Problem Wildlife

Welcome to the Problem Wildlife pages of the Department of Environment and Primary Industries (DEPI) internet site. These pages aim to assist in solving problems and/or damage that native wildlife may cause.

The information to be made available through these pages is provided in good faith. Since the behaviour of many animals is difficult to predict, results are not guaranteed, and the Department of Environment and Primary Industries (DEPI) may not be held liable for any claims arising as a result of use of the information on this site.

For the purpose of these pages, wildlife means all birds, mammals, reptiles and amphibians native to Victoria, as well as two introduced species of deer. All native wildlife is protected under the
Wildlife Act 1975.

Research into problem wildlife such as kangaroos and deer is undertaken at the Arthur Rylah Institute for Environmental Research.

Assessment of the problem or damage

Some wildlife can cause significant damage to crops or property, or create a serious risk to public health or safety. For example, the large number of Silver Gulls at some airports can be a hazard to air safety; large numbers of Welcome Swallows roosting in warehouses may present a hazard to workers' health and damage stored goods; cockatoos attacking houses or cereal crops may cause significant economic loss; wallabies browsing newly-established plantations may necessitate replanting.

Sometimes, a problem may seem to be larger than it really is. In such cases, discussion of the problem with another person, and an objective assessment of the facts, may help to put the problem in its proper perspective. Management of the problem often incurs a cost, whether it be in materials, time, altered practices, or some combination of these. This cost should be weighed against the level of damage being caused. On this basis, you can assess whether it is worth your while attempting to solve the problem.

Problems may be more of a nuisance than an economic consideration. Nevertheless, it is still important to assess carefully the real nature and extent of a problem, before deciding on the need for action.

You need to learn which kinds of birds are likely to cause problems. Many bird species which forage within a crop are insect-eaters, and are likely to be beneficial. Their impact on insect populations (including some pest species of insects) can be significant. You should appreciate their presence and encourage them.

Bird identification books are listed in the Further Reading section of these notes. Guides to the identification of mammals, reptiles and amphibians are also listed. If you do not know the name of a species which is causing problems, then you will find these guides helpful. They should be available in most libraries and in larger bookstores.

Combining of methods

Where strategies are suggested to reduce a problem caused by wildlife, their results will usually be more satisfactory if a combination of measures is applied simultaneously. This is particularly the case with bird scaring. You need to be more persistent in the use of scaring techniques than the birds are in attempting to return. Initially, this may involve long hours and hard work.

In the case of birds being attracted by food, they are usually less difficult to deter if you can employ scaring techniques before a feeding pattern has become established. If you are growing a crop, for example, you need to know what bird species are likely to cause damage, and when they first visit your crop, so that you can start a scaring campaign without delay. However, it may be very difficult, or impossible, to keep birds out of a crop if there are no alternative food sources.

Destruction of wildlife

Destroying a few individuals will rarely solve a damage problem, and reduction of the problem is not proportional to the number of animals killed. At best, killing of animals usually provides only short-term relief and is very labour intensive, as well as being distasteful to most people. Most species of wildlife which may cause damage are adapted to withstand considerable levels of mortality without the population as a whole 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.

Authorities to Control Wildlife - Fact Sheet [PDF File - 124.5 KB]

Summary of permits issued for the destruction of wildlife during 2008

Species

Permits

Max No.

Australian Magpie
6
76
Australian Raven
88
2,442
Australian Shelduck
8
220
Black Swan1
8
108
Black-faced Cuckoo-shrike2
4
40
Common Brushtail Possum
6
78
Common Wombat
161
2,698
24
643
Eastern Grey Kangaroo
1,497
58,259
Eastern Rosella
10
148
Emu
95
1,109
Fallow Deer
46
718
Galah
27
2,360
Great Cormorant
1
2
Grey Teal
1
20
Hog Deer
1
2
Little Black Cormorant
1
2
Little Corella
18
1,095
Little Pied Cormorant
1
2
Little Raven
10
285
Little Wattlebird
1
25
Long-billed Corella
38
7,981
Mallee Ringneck
2
20
Maned Duck
168
6,328
Musk Lorikeet
30
1,371
Noisy Friarbird3
10
260
Noisy Miner4
1
130
Pacific Black Duck
10
147
Pied Currawong
35
1,119
Purple Swamphen
1
20
Rainbow Lorikeet
10
310
Red Deer
30
306
Red Kangaroo
9
56
Red Wattlebird
13
305
Red-necked Wallaby5
34
386
Sambar
134
3,321
Satin Bowerbird6
3
60
Silver Gull
20
7,460
Silvereye
14
453
Straw-necked Ibis
1
50
Sulphur-crested Cockatoo
29
2,630
Swamp Wallaby7
171
1,648
Wedge-tailed Eagle8
1
2
Welcome Swallow9
1
15
Western Grey Kangaroo
86
2,344
Yellow Rosella
1
20
Yellow-throated Miner10
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).
2008 Footnotes

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.

ATCW Summary 2008 [PDF File - 61.3 KB]

From time to time, commercial harvest of wild kangaroos in Victoria is raised as an idea by individuals and stakeholders in response to a perceived overabundance problem in a specific local area. There is no commercial kangaroo industry in Victoria and it is government policy not to develop one.This Fact Sheet outlines the reasons why Victoria does not support this.

Harvesting of Wild Kangaroos for commercial purposes - Fact Sheet [PDF File - 105.5 KB]

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. However, this is seldom the case. 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 likely to have a greater exposure to predators during this period. Starvation is likely to result from the introduction of a mammal 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.

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 its 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 very real 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 destruction authorised by the Department of Environment and Primary Industries (DEPI), rather than relocation of the problem animal(s), should be considered, if the problem cannot be resolved by other means.

Please note: Document(s) on this page are presented in PDF format. If you do not have the Adobe Reader, you can download a copy free from the Adobe web site.