Integrated rabbit control

Established Invasive Animals Best Practice Management video series

1. Rabbit control in Victoria

Hi, I'm Alex Pattinson, Leading Biosecurity Officer with Agriculture Victoria. Rabbits are one of the most destructive invasive species in Australia. This video gives an overview of the species and the management techniques landowners can use to control them.

The first successful attempt to establish wild populations of rabbits in Australia occurred in the late 1850s. By the 1920s, rabbits had colonised most of Southern Australia, making them one of the fastest spreading invasive mammals anywhere in the world.

Understanding basic rabbit biology and ecology helps you to identify the weaknesses that may be exploited in your control program for better results. rabbits are mostly active from late afternoon to the early morning, often emerging from their war in a few hours before sunset. They gradually graze further from it as it gets darker. Rabbits are shy feeders, and are often wary of new things in their environment. They also prefer to eat plants with the highest nutritional value. Rabbits also have a high reproductive capacity enabling them to recover quickly from poor seasonal conditions, disease outbreaks, and control efforts. One reason for their high reproductive capacity is their ability to dig extensive burrows or warrens. The Warren is the key to success of rabbits in Australia as it protects them from predators and weather extremes. Warrens are essential for breeding as rabbit kittens cannot survive the harsh Australian climate without shelter.

It's well known that rabbits have had a disastrous impact on Australia's economy and natural environment. It's estimated that rabbits cost Australian agriculture more than $200 million in lost production each year. To put the impacts of rabbits into perspective, seven rabbits account for one dry sheep equivalent. Rabbits selectively feed on certain species of plants, which affects the regeneration and recruitment, which changes landscapes over time. Rabbits also compete with native wildlife for food and habitat, and their excessive grazing habits often lead to soil erosion and reduced water quality.

Identifying rabbit activity on your property is the first step in managing this invasive species. Key signs of rabbits include 45 degree cuts on seedlings, rabbit dung, warren and burrow entrances, grazing lines, scratching and ring barking. Familiarise yourself with these signs and keep a lookout when monitoring your property.

Once you've identified rabbit activity, activity on your property or in your area, there's several things you can do. Perhaps the most important thing to remember is the warren is the key to the rabbit's survival. So if you remove the warren, you also remove the rabbit's ability to breed, reestablish numbers and rebound populations. It's important to use the season and climate to your advantage when selecting the timing of your control program as it will increase the effectiveness. The timing of when to use various control methods will be discussed in specific videos in this series.

There is a scientifically proven series of steps you can follow to manage rabbit populations, and it is often referred to as 'The Rabbit Recipe'. The steps include, monitor and coordinate your efforts with your neighbours. Reduce numbers which is best achieved by baiting. Destroy their harbour by ripping warrens, and removing above ground shelter, where applicable. Follow up when needed by reripping or fumigating any warren reopenings. Continue to monitor your property and react when needed. The best time to implement these control methods are summer break for baiting when other feeds are scarce, ripping immediately following baiting in the summer break when soils are friable and the warrens will collapse. Fumitigation to occur as follow up to ripping in the autumn and winter months. We'll provide more detailed information about each method in other videos in this series.

Rabbits are a major issue for landholders across Victoria. Their ability to reproduce quickly means they can also recover quickly after control if it's not done properly. Long-term control is possible if you use the right techniques at the right time and to the right standards. I encourage you to watch the other videos in this series for more detail on the methods I've mentioned. You can also find more information at the Agriculture Victoria website or contact the Customer Service Centre if you have any questions. Enjoy the videos, we hope you find them helpful. And thank you for playing your part in managing invasive animal species.

Established Invasive Animals Best Practice Management video series

02. Monitoring pest animals in Victoria - make it part of your plan

Hi, I'm Jason Wishart. Biosecurity manager with the Established Invasive Animals Team at Agriculture Victoria. In this video, we're going to look at monitoring and why it should be included in your integrated pest management program. Monitoring is often overlooked in pest management programs because it's often seen as a waste of time and money, but this couldn't be further from the truth. Monitoring helps to measure pest damage and abundance, identify hotspots or high use areas in the landscape, confirm if non-target species are present, select the right control tools, ensure your program is having the intended impact, and it allows you to make changes to improve your program.

Two types of monitoring are used to monitor pest management programs, including performance monitoring and operations monitoring. Performance monitoring looks at the impact of your pest management program on the pest animals and their damage. While operations monitoring focuses on the efficiency of your program to ensure that the cost don't outweigh the benefits.

Monitoring can be time consuming, so it's important to be clear about what you want to monitor, when it should be monitored, and how often to confirm you are meeting the project objectives. A range of performance monitoring techniques can be used to monitor pest animals and their damage. They include camera trapping, spot lighting and thermal imagery, activity plots. And you may also record lambing rates or crop yields or look at the response of threatened species populations to your program. No matter what technique you choose, it must be undertaken consistently in terms of site, location, duration, equipment, and personnel. So the results are comparable. Now I'm going to briefly discuss each of the more common monitoring techniques used to measure performance.

In this part of the video, I'm going to run through some of the basics for using activity plots to monitor pest animal populations. So I've got one set out here. Essentially what you need to do is make sure that your plot covers the entire road so that the fox or wild dog can't step around your plot. They've got to actually walk through it. The other thing you need to do is make sure that the plot itself is wide enough, so they don't just jump over. It also needs to be at least a metre in width. And then also you need to set these up at a number of different locations along the property and quite clearly throughout the property so that you get a good representation of fox abundance. Because if you only do one or two plots, it's not really going to give you a good indication. So yeah, making sure that they're at regular intervals and there's enough to cover your property to get good numbers. And then the other thing that's important to do as well is to run it over several nights because on one night there might be a high level of activity that's unusual for some reason, or there might be low levels. So if you've done it over three nights, you can get that average and use that. And then after your control program, you can measure again and compare the same with the same. So it's got to be comparable, making sure that you've done everything in the same way and using the same number of nights and those sorts of things. So when you've set your plot, so this is when you've, you're just setting up, you've, you've created your plot. You make sure that the sand here is all nice and soft. So we've already pre-done one here, but what you can also use is a, is a bag of sand too. If the, if the roads are really hard or the surface that you're working on is really hard, then a, a fox print or a dog print, it won't show up. So you can add some sand to that mix or you can use your rake or a shovel and just really give it a roughing up. So it's nice and soft like you can see here. This is, is really sort of powdery now. So yeah, you set your plots up next morning, come back and have a look and, and record what you've found. And for most animal control programs, presence/absence is really all you need. So the number of plots with fox activity is sufficient. So that's, that's really basically what you have there for activity plot monitoring.

