Most bird species are highly mobile, and new individuals will continue to be drawn to an attractive food source. Similarly, relocation of a possum from a house roof will simply make way for another possum to move in if the access point hasn't been closed.
Prevention of access to the source of attraction is the sensible solution to these kinds of problems. An exception would be in cases where individual birds or mammals develop unacceptable habits. For example, a Kookaburra which repeatedly attacks windows should be captured and removed. Since relocation of such a social and territorial species is likely to result in a prolonged death, it would be more humane to have it put down, under permit from the Department of Environment and Primary Industries (DEPI).
Finally, relocation may pose a risk of diseases being transmitted to wild populations of a species, particularly if the animal being released has been kept in captivity, and/or has been in contact with other captive animals including domestic dogs or cats. In situations where relocation is likely to result in the death of the animal being relocated; in adverse impacts on other species, or in damage to the habitat of the release area, then lethal control authorised by the Department of Environment and Primary Industries (DEPI), rather than relocation of the problem animal(s), should be considered, if the problem is unable to be resolved by other means.