2015
FeralFix: Dr. Jim Mitchell
Feral Deer Management: Rita Island
Report to
Burdekin Shire Council
Chital or Axis deer (Axis axis) are believed to have been
established on Rita Island in the early 1970’s by deliberate
introduction. Over the past five decades the population has
dramatically increased to such an extent that they cause a
range of serious negative effects on agricultural production,
environmental values and social impacts to the Island’s
community.
FeralFix
0447984721
www.feralfix.com.au
The purpose of this review is to establish the extent of problems
that deer cause, describe the control options that are currently
available and to provide recommendations on techniques and
management strategies for best practice deer control specific to
the Rita Island site.
CONTENTS
Executive Summary
Current deer problems
Current deer management
Summary of recommendations
Population management
Damage mitigation
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2
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3
Introduction
4
Chital deer problems
Agricultural production impacts
Disease risk
Environmental impacts
Social impacts
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7
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Deer control techniques
Exclusion fencing
Trapping
Aerial shooting
Ground shooting
SSAA
Deterrents
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9
10
12
12
13
14
Summary
15
15
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Problems caused by deer
Current deer management
Proposed management options
General population management
Damage mitigation
Option 1 - Temporary exclusion fencing
Option 2 – Barrier fencing
Option 3 – Trapping
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Appendix
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1
Executive Summary
Current Deer Problems
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Damage to cane is confined to fringe areas (cane / pastoral boundaries); deer are not
considered an economic problem to all landowners on the Island.
Damage to cane is substantially increased during dry seasonal conditions.
Damage is primarily on young cane causing a potential loss of sugar production.
Individual farmers have incurred considerable costs for deer control infrastructure.
Illegal hunters are a serious and potentially dangerous issue.
There is a potential for serious injury from vehicle colliding with deer at night.
Community unrest between landowners with conflicting views.
Landholder stress with loss of sleep and loss of income needs to be considered.
Current Deer Management
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Individual farmers are undertaking deer control with varying levels of effectiveness.
Fencing and ground shooting are the two methods currently employed.
There are extensive distances of existing deer exclusion fences.
Fencing is not continuous (principally through discontinuous land ownership) and gaps
allow deer through, negating the effectiveness of fences.
Fencing in some instances is substandard.
Shooting is not effective in reducing the problem but move the problem to other areas.
Night shooting is potentially dangerous and has led to neighbour complaints.
Summary of Recommendations
A combination of management options are suitable for the Rita Island site and can be used
individually or in an integrated management process. The recommended management
options can be summarised as either sustained population management and/or sustained
damage mitigation.
A. Population management can best be achieved by using a coordinated group approach
involving all stakeholders using integrated control options. Group action will provide the
basis for long term and more effective deer management.
 The main control option recommended for population management is aerial shooting
combined with aerial mustering within the pastoral areas, as this is the primary refuge
habitats for deer.
 The sparse vegetation is ideal for aerial control as the deer herds are relatively easy to
muster as they will bunch and run together. A helicopter should herd deer into remote
areas using natural features as a barrier to movements. The deer can then be aerially
shot and the carcasses either left, removed or buried or retrieved for commercial use.
 For effective control, a biannual shoot should be organised or if only annually, then just
prior to harvesting and the cane regrowth months should be targeted.
 A secondary population control option is the use of ground hunting by professional
hunters. The SSAA organisation could provide a control option to follow up the aerial
mustering / shooting.
2
B. Damage mitigation involves control options that either limit the access of deer to crops
and/or remove the deer that are causing the damage. A combination of techniques should
be considered.
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To limit the access to cane it is recommended to encourage effected landowners to use
temporary exclusion fencing, either as a barrier to block deer from entering from the
grazing areas or around individual cane blocks, as required.
Fences may only have to be used for short times of the year; when the cane is less then
30cm in height.
It is recommended that appropriately designed electric fences be used as temporary
protection when the risk of damage is highest.
The initial cost of fencing will be recouped over the life of the fence due to decreased
crop losses.
Temporary electric fences are able to be removed to allow for machinery movements
when necessary.
Temporary electric fences need little maintenance as the fences are only used for a
short time when the young cane is vulnerable.
Workshops should be organised to demonstrated deer exclusion fencing options to
interested landholders. Commercial fencing business can provide the expertise to
display effective fence designs.
Construction of bridging fences between the existing exclusion fences to construct a
permanent barrier fence between cane and grazing zones is not recommended due to
high initial and ongoing costs and other problems.
To remove the deer that are causing damage to cane it is recommended to use trapping
as the preferred technique.
Deer can be captured on private properties away from their main refuge areas where
they are not controlled. The owner of the trap has a legal right to the captured animals.
Traps attract deer to a localised area, reducing their damage in other areas.
Large scale corral traps should be established in locations where large numbers of deer
are known to frequent. Landowners could also be encouraged to operate smaller traps especially if incorporated into their existing exclusion fences.
Trapping should be integrating either with the existing exclusion fencing or with new
fences to funnel deer into the trap(s).
An option that commercially utilises the deer carcasses obtained from traps should be
pursued. Trapping costs could be offset if carcasses are commercially sold.
Private companies/ individuals are available to operate traps on participating farms and
take the animals for commercial trade. This should be encouraged as the affected
landowners have no financial outlay; save cost of building and maintaining deer control
infrastructure and benefit from the reduced crop damage.
Commercial operator could construct and operated large corral trap established on
fence lines with the trap gate set into the fence. After capture the deer should be
moved into a holding yard (water, food and shade available) and the trap then reset. In
this way a large number of deer could be continuously trapped until sufficient numbers
warrant their removal to a commercial processing plant. The commercial operator
would construct the trap, provide bait material, monitor activity and remove the deer.
3
INTRODUCTION
Chital or Axis deer (Axis axis) are believed to have been established on Rita Island in the
early 1970’s by deliberate introduction. Approximately 20 deer were initially released
(Standing Committee on Agriculture 1980). The rapidly increasing deer population spread
throughout the tidal areas and mangroves, riparian vegetation along the Burdekin River and
anabranch and throughout the grazing farms on the eastern side of the Island. Small
populations also exist off the island, principally on the banks of the Burdekin River. Chital
deer are water loving animals and are well suited to such an environment. Rita Island was
inspected in 1981 where deer were regarded as a pest by landowners. An estimation of
over 1000 animals was estimated. Another inspection in 2004 estimated over 2000 animals
existed. Aerial survey by the author for this report also estimated between 1000 and 2000
Chital deer now exist on Rita Island, although a scientific rigorous survey has never been
conducted. Over the past five decades the population has dramatically increased to such an
extent that they cause a range of serious negative effects on agricultural production,
environmental values and social impacts to the Island’s community.
Chital deer are declared under the Queensland Government Land Protection (Pest and Stock
Route Management) Act 2002 as Class 2 pest animals. Under this Act land owners must
take reasonable steps to keep their land free of deer and it is an offence to introduce, keep,
feed, supply or release deer without a permit issued by Biosecurity Queensland. Local
Governments are empowered under section 78 of the act to issue a non-complying
landholder with a notice to control feral deer on their property. A maximum penalty of
$80000 is applicable if a landholder does not comply with this notice. The Act also provides
for penalties for the feeding, release or illegal keeping of declared deer. Under the definition
of a feral deer, a deer that is contained within a deer-proof enclosure is not defined as a
feral deer.
4
Chital deer are ecologically suited to the tropical and subtropical areas of Australia and
prefer woodland, forests, and clearings near waterways. Adult males (stags) stand up to 95
cm at the shoulder, while females (hinds) are smaller. Adult stags weigh 75–100 kg, hinds up
to 50 kg. Stags have three tined antlers on a long, upright beam, 55–70 cm. Socially herds
consist mainly of females and their young, together with two or three stags. They are most
active at dawn and dusk and often retreat to shade areas during the heat of the day. Deer
are nervous animals and susceptible to panic when approached so control operations are
difficult. Trapped animals are difficult to manage as they have serious animal welfare issue
when confined or stressed.
The breeding season is non-seasonal, although fertility may be influenced by seasonal
conditions. In Australia, most chital stags are in hard antler in the first half of the year and
the majority of calves are born in the second half of the year. However, it is possible for
stags to rut at any time of the year and calves have been observed in April and May and
from September to November. In good seasonal conditions hinds may display post-partum
oestrus and produce three calves in two years. The gestation period is about 234 days.
Multiple births are not uncommon in native habitat but in Australia fertility may be
influenced by the environment.
Chital deer primary refuge areas on Rita Island are within the cattle grazing areas.
5
Chital Deer Problems
The principal impacts of deer are losses to primary production and the social problems they
cause:
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Direct loss to agricultural production.
Expenditure on control methods.
Social problems caused by illegal hunting.
Motor vehicle hazard.
Disease spread.
Environmental damage.
Agricultural Production Impacts
The principal agricultural industries affected by deer are sugar cane and cattle production.
Cane is only susceptible to damage in the early stages of growth; cane more than
(approximately) 50cm high receive no damage. However financial loss occurs when the
regrowth, after harvest or new plant cane, is browsed continuously so the cane cannot grow
or is severely damaged to such an extent that it fails to mature or has reduced sugar
content. An example of damage documented to one sugar producer who estimated that up
to 8 ha of ratooned cane is damaged yearly.
Damage to young cane.
Cane regrowth grazed by deer.
Continual grazing will eventually kill the cane.
Same age regrowth not grazed by deer
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Deer also have an economic impact on cattle producers as deer are grazers and browsers
that compete with both domestic and native animals for pasture resources. Biosecurity
Queensland (pers. com) estimated that four or five deer consume an amount of pasture
equivalent to one cow. Deer are also known to preferentially select the highest quality
plants in pastures as they require twice as much protein content and significantly higher
total digestible matter than cattle. A cattle producer estimated that deer damage has
rendered a grazing paddock unusable for cattle for the past 15 years due to pasture loss
caused by deer grazing. Deer may also spread weed seeds, harbour cattle ticks and spread
cattle diseases that potentially will incur financial costs. Deer are also known to cause
damage to existing fences as they are highly mobile and pass easily through most cattle
fences. Deer are also known to foul cattle watering points through wallowing which reduce
water quality and may preventing cattle egress.
The need for expensive infrastructure such as fencing to exclude deer can be costly and
maintenance of these fences is also a financial burden on agricultural producers. Other
control techniques such as ground or aerial shooting and trapping also incur continuing
financial burdens on agricultural production as they need to be sustained over a long time
frame especially if the population is not being significantly reduced. Infrastructures such as
traps are expensive to initially build as they need to be robust and enclosures need to be
2.2m high to stop deer jumping out. Maintenance of control infrastructure is also a
sustained financial burden to producers.
Disease Risk
Wild deer are susceptible to a range of exotic livestock diseases including foot-and-mouth
disease, rinderpest, vesicular stomatitis, rabies and blue tongue. Feral deer could play a
major role in the spread of infections and act as a reservoir of these diseases if introduced
into Australia. Deer are also susceptible to a number of diseases and parasites currently in
Australia including cattle tick, leptospirosis and ovine and bovine Johne’s disease. The main
concern is the cost in lost livestock production or the spread of disease to free areas (e.g.
bovine Johne’s disease). However, some of the diseases and parasites also have significant
implications for human health.
Environmental Impacts
Deer may cause severe environmental impacts as they are large animals and are capable of
damaging native vegetation by browsing and trampling understorey and seedling plants,
and by ring-barking young trees by antler rubbing during the rutting season. Due to their
selective feeding, their browsing may influence the variety and abundance of native plant
species and lower diversity and abundance of native plant species. Wild deer can
significantly impact ecologically fragile areas and have the potential to eliminate threatened
plant species from an area. Other environmental damage attributable to deer is the fouling
of waterholes, the spreading of weeds, overgrazing causing erosion (and the subsequent
degradation of water quality in creek and river systems).
Social impacts
Free wandering deer can represent serious problems to the community.
 A large animal up to 100kg on a road at night can be a serious traffic hazard and may
cause motor vehicle accidents and personal injury.
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Rutting deer stags can overcome their fear of humans and may become a problem when
placed in a position where they may use their formable antlers to defend themselves.
Wandering deer have forced some landholders to monitor their crops throughout the
night. The resulting loss of sleep and continual stress of economic loss is detrimental to
their health.
Illegal hunters have been known to traverse public roads and to enter private properties
at night using spotlights and high powered firearms. The resulting disturbance and the
potential injury or fatality to landowners is of serious concern.
The range of views held by landholders on the deer issue is diverse. Views ranging from
deer are a positive resource to deer need to be eradicated has led to in some instances
to disagreements and may cause social unrest in the future.
Vehicle damage due to collision with a single deer (Charters Towers).
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Deer Control Techniques
A number of control techniques are available for deer; all have advantages and
disadvantages and are dependent on the situation and the level of control required. No
single technique may be suitable in all situations; rather a combination of techniques
integrated together is usually the most cost efficient and effective. Control techniques
currently available include:
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Exclusion Fencing
Trapping
Aerial shooting
Ground shooting, bow hunting or dogging
Deterrents
1. Exclusion Fencing.
Deer proof fencing is an effective method of protecting high value crops such as sugar cane.
This method has the main advantages of being humane to deer and non-target species and
offers immediate protection from damage. The main disadvantages of this method are the
initial high cost of construction – although this is offset by the long life time frame of the
fence- the need for constant maintenance and the problem is just transferred somewhere
else.
Advantages of exclusion fencing include:
 Most suitable for protecting valuable enterprises in relatively small areas.
 Effective method of reducing or eliminating damage quickly.
 Can be cost effective, with eliminated or reduced damage over time offsetting the initial
cost of the fence.
 Can be used for localised eradication.
 Low risk to non-target species.
 Electrification of existing fences reduces initial costs.
Disadvantages of exclusion fencing include:
 The deer population may not be reduced.
 High establishment costs.
 High maintenance costs, especially vegetation control.
 Subject to failure with adverse weather conditions or high grass growth.
 Deer will sometimes break through fences if a high value resource is inside.
 Not suitable in large areas or in remote locations.
 Can create problems for the dispersal of native species, especially threatened species
conservation.
 Non-targets may become entangled in the fence.
 Human error in leaving gates open or low maintenance/inspection rates.
Effective deer fencing should be:• Wire netting or chain wire of 17/190/15 or 13/190/30 supported by well-strained top,
bottom and belly wires and pegged securely to the ground. Deer have no problem passing
through conventional wire fences and can crawl under fences when necessary.
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• Sufficient height to deter deer from jumping; deer will prefer to follow along a netting
fence looking for an opening rather then jump. For example some netting fences on Rita
Island deter deer when only 1.2 m high (see below).
However when pressured, deer can jump considerable heights. For maximum protection
fences should be at least 1.8m high or 2.1 m when under high density pressure. Electric
fencing should be a combination of netting and electric offset wires. Netting to one meter
with 2 or 3 offset electric wires up to 1.5m would be an effective deterrent.
• Have strainers and posts made of heavy-duty material (such as hardwood or metal) set
deeply into the ground
• Have gates of similar standard and the same height
• Have cleared fence lines to minimise the chance of trees falling on the fence.
2. Trapping
Trapping is a control technique that can be used in conjunction with other techniques –
particularly fencing. Traps have traditionally be single capture cage traps however large
corral traps are being developed that can capture large groups at a time.
Advantages of trapping over other control methods are
 Trapping is environmentally friendly and humane
 Animals can be harvested for commercial use
 Animals are attracted to the trap site so reducing damage at other sites
 Trapping is particularly suited to small areas of high value agricultural crops
 Trapping does not interfere with normal deer behaviour (unlike shooting) making it less
likely that deer will disperse from the control area.
 The number of animals controlled is known exactly, and carcasses can be removed.
 Trapping is a flexible technique that can be fitted into routine property activities and
flexible in terms of adapting to seasonal conditions.
 Properly designed traps can be moved or re-used as necessary.
 Costs can be defrayed against the sale of deer carcasses.
 Trapping can make use of opportunities as they arise.
 Non-target species that are accidently captured can be released unharmed.
 Trapping can be used when shooting is impractical, or as a follow up to other control
techniques such as aerial shooting.
 Trapping of feral deer has gained increasing acceptance as trap designs improve.
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Disadvantages of trapping are
 The time required and costs to initially build and maintain traps. A large amount of bait
material is required for free feeding purposes.
 Trapping may be labour intensive compared to other techniques and is not a rapid method
of population reduction.
 Sustained control of the population in inaccessible areas may be difficult to maintain by
trapping alone.
 Natural increases due to immigration and breeding may out-produce an ineffective trapping
program.
 Sufficient traps must be distributed in a given area so deer have a high probability of
encountering a trap.
 Not all deer in the area will be trappable. Some may not encounter traps, some may not like
the bait and some will refuse to enter the trap.
 Trapping have animal welfare issues as deer have low stress tolerance (capture
myopathy) and are easily injured when handled. Trapping should follow published
guidelines to improve animal welfare outcomes: (Sharp & Saunders 2007).
Anecdotal evidence indicates that permanent enclosure traps (or corral traps) can be
effective and provide good animal welfare outcomes. A set of guidelines have been
developed in NSW for large corral traps: Make the traps large (e.g. 2–4 hectares) and at a site that deer are known to frequent,
preferably in a shady area with as much natural vegetation as possible.
 Make sure the fencing forms both a physical and a visible barrier to minimise the
potential for injuries. Construct the external fence using 2-metre deer netting on
wooden posts with 3 strands of plain wire on top, making the final height of the fence
2.5 metres. Attach hessian or shade cloth to all fences to a height of 2 metres.
 Provide water, food and shelter in appropriate quantities.
 Use a trail of bait to lure deer inside the trap yard. This may need to be a few hundred
metres long. Suitable baits include lucerne, whole grain oats and molasses.
 Check the trap each day, preferably in the afternoon, from a raised and concealed
position. If deer are inside the yard, close the entrance gates after moving quietly from
the observation position. Always approach the trap from the direction of the gates. This
will prevent the deer being forced into the gate area of the trap, where they will escape.
 Allow the deer to settle in the trap prior to removal or shooting.
 Traps can be left at permanent sites with the gates open and reactivated when further
trapping is required
In most cases, destruction in the trap is preferred to translocation to a deer farm or abattoir,
as translocation of feral deer can be inherently stressful to the deer and significant numbers
of translocated deer die from capture myopathy. Best welfare outcomes are achieved when
the deer are promptly shot in the trap by experienced operators who are able to approach
the deer quietly.
3. Aerial shooting
The high cost of aircraft hire is the major impediment to this technique, although the high
number of deer controlled over a short time period can make this technique very cost
effective in most situations. However the high costs usually force aerial shooting to be
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conducted only spasmodically so it can be ineffective in keeping deer populations at low
levels over a long time frame. Aerial shooting is best used in combination with other
techniques (as part of an integrated control program) to maintain populations at a low level
over a long time period.
Aerial shooting advantages include:
 Labour efficient.
 Unaffected by seasonal conditions.
 Humane and target specific.
 Effective in open terrain, in remote locations or in inaccessible areas where ground
control techniques are impossible.
 Cost effective where deer are in high numbers and observable from the air.
 Numbers controlled are known and can be used for population monitoring purposes.
 Helicopter shooting can be used to form coordinated group control programs.
Disadvantages include
 Dispersal of animals;
 Increasing costs as numbers decrease and in dense vegetation, woodland and forest.
 Ineffectiveness of annual shoots in keeping numbers low. Helicopter shooting should not
be considered as a stand-alone control measure, as it will only reduce the population by
a limited amount and will require follow up with other control techniques.
4. Ground Hunting
Hunting is usually not effective in reducing deer populations unless concentrated on small
isolated populations of deer. Usually only 15% to 20% of the population will be controlled by
hunting alone. Lack of accessibility into deer populated areas and being unable to see deer
due to dense vegetative cover will limit the effectiveness of hunting. Feral deer are cryptic
animals, difficult to locate, are intelligent and will quickly adapt to harassment from hunters
and move to other locations.
However, hunting has been shown to be useful as a follow up technique to remove remnant
populations left over from other control operations. Extensive trapping programs will never
eradicate deer from an area; there will always be difficult to control individuals left behind.
Hunting in this situation, especially in small accessible areas, is a recommended technique
to control the last few individuals.
Hunting is also a low cost alternative (usually at no cost to the landholder) to other control
techniques and as such, some landholders rely solely on shooting as their primary control
option. These landholders regard shooting as an effective technique as they can see the
captured deer or know how many have been controlled. Also, the deer damage usually
diminishes after hunting; generally this is entirely due to the deer being chased into other
areas or onto neighbouring farms where the damage will continue.
A technique using night vision scopes attached to rifles has been shown to be effective in open
terrain. A number of deer in a group may be shot before they disperse. Thermal imaging
goggles and rifle sight are being used in some situations; as the price drops on this equipment
more use can be made of this technology.
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Humaneness of hunting is debatable; aerial and ground shooting if done by competent
marksmen and following the Standard Operating Procedures is considered humane. However,
shooting over extreme distances, incompetent marksmen or being unable to locate wounded
deer can lead to humane issues.
Sporting Shooters Association of Australia.
The SSAA through their Conservation and Wildlife Management branch provides volunteer
self-funded pest animal management to landholders, state and local governments, and
natural resource and conservation organisations. In cooperation with landowners,
volunteer teams of hunters are allocated following a property assessment and the
formulation of an integrated pest management plan.
Strict management practices and guidelines are implemented for each and every field
operation. CWM has developed protocols and standard operating procedures to document
and sign off each project before deploying teams into the field. Occupational health and
safety, hunter ethics and animal welfare are key values that underpin all activities.
Volunteers operate under a strict ‘code of conduct’.
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Members are covered by $20M Public Liability Insurance.
Members are totally self-sufficient when undertaking field operations.
All members must pass accreditation courses which include bushcraft skills, written
examination and high level marksmanship. All of our field volunteers are members
of the Sporting Shooters Association of Australia, Conservation and Wildlife
Management Qld and hold appropriate firearm licences issued by the state
authorities. We also have in our ranks accredited senior first aid officers and
members who have earned many environmental qualifications including the
Property Based Game Management course offered by the Queensland University
Gatton Campus.
Regular ongoing training and development includes technical and practical
competence with firearms, traps, 4WD, remote communications, animal welfare,
hunter ethics, team work and conservation strategies and techniques.
Members have a diverse range of backgrounds and skill sets resulting in some great
outcomes.
5. Deterrents
A range of light and noise deterrents are commercially available. Motion sensors are used
to trigger the mechanism to frighten the animals away. Other devices such as moving fans,
scarecrows, blinking lights, alarm sounds and barking dog sounds can be purchased
commercially. The main disadvantages of these deterrents are that the animals become
accustomed to or tolerated the sound or movements after continuous use. Also other
animals such as wallabies and dogs set off the mechanism.
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The main areas of damage occur on cane farms bordering cattle grazing areas.
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SUMMARY
Problems Caused by Deer
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Damage to cane is confined to fringe areas – cane / pastoral boundaries.
Damage is localised to individual farms – deer are not considered an economic problem
to all landowners on the Island.
Damage to cane is substantially increased when dry seasonal conditions persist. Wet
seasonal conditions generally localise the deer into the more protected pastoral zone.
Damage is restricted to young regrowth or plant cane. However the overall effect of this
damage is a reduction in sugar production from the damaged areas.
Reports of deer currently living in some cane areas and not just in the pastoral areas
may develop into a major problem if dry seasons persist.
Individual farmers have incurred considerable costs for deer control infrastructure.
Deer may use the roads as movement corridors.
Illegal hunters are a serious and potentially dangerous issue. The potential for serious
injury or a fatality exists either through uncontrolled shooting or vehicle accidents.
Ongoing social unrest between landowners with conflicting views.
Landholder stress with loss of sleep and loss of income needs to be considered.
Current Deer Management
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Individual farmers are undertaking deer control with varying levels of effectiveness.
Fencing and ground shooting are the two methods currently employed.
There are extensive distances of existing netting fences
Fencing is not continuous (principally through discontinuous land ownership) and gaps
allow deer through, negating the effectiveness of fences.
Fencing in some instances is substandard.
Shooting is not effective in reducing the problem but tends to move the problem to
other areas.
Most shooting is conducted at night and is potentially dangerous and has led to
neighbour complaints.
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PROPOSED MANAGEMENT OPTIONS
The implementation of a strategic approach to managing feral deer requires the clear
identification of the different goals of the major stakeholders – on Rita Island case this
principally involves pastoral and cane farmers. The essential step is to involve all of the
stakeholders so that different goals can be raised and compromises reached. A
management plan involving all of the stakeholders has a greater chance of success in
reducing the agricultural and social impacts of excessive deer populations. Failing a
compromise being reached with all stakeholders then other management options are
available that can reduce deer impacts to those stakeholders that require deer control.
A number of control techniques are available for deer; all have advantages and
disadvantages and are dependent on the situation and the level of control required. No
single technique may be suitable in all situations; rather a combination of techniques
integrated together is usually the most cost efficient and effective. The recommended
management options specific for Rita Island can be summarised as sustained general
population management and/or sustained localised damage management.
A. General population management requires a coordinated group approach involving
all stakeholders. The main advantage of a group approach is that it can better integrate a
range of control options available, respond more effectively to situations as they arise,
facilitate awareness and peer pressure on those unconvinced of the need for deer
management and make more effective use of resources and available funding. Group action
provides the basis for long term and more effective deer management.
The main control option available that is effective and cost efficient over large areas is aerial
shooting combined with aerial mustering. This option is suitable for use in the Rita Island
pastoral areas as these are the primary preferred habitats for deer and the mainly sparse
vegetation is ideal for helicopter mustering and or shooting. The mangrove areas may be
more problematic; however deer movement in the mangroves are hindered by the
mangrove roots. Mangroves are also a low growing tree so helicopter can hover close to
the ground so mustering deer out of the mangroves is possible. Deer herds are relatively
easy to muster by helicopters as they are very gregarious and will bunch and run together.
Helicopter can be used to herd deer into more remote areas using natural features as a
barrier to movements. Once mustered, the deer can be shot in one location and the carcass
can be either left in the remote area or can be removed or retrieved for commercial use.
This option requires landowner cooperation. As this option will reduce deer impacts on the
cane farms – cane farmers along the fringe areas should also contribute financially –
possibly on a per hectare basis. For effective control a twice yearly shoot should be
organised or if annually, then just prior to harvesting and the regrowth months should be
targeted.
This technique has been used successfully in other areas of the Burdekin and wet tropics
coast to reduce feral pig damage to cane farms. Helicopter companies are available locally
that have experience in aerial shooting campaigns.
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Mustering by helicopter will drive all the deer groups together making aerial shooting more
effective and cost efficient.
B. Damage mitigation involves control options that limit the damage to crops by limiting
access of deer or removal of the deer that are causing the damage. These management
options are not intended for population reduction but damage mitigation.
Option 1. Temporary exclusion fencing.
The simplest strategy is to encourage affected landowners to fence their properties or
individual cane blocks as required. The initial cost of fencing will be recouped over the life
of the fence due to decreased crop losses. Temporary electric fences could be erected when
the risk of damage is highest i.e after harvesting or when planted cane is emerging. Fences
could be lowered to allow for harvesting machinery if necessary. Simple electric fences
designs are available – usually consist of 6 strands; the lowest at 20cm from the ground and
the highest at 1.2m and evenly spaced at 20cm intervals. Bi-polar energiser designs are
most effective.
Temporary electric fences need little maintenance cost as the fences are only up when
required. Standard chemical are required to suppress grass growth but the fences are
usually only required during the dry season so grass growth is minimal. Electric fences can
also be sloped at the 45 degree angle as this increased the chance of a shock as the animal
tries to walks over the fence.
For more permanent fencing; conventional cattle fencing with additional electric wire can
also be used. Adding netting to the fence behind the electric wires will greatly increase their
effectiveness.
A number of commercial electric fencing company are available, representative could be
invited to landowner or shed meetings to advise farmers on the most suitable fence designs.
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An example of an electric fence design suitable for temporary exclusion deer fencing.
Option 2. Barrier Fencing
There are substantial stretches of deer proof fences that are currently constructed,
particularly on the pastoral / cane frontage. These existing fences could provide the
foundation for a single continuous “barrier fence” to block access of deer from their
preferred habitats in the pastoral areas into their feeding areas in the cane areas. The steps
required to undertake this option are:






Establish the location of, and GIS map, the existing deer proof fences along the pastoral
/ cane frontage from the Burdekin River boat ramp on Sandhill Road to Fieldings landing
on the anabranch.
Check all fences to ensure they are deer proof or could be made deer proof.
From this establish the fence gaps that exist and the property owners.
Encourage landholders without fences to build linking deer fences.
Establish a maintenance program – Council or landholder driven.
Establish grids where the barrier fence crosses roads or access to properties.
Establish traps in the fence line where appropriate.
The major problems of this option are the high initial costs associated with construction and
ongoing maintenance cost; who is responsible for maintenance costs – fence damage due to
flooding or fallen trees etc, who has legal responsibility of the fence. There will also be a
need for grids / gates into properties and road crossings. Cane farms would also require
fences to be constructed on the pastoral side of the roads so cane harvesting machinery can
use the roads as turning headlands.
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Example of exclusion fencing for deer
Option 3. Trapping.
Trapping has a number of advantages (see previous section). However the main advantage
in this situation is the deer can be captured on private properties away from their main
refuge areas where they are not controlled. Legally the owner of the trap has a legal right to
the captured animals. Traps also attract deer to a localised area so reducing their damage in
other areas and will reduce the need for night shooting. Large scale corral traps could be
established in locations where large numbers of deer are known to frequent. Landowners
could also be encouraged to operate small traps - especially if incorporated into their
existing exclusion fences.
An option that commercially utilises the deer carcasses obtained from traps would be highly
appropriate as costs associated with building and maintaining traps could be offset if
carcasses could be commercially sold. Private companies/ individuals are available to
operate traps on participating farms and take the animals for commercial trade. This should
be encouraged as the affected landowners have no financial outlay; save cost of building
and maintaining deer control infrastructure and benefit from the reduced crop damage.
An example of an integrating control opportunity that could successfully operate on Rita
Island is a combination of exclusion fencing incorporating a corral trap. For example, an
opportunity exists on the corner of Hodder and Johnstone roads as this is a major
thoroughfare of deer moving at night into cane farms. An extensive section of deer
exclusion fencing already exists. New fencing could be constructed to establish a
continuous fence line to funnel deer into a presently unused grazing paddock.
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A commercial operator could construct and operated a large corral trap established on the
new fence line with the gate set into the fence. As the deer are forced along the fence
trying to get to the cane crop the open gates into the trap would be attractive to deer. After
capture the deer would then be moved into a fenced holding yard (water, food and shade
available) behind the trap and the trap then reset. In this way a large number of deer could
be continuously trapped until sufficient numbers warrant their removal to a commercial
processing plant. The commercial operator would construct the trap, provide bait material,
monitor activity and remove the deer.
Trap designs, materials require and trapping strategies and processes are available from
trapping programs that have been conducted in the Charters Towers area (NQ Dry Tropics
NRM board). A Standard Operating Procedure also exists on trapping deer and should be
followed. Animal welfare concerns should be minimised if these procedures are followed.
Processes that need to be developed include trap security and trap monitoring. Motion
sensing infra-red cameras could be used to monitoring the trap for vandalism or illegal
activities. These cameras transmit images through the mobile phone network so are secure
against cameras being deliberately broken. Cameras also transmit imagers of deer within
the trap which can subsequently be used to close the trap door remotely through the
mobile phone texting system. Local landowners could also physically close the trap doors if
deer are observed to be feeding inside.
An example of deer exclusion fencing used in a deer trap.
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← Proposed location of corral trap
and holding yard
Existing deer fencing
Proposed location of commercially operated deer trap. Existing fences will funnel deer
towards the trap. Additional fences should be constructed to close the gap and force deer
towards the trap and eliminate damage to cane farms in the vicinity.
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APPENDIX
Pest Status Review (2005)– Deer in Queensland.
Qld Government - Peter Jesser
Case study: The Rita Island chital Rita Island lies at the mouth of the Burdekin River. It is a
section of flood plain cut off by an anabranch of the river, which fills during floods. The
island is used for sugar cane, small crops and cattle production. It is about nine thousand
hectares in area. About 20 chital arrived at Rita Island in the late 1970s (Standing Committee
on Agriculture 1980). There is debate as to whether the deer were translocated or arrived
through natural dispersal from up river. The animals multiplied and by the 1990s were in
sufficient numbers to cause damage to grazing and cropping enterprises in the area.
Concerns were regularly voiced in the local media (e.g. Advocate 2004). The Rita Island
chital has spread from their point of origin to occupy the belt of mangroves and tidal flats
extending inland from the ocean front. Chital are a water loving species, well-suited to such
an environment. From the mangroves they move out into agricultural areas in search of
feed during dry times in late winter and early spring. This is the typical pattern where deer
are a seasonal pest. Rita Island was inspected on 23 November 2004. About 200 − 300 chital
were seen in large and small herds at several locations. Signs of chital were seen along all
watercourses, including damage caused to saplings by antler rubbing. Thus the deer are
causing damage to the natural environment as well as to agricultural crops. Based on the
sightings and information from local residents it was estimated that there could be 2 000 or
more chital on Rita Island. The management of these chital has been a contentious issue for
some time. In the past, the owner of the property from which the chital originated has
resisted attempts to control the animals. This has led to confrontations with other
landholders. There has also been a problem with illegal shooters spotlighting in the area at
night. As Rita Island is flat and relatively closely settled, the shooting presents a safety risk
for residents. More recently, the Lower Burdekin Chital Management Group has been
formed to provide a coordinated response to the issue. The owner of the property from
which the chital originated has accepted that some management action is necessary and has
begun to erect deer fences on his property. Illegal shooting has declined since the group
became active. Other landholders have begun to erect deer fences to prevent the chital
gaining access to their properties from the mangroves. Although Rita Island has a substantial
chital population, the deer are in a confined area and eradication is a possibility. The cost of
eradication might be offset if the animals were shot for meat.
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