In this part of the video, I'm going to talk about how remote cameras can be used to monitor pest animal populations or even how they can be used to monitor control tools. Now there are a number of different cameras on the market. Some can take video and some can take still, it just depends on the situation and what you're hoping to achieve as to which one you might choose in those situations. There are also a number of different types of camera sets that you can use. So you can use a passive set, which essentially tries to capture the animal in the landscape doing its natural thing. So they're just passively moving through the landscape. And that's generally used to get a count on population. The other thing you can do is use an active set and that's where you'd use an actual lure to bring an animal to a particular area and count them that way. And sometimes that would even be considered, well, what you would use for doing baiting and, and things like that too. Okay, so once you've found the place that you'd like to actually place your camera in the landscape, the next thing you got to think about is probably the, the camera settings and the height of the camera and the distance from, from the actual target as well. So I've got a camera here. It's one of the ones where you use quite regularly. If you are most, most likely you, you're going to be monitoring things like pigs or foxes with, with remote cameras smaller animals often a little bit more difficult to detect. So it's really important that you have them at the, at the right height. So it's essentially a camera detects the heat in movement. So you want to be able to put the camera at the same height as the centre of mass. So with a pig, it's about sort of waist, waist height, a little bit lower than waist height. And you just put it into the post at about there. And you also want to put that camera facing at about 25 degrees to the trail that you think the animal be will be walking down. If you face it at right angles, the animal will be passed before the camera triggers and takes the photo. So it's really important that you sort of angle it along that trail and make sure it, it sort of captures images as the animal walks up and along and, and past. So a little bit different if you're going to be monitoring your bait station or something like that. If it's a bait station, same thing about the height. Really important to have the height right, but the distance from the bait station might be a bit different. So for pigs for example, you might put your camera about, say, five metres away because you want to maximise that field of view and make sure that you get all the animals in the shot. The other thing are the settings on the camera itself, when you're monitoring in the landscape and having animals pass through quickly, you might have your camera set really high sensitivity. So it takes a photo quite quickly and you might take a number of shots during each trigger as well. But one thing that's really important is that no matter what sort of setup and settings that you have, they remain the same for your entire monitoring program. Because if you change the settings, you might get a different detection rate or whatever and it might give you a false reading on population declines or increases. So make sure that that's exactly the same. So if you've set it one way before you're monitoring or before your control program, make sure that they're set the same way afterwards and that you use the same locations and that you monitor for the same length of time as well. So often it's a really good idea to not just to monitor for one night or two nights, but monitor for a length of time and get an average per night per camera. That way you're results will be a lot more accurate as well. And those declines will act be actual declines and not maybe a false reading. So once you've collected your data, the next thing you need to do is, is actually analyse it. And the best way to do that in most situations, particularly for the passive monitoring where you, where getting animals moving through the landscape is to look at the number of passes per animal, per camera, per night. And you average that out over the monitoring period. That's probably the most effective way for analysing camera data. There are other ways too but for monitoring, for a pest control program that's probably the best one to use. The other thing you could potentially do if you're actually looking at visitation rate towards a feral pig bait station, for example, you might then count the number of visits rather than passes. But no matter what it is, always use the same, always analyse it the same way. Consistency is really the key for monitoring so that you're actually comparing apples with apples.

In this part of the video, I'm going to go through some of the basics for spotlight monitoring, and that's really to get an idea of the pest abundance or pest activity on your land before you do control and after you do control. So there are a few things that you got to think about with spotlighting. One thing is probably the target animal. So spotlighting works really well, I guess for rabbits and foxes and to a lesser extent, feral pigs, their eye shine's not so great and you want to have transects predetermined transects as well that you'll monitor on a regular basis. So you'll use the same transect each time. So a transect really is just a path through your property and you want to make sure that that covers a good representation of what your property actually is. So if you've got a bit of bush land and a bit of open grassland and everything else, you want to make sure that that trail that you're going to spotlight covers all of that. Another thing that you need to do is make sure that the time of the night that you do your spotlighting is consistent. The people that you used to do the spotlighting is consistent. And also the actual methodology for spotlighting is consistent. So generally you travel at a certain speed throughout your transects and you do this nice steady arc and you're looking for eye shine. So eye shine from rabbits or eye shine from foxes. To do all this though, you're going to need some equipment and that again will depend on the size of the property that you're choosing or wanting to spotlight or do your monitoring. So if it's a larger property, you might use an actual spotlight, like these are quite powerful and can shine it at a certain distance or a large distance, and you can also use them out of a vehicle. And we've got one here that we use regularly for our rabbit monitoring and it's got a purpose built spotlight cage on the back for safety purposes. The other thing you might use if your property's a little bit smaller is just simply using a torch. You want a fairly high powered torch. And again, so you know if you are using your vehicle, you travelling along at a certain distance, same when you're on foot. You travel long at that certain distance. So it wants to be nice and steady and comparable. So after you finish spotlighting the data that you want to analyse is the number of animals seen or the number of individuals seen per spotlight kilometre. So for rabbits, it'll be the number of rabbits that you saw over a spotlight kilometre and you want to compare that information, your before information to your after information, and hopefully see whether there's been a percentage knockdown. And that's basically it for spotlight monitoring.

The type of monitoring technique used will depend on the target animal, the location, and the equipment and resources available. You should also conduct monitoring over several nights during each monitoring period to allow you to calculate an average as your results will be more accurate this way. Most operations monitoring is achieved by recording the costs associated with the control program in terms of time, resources, and equipment. You may also look at the number of animals removed per technique to determine its cost effectiveness. Once you've completed your monitoring, it's also important to analyse the data. For most pest control programs data analysis does not need to be complicated. Remember, you're only trying to confirm that your management program is having their desired impact on the pest animals and their damage, and that the costs aren't outweighing the benefits. So as previously mentioned, you might calculate the average number of passes per species, per camera per night if using camera monitoring, the average number of individuals per spotlight kilometre, if using spotlighting or the average number of plots containing activity per collection period if using activity plots. Monitoring is essential for any pest management program, as it allows you to confirm if your program is meeting the objectives. And if it's not, it enables you to make changes to improve it. It also helps to avoid any non-target impacts. For further information on monitoring and control methods, please watch the other videos in this series, refer to the Agricultural Victoria website or call the Customer Service Centre. Thanks for watching.

Established Invasive Animals Best Practice Management video series

2. Rabbit control in Victoria - baiting

G'day, I'm Nigel Roberts, Leading Biosecurity Officer with the Established Invasive Animals team at Agriculture Victoria. In this video, I'll be showing you how to undertake a rabbit baiting program on your property. Baiting is one of the most effective ways to reduce rabbit population over large areas and should be considered as a precursor to further rabbit control based around warren destruction. Significantly reducing rabbit populations immediately before ripping will provide better long term management. It's important to remember that baiting alone will not produce long term results as the warrens remain intact and rabbits will continue to breed and reestablish populations.

There are two types of toxins that can be used to bait rabbits in Victoria. These are 1080 and Pindone. 1080 or sodium fluoroacetate is a naturally occurring compound found in some native Australian plants. As such, Australian native animals have evolved with this compound in their diet and have developed higher resistances to 1080 when compared to introduced species that are highly susceptible. Nevertheless, it is important to be extremely vigilant and aim to take all reasonable steps to mitigate risks to non-target species accessing baits. 1080 is an acute poison, which means that animals only need to access the bait on one occasion for a lethal dose. Pindone is a cumulative poison, which means you will need to lay toxic baits over three nights for toxin levels to build up to a lethal dose over time. It is often considered where 1080 is not suitable due to the delayed onset of symptoms and because it has an antidote. That said, many native and introduced species are highly susceptible to Pindone poisoning, so it's important to mitigate risks to non-target species accessing bait sites. Both 1080 and Pindone can be used to manage rabbits as shelf-stable oat baits or perishable carrot baits. Shelf-stable baits are widely available and gives flexibility with baiting timeframes around unexpected delays such as poor weather conditions. Whereas perishable baits will spoil quickly and will be need to used in a short timeframe of purchase. I'll demonstrate how to conduct baiting later in this video.

Landowners must adhere to several legal requirements when using both 1080 and Pindone bait products. All usage, notification of neighbours, transporting, safety, storage, and disposal of both products must be carried out in accordance with the product label and any other relevant state legislation. Furthermore, all 1080 use must also follow the directions for use of 1080 and PAPP bait products in Victoria. 1080 is a scheduled seven poison, so it's purchase and use is restricted to those who hold a 1080 and PAPP endorsed Agricultural Chemical Users Permit. Pindone, on the other hand, is a scheduled six poison, which means it's available for purchase and use without needing a permit.

It's important to monitor your property before undertaking a baiting program. Monitoring helps to identify where rabbits are currently active and it can be used to measure the effectiveness of your program. During monitoring, you can actively search for signs of rabbits including feeding zones, scratchings, warrens, tracks, and dung. Spotlighting is most commonly used to monitor rabbit populations and are often measured as the average number of individuals seen per kilometre. But you may also choose to use remote cameras or thermal imaging equipment. Also talk to your neighbours during this process and consider working together in a coordinated approach. In a baiting program, you may be able to share costs as well as achieving better results because landscape scale control programs are much more effective than individuals working in isolation. In the next part of the video, I'll demonstrate how to bait rabbits.

Baiting can be undertaken at any time of the year, but the best results for baiting is in the summer break, when grasses have dried off and other food sources are scarce. Baiting is worth considering as a control method to crash rabbit populations before ripping warrens. So baiting in the summer break will also mean soils are friable and warrens will have a better chance to collapse when ripped. Have your ripping contractor booked in and ready to go immediately after a baiting program has ended. Waiting too long for a contractor to arrive can provide rabbits time to breed up reducing the effectiveness of your ripping program. The summer break also coincides with a break in the breeding season, meaning young, dependent rabbits are unlikely to be abandoned in the warren by does controlled by your baiting program.

It's important to choose your baiting location carefully to ensure that you are only giving rabbits the best opportunity to access baits and not to non-target species like livestock, native marsupials, or birds. You should be removing livestock from paddocks before conducting baiting. As with most pest control baiting, it's best to bring the baits to the animals rather than trying to attract the pest animals to a particular spot. You will need to identify rabbit grazing zones as this is where you'll want to introduce your baits. So look for areas with short grazed vegetations or fresh dung or scratchings. If you conduct your monitoring in the late evening or spotlighting at night, you should be able to see where rabbits are actively grazing. It's also worth noting that rabbits will not feed in their warrens, so placing baits down the borough entrances will be a waste of your time and money. You can also consider using a remote motion activated camera to help find appropriate baiting sites.

The equipment you'll need to undertake a baiting program is a bait layer or mattock to create the furrows in the earth to lay the bait. The baits themselves in the form of shelf-stable oats or perishable carrots and ample good quality, non-toxic free feed of the same bait type you intend to use. You'll need elbow length PVC gloves and notification signs to place on all the entrances to your property to notify visitors of your baiting program. It's also a good idea to think about how you intend to dispose of any rabbits you pick up after your baiting program.

In this next part of the video, I'll be taking you through the baiting procedure. When you've completed your monitoring, you can start free feeding to train rabbits onto the bait type using non-toxic baits. Free feeding is vital for the success of your baiting program and should not be skipped. It will train shy or neophobic rabbits to the bait type, and will allow you to assess exactly how much toxic bait you will need to use. So large quantities of uneaten bait are not left after the program finishes, which will increase the risk to off-target animals. Free feed over a number of nights leading up to laying poison on your property and fine tune the bait locations each night to where rabbits are feeding. So when you lay the toxic bait, you will increase the chance of only rabbits accessing the baits. Placing free feed out in the environment on your property can be done in two ways.

If you have large areas or high rabbit numbers, you'll need a rabbit bait layer like this one. This is an Ouyen bait layer and most land care groups should have one they can loan out to members. The Ouyen bait layer has a rotating drum driven off the turn of the wheels. It has slots in the drum for the bait to fall out, which you can adjust for heavy or light applications depending on how much bait you need to put out. The bait layer also has a plough disc in the front of the rotating drum that will cut a furrow for the baits to fall into. This furrow does two things. The freshly turned soil will attract rabbits to the site, giving them a better chance to find the bait, and will also allow you to easily bury any uneaten baits after your baiting program has finished. If you don't have access to a bait layer or you're working with a small property or smaller rabbit numbers, you can cut a furrow by hand using a mattock and drop the baits in by hand. Rabbits are most active at nighttime, so place the free feed out towards the end of the day. Follow the product label instructions for how much bait to put out and match that with free feed. Revisit the bait sites each morning to assess the uptake and increase the amount of free feed until you have some remaining the next morning. Rabbits will form strict social hierarchies and dominant males won't allow subordinates to feed if baits are concentrated in one area, so it's better to use lower bait rates, but over longer distances. The process of swailing bait trails through your environment ensures all rabbits will have equal access to bait. If rabbits are located on steep hillsides, it's safer to place bait trails at the top and the bottom of the hill. Be mindful of the rollover risk when driving across a slope. Once you are confident that all rabbits have had access to ample free feed and you have mitigated the risk to off-target species, it's time to start laying toxic baits. Laying of toxic baits is done the same way free feed is laid. A good tip is to reduce your toxic bait rate by a third of your final free feed rate as you don't get rabbits returning to the bait trail and continuing to graze once they've consumed a lethal dose. After you've laid the toxic baits, you must come back the next morning to look for signs of rabbit activity and assess the uptake. If you are using 1080, you may find rabbit carcasses the next morning, but if you're using Pindone you'll need the rabbits to consume three doses over three nights to be lethal. Follow the advice on the product label for more information. It is also a label requirement for you to pick up and dispose of any carcasses you find and bury any uneaten bait the morning after a baiting program.

Baiting is the most effective control method for crashing rabbit populations on your land. Please adhere to all legal and safety requirements when baiting, including following the product label and the directions for use of 1080 and PAPP bait products in Victoria if required. Monitoring and free feeding will help you identify how much bait you need to use in the right areas. It will also help you identify non-target species before you start, and also train shy rabbits to eat the bait. Lay baits in freshly scratched furrow, placed in and around their feeding zones to ensure that rabbits have the best chance to find bait. Also, remember that baiting shouldn't be considered as a standalone control method. Your baiting program should be immediately followed up with warren ripping and fumigation in an integrated program to achieve long-term results on your property. We'll go into more detail on ripping and fumigation in other videos in this series. Thanks for watching, and please visit the Agriculture Victoria website or call our Customer Service Centre for more information.

Established Invasive Animals Best Practice Management video series

3. Rabbit control in Victoria - ripping

G'day, I'm Nigel Roberts, Leading Biosecurity Officer with the Established Invasive Animals team at Agriculture Victoria. In this video, I'll be walking you through the steps to conduct a rabbit warren ripping program to control rabbits on your property. Warren ripping is the best way to achieve long term rabbit control because when you target the warren, you remove the rabbit's ability to effectively breed, reestablish, and rebound.

Before you conduct a ripping program, you must be aware of certain legal considerations. Assess that you are not disturbing any culturally significant areas as causing harm to an aboriginal place can carry large penalties. Certain situations will also require relative permits to remove native vegetation or conduct ripping works on waterways. And you should always use the Dial Before You Dig service to find any services in your project area before you start. If you don't have the machinery yourself, please employ an experienced machine operator.

It's important to monitor your property before undertaking a ripping program. Monitoring helps to identify where all rabbit warrens are located and will help you confirm that the warrens are being used by rabbits and not native wildlife. During this time, you can look for footprints, scratchings, dung and fur and signs of damage. Greatest success is achieved by removing all the warrens in a short period of time as opposed to spread out over a number of breeding events. So ensure you are thorough in your search and you find all warrens. Most ripping contractors will have GPSs in their machines, so marking warren locations with a GPS waypoint and providing that data to contractors will help them find the quickest path to rip every warren. Monitoring should always be used in any rabbit management program to measure its effectiveness. We have a separate video you can watch on how to effectively conduct a monitoring program. In the next part of the video, I'll talk about the warren ripping process.

The first thing you need to think about is timing. You can undertake ripping at any time of the year, but it is most effective when rabbit numbers are low. If you have high rabbit numbers, you should consider conducting a baiting program to reduce numbers immediately prior to ripping. Baiting is best conducted in the summer break when other food sources are scarce and ripping immediately after provides great results, as soils are, friable and warrens will be easier to rip and will have better chance to collapse. We cover the process for conducting a rabbit baiting program in another video in this series. It is also worth considering talking to and coordinating control efforts with neighbours. As landscape scale control programs have far more success than individuals working in isolation.

To undertake warren ripping, you'll need a bulldozer or excavator or maybe both, depending on the landscape and the terrain of your property. The bigger the machine, the deeper they will be able to rip and the more effective they will be at completely collapsing warrens. Dozers are generally quicker and they can rip larger areas as they usually operate with two or three tynes located at the back of the machine. They also have a lower centre of gravity than excavators, so can work in steeper terrain. Excavators are better for ripping warrens in heavy vegetation, rocky out crops, and around farm infrastructure as they are more maneuverable and the single time at the front can operate around and under obstacles. Although it can be a large upfront cost when using large machinery, the benefit for effective long-term rabbit control can pay for itself in just a few years. These benefits are even greater when you work with your neighbours to share costs and cover larger areas.

It's a good idea to employ a spotter to work in front of the machine to mark out the warren entrances with flags or landscape chalk. This will help the machine operator make sure parts aren't missed as the view from the inside of the cabin is quite limited. The spotter can also check warrens immediately after they have been ripped to ensure the job has been successfully completed. Rip lines should be no more than 50 centimetres apart and operators should take time to cross rip if safe to do so. Cross ripping involves making a second series of rip lines at right angles to the first. The operator should also make sure that rip lines reach a depth of at least 50 centimetres and deeper if possible, the deeper the better. Use your judgement based on the soil type and the height of the water table. Or you can ask the machine operator to dig a trench across the first warren to see how deep you should rip before you start. Warrens should also be ripped four metres beyond the extent of the outer entrances. These steps will maximise the chance of fully collapsing the warren. Finally ripped warrens should be then back bladed and track rolled to leave a flat and compacted surface. This makes sure the warren site is less attractive for outside rabbits to return and dig back in, and also helps to reduce soil erosion. Shortly after your ripping program has been completed, it's important to revisit all of the rip sites to fumigate any warrens that may have reopened or re-rip if there are a number of large reopenings. We will cover the fumitigation process in another video in this series.

Ripping is the most effective method at destroying rabbit warrens. Targeting the warrens will break the rabbit breeding cycles allowing you to achieve long term control. You should consider baiting to reduce rabbit numbers immediately before a ripping program to increase the effectiveness of control. Consider working with your neighbours as you may be able to share the cost of employing a contractor with machinery and control programs at landscape scales have greater impact than working in isolation. Choose the right machine to give the greater chance for warrens to be destroyed and use the spotter to help guide the machine and check the success of ripping. You should continue to monitor for reopenings in the weeks and months after ripping. Please watch the other videos in this series for information on other control methods for rabbits and visit the Agriculture Victoria website or call our Customer Service Centre if you have any questions. Thanks for watching.

Established Invasive Animals Best Practice Management video series

4. Rabbit control in Victoria - Fumigation

Hi, I'm Nigel Roberts, Leading Biosecurity Officer with the Established Invasive Animals team at Agriculture Victoria. In this video, I'll show you how to fumigate rabbit warrens to help control rabbit populations on your property. Fumigation is most effective when it is used as a follow up to baiting and ripping as part of an integrated program, or can be considered where ripping is not practical. However, fumigation is rarely effective if it is used on its own. As the internal structure of the rabbit warren remains intact and rabbits can easily dig back in. Please watch the rest of this video to find out how to conduct fumigation.

The most commonly used fumigant used for rabbit warrens in Victoria is aluminium phosphide. Aluminium phosphide comes in a pellet form and releases a poisonous phosphine gas when activated by moisture in the atmosphere and soil.

Landowners must adhere to a number of legal and safety requirements when fumigating rabbit warrens. First, you must possess an Agricultural Chemical Users Permit, and then usage, notification, transporting, storage, safety directions and disposal must be carried out in accordance with the product label and any other relevant state legislation. It's also important that the label states that the product can be used on rabbits as aluminium phosphide is also used as a fumigant for weevils in grain silos.

It's important to monitor your property before undertaking your warren fumigation program. Monitoring helps to identify where the warrens are located and if they are currently being used by rabbits and not native wildlife. You can confirm the warren is being used by rabbits by looking for dung, scratchings, fresh soil excavations, footprints, and signs of damage. It's always a good idea to monitor the general rabbit population before and after your program to confirm its effectiveness. In the next part of the video, I'll demonstrate the steps needed to fumigate a warren.

You can apply fumigant to a warren at any time of the year, but best results are achieved when there is moisture in the soil to create phosphine gas via chemical reaction. As mentioned earlier, fumigation should rarely be considered as a sole technique for controlling rabbits and is best employed as a follow up to warren ripping programs. Ripping is best conducted in the summer break, so follow up fumigation should occur in the following autumn and winter months. To undertake a good fumigation program, you'll need a shovel, water, newspaper, PPE; that is elbow-length PVC gloves and a full face respirator with the appropriate dust and gas canister. The Fumigant product. It's also a good idea to have a purpose built smoker and some flags for finding and marking all the warren entrances. Additionally, a funnel and pipe can help apply the tablets, but this is not required.

In this next part of the video, I'll be demonstrating how to apply the fumigant product to the warren. The aluminium phosphide tablets are applied to each warren entrance. It's important to note that the tablets will slowly start to produce phosphine gas as soon as you open the container, so it's a good idea to have all your equipment ready and the warren prepared so you can apply the tablets to the warren in the shortest time possible. Once your equipment is ready to go, make sure the rabbits are inside the warren by making a lot of noise when you approach the site. You can also use dogs to chase stray rabbits into the warren. Next, you must find all the openings or entrances to the warren. It is vital as entrances left open will allow rabbits to escape to safety as the fumigant gas dissipates. Some rabbits dig purpose-built escape holes that are only used in emergencies like escaping from predators entering the warren. These escape holes are often very small, overgrown with grass, and impossible to find with the naked eye. So to help find all entrances, you can also use a purpose-built smoker. These smokers are modified leaf blowers and work by dripping oil onto the hot exhaust to produce smoke, which is then blown down into the warren. Let the warren fill with smoke and stand back to observe where smoke is coming out of the ground. Make sure you mark all entrances so you don't forget to treat any. After you have identified all entrances, use your shovel to cut back each opening to bare earth. When you close the warren, you want a nice soil-to-soil contact to stop any fumigant gas from escaping. If you leave sticks, grasses, or rocks in the entrance, you might allow the gas to escape reducing the effectiveness of your fumigation. You should cut back all warren entrances before applying the fumigant product. When applying the fumigant product you'll want to work with the wind in your back so the fumigant does not blow back towards you. Also work moving uphill as the phosphine gas is heavier than air and will settle downhill. Always remember to read and follow the product label instructions on how to apply the product to the warren. With your PPE on, open the tablet canister away from your face and place the tablets well down the entrance to avoid accidentally covering them with the soil plug when you close the entrance. At the time of filming, the product label instructs us to apply one or two tablets to each entrance. You can use a short length of polypipe to help get the tablets further down the entrance. It's a good idea to shake the pipe to ensure the tablets aren't stuck in the end before you remove it from the warren. You can also use some slightly scrunched up newspaper to stop the soil covering the tablets, but you must ensure that this newspaper won't compromise the soil plug and allow the gas to escape. You could also wrap the tablet in moist newspaper prior to insertion in the entrance and push them down as far as possible with the handle of your shovel. After you've applied the tablets, you'll need to fill the entrance with ample soil and firm down well to ensure the phosphine gas cannot escape. It's a good idea to leave each entrance as flat as possible to discourage outside rabbits from digging back in. You'll need to continually monitor your site for any signs of rabbit activity in the days and weeks after you have finished fumigating the warren and re fumigate as needed. It can take up to five or six treatments to fully shut down a warren.

Fumigation is best used as a follow up technique after ripping warrens by helping to ensure that warrens remain closed and rabbits don't return. Fumigation is rarely effective if used on its own because the internal structure of the warren remains intact and can quickly be recolonised by outside rabbits that dig back in. Please ensure that you follow the label instructions for safety information and how to use the product. For more information about other rabbit control methods, please view the other videos in this series or visit the Agriculture Victoria website or call our Customer Service Centre for more advice. Thanks for watching.

Established Invasive Animals Best Practice Management video series

5. Supplementary Rabbit control options in Victoria

Hi, I'm Alex Pattinson, Leading Biosecurity Officer at Agriculture Victoria. In this video, we'll look at some of the other management techniques landholders can use to help control rabbit numbers on their property. It's important to highlight that the techniques discussed in this video are considered supplementary and should be used to support an integrated management program that includes baiting, ripping, and fumigation. The supplementary techniques explored in this video have little long term impact on the rabbit population if used on their own, as the warren remains intact for breeding. They are also labour intensive to implement.

Biocontrol has been used to manage rabbits in Australia since the 1950s. Biocontrol agents used include the Myxoma virus and various forms of rabbit haemorrhