Feral dogs (all wild dogs including purebred dingoes, hybrids and wild domestic dogs) are one of the major pests affecting mainland Australian grazing industries. Much of this handbook focuses on sheep farms which, like goat farms, are most at risk of predation from feral dogs. While the effects of feral dogs on livestock can also be significant and widespread, feral dogs are easier to control in livestock areas.
However, local eradication of feral dogs should be pursued in sheep areas.
LEGISLATION AND COMPLIANCE
An assessment will be made by an authorized inspector of the potential impact of the non-conformity in relation to the surrounding land. An inspection of the non-compliant property and surrounding properties will also be carried out to look for signs of feral dog activity and related control works. If the landowner does not comply with the ZCA instructions by the specified date, the directed inspection work will be completed by the staff of the Department of Agriculture and Food and/or by the contractor appointed by the Department.
In both cases, the full costs of the inspection work, including any costs of supervising the work, will be recovered from the land owner concerned.
IDENTIFYING SIGNS OF WILD DOGS
An important factor to remember when interpreting impressions is that the placement pattern of the fore and hind feet can vary depending on the gait and the speed at which the animal travels. Largely depending on running speed, the rear foot imprint may also overlap exactly over the forefoot imprint. This means that the hind paw print can often be the predominant print.
These resting places with their telltale dog tracks can give an indication of the number of dogs present.
IDENTIFYING PREDATION BY WILD DOGS
Sheep more than six months old
External signs of tissue damage due to feeding or scavenging activities can be easily confirmed in a fresh carcass by simple dissection. Depending on the age of the carcass, dissection is often warranted, as bruised tissue can be distinguished from undamaged tissue in a decomposing carcass. Provided the skin is still intact, damage such as stab wounds to the throat can often be revealed by simply pulling out the wool (see Figure 7).
Sheep younger than six months
Again, care must be taken not to mistake decomposing fluids for blood. Any doubts about the cause of serious injuries can be dispelled by examining the carcass. However, sheep with scars from dingo attacks are occasionally discovered, especially when shearing (see Figure 10).
Care should be taken to distinguish bite marks and lacerations from shearing or wire injuries, although dingo damage is usually easily recognized.
WILD DOG CONTROL STRATEGIES
Areas to be targeted for feral dog control, including safeguards against vulnerable businesses, are identified and marked. Ongoing monitoring and recording of feral dog activity and control efforts should be part of normal property management. Evaluation of local and regional levels of dog activity and control effectiveness will be assessed by relevant planning groups.
Baiting is usually the preferred method because it is cost effective, however, trapping is sometimes necessary to remove feral dogs that do not take bait and in areas where baiting is not possible.
ANIMAL WELFARE
BAITING
Despite the known effectiveness of 1080 dry meat bait, there are some advantages in alternative bait materials. All 1080 dry meat baits must be laid in accordance with the conditions of the 1080 risk assessment approval and must have appropriate warning signs. Racks should be of suitable height (waist height) and width (the operator should be able to comfortably reach over) and should be placed in the open to obtain the maximum amount of sunlight and air circulation (Figure 15).
The location of the oat grain should be in the thickest part of the bait and at an angle to avoid penetrating the other side of the bait. This must be done by authorized personnel from the Department of Agriculture and Food or Conservation and Land Management, or pest controllers with appropriate endorsements. Dried baits should be dark, hard on the outside and weigh only 40 percent of their original weight.
Operators should be familiar with 'Guide to the safe use of 1080 gif' (see Further reading). When baiting, appropriate warning signs must be prominently displayed at all designated road entrances to the property, at the ends of property boundaries fronting a public thoroughfare and at other strategic points, for the duration of baiting and for one month thereafter. Public safety will not be endangered by the effects of the poison bait; and.
The victim should rest in a quiet area and be kept warm (or at a comfortable temperature in hot weather). Drying racks must be located away from public access and constructed according to the appropriate design and capacity for the operation planned.
THE ROLE OF DOGGERS
TRAPPING
The trap is now ready to be placed in the ground at your chosen spot (see later). Clear the position of the trap and scratch out the outline of the trap where it will be placed. The trap should be perpendicular to the dog's approach, with the tongue pointing away from you.
This ensures that soil cannot get under the slab and prevents the trap from springing. Heavier paper does not tear well and when the trap is sprung, it can slow the jaws to close. An alternative to using paper over the trap is a foam rubber pad under the plate.
These are good places to set a trap, but you have to choose the position of the trap very carefully. Thorough reading of the sign and special care in trap placement are key elements to successful use of shad sets. This can delay the closing of the siphon, as the springs have to lift the significant additional weight of the soil when the siphon is sprung.
Carefully dig out the hole for the trap and check that the depth of the trap is correct; start again, if not, don't try to correct it later. Verify that the strychnine pad does not interfere with the mechanism or operation of the trap.
OTHER TECHNIQUES/STRATEGIES
There is overwhelming evidence that feral dogs cause economic losses, particularly in the sheep industry, so livestock producers do not need the incentive of a bounty before undertaking feral dog control. The argument is sometimes made that station workers, for example, might be more inclined to hunt wild dogs if there was some kind of financial reward for doing so. In that case, managers may well choose to reward their employees personally, but this does not require a general bonus scheme.
General award schemes divert resources that could otherwise be spent on regional control programmes, producing wider impacts and benefits. One of the dangers of a blanket reward system is that it encourages a scalp-counting mentality. The right action should be to achieve or maintain a reduction in the number of stocks lost to predation.
Bounty systems tend to encourage the hunting of wild dogs where they are easier to find or kill. There is evidence in Western Australia that 1080 baits were not favored in some areas in the past because carcasses were rarely found, and so bounties could not be claimed. Failure to use 1080 bait therefore has the potential to severely compromise efficient and cost-effective feral dog control.
Waiting until the pups are old enough to be collectable potentially increases the number of scalps (and payments) available for claiming, although this runs a high risk of not only losing track of the bitch, but also her litter. Despite the arguments against general bounty systems, there is still some merit in providing financial incentives for the removal of specific individual feral dogs through the so-called 'smart bounty'.
BACKGROUND BIOLOGY OF WILD DOGS
Breeding success can be influenced by social conditions, such as dominance status in a pack and the presence of potential companions to obtain food, as well as prey type and abundance. At this stage, the litter may be split among several adults of the pack. In some parts of Australia, pups seem to become largely independent from the adults at four to six months of age.
There is no evidence to suggest that scent marks repel other wild dogs that may enter the pack's territory from outside. It is rare to see all members of the herd together, and it is more common to see solitary animals or small sub-groups of two to four individuals of the herd. This can happen by killing one of the leaders or by being outcompeted by other members of the group (usually their offspring).
Intruders usually avoid residents, and encounters can lead to desperate chases, which can lead to the intruders being killed by residents defending their patch. Instead, intruders continue to wander, looking for an area where there is no sign of existing dogs, such as scent, markings or howling, and where there is sufficient food and water. For example, although dingoes kill sheep, they seem to prefer to eat other prey, such as kangaroos.
Less common species such as echidna and rock wallabies also appear as minor items in the diet. When prey such as kangaroos have been brought to an end, dingoes transfer their attack from the rear to the neck.
ECONOMICS OF DAMAGE AND CONTROL
FIRST AID FOR 1080 AND STRYCHNINE
Managing the Impacts of Dingoes and Other Wild Dogs', by Peter Fleming, Laurie Corbett, Robert Harden and Peter Thomson. These documents are available on the Department of Agriculture and Food website: http://www.agric.wa.gov.au. The Chief Executive of the Department of Agriculture and State of Western Australia do not accept any liability in negligence or otherwise for the use or omission of this information on this website or any part of it.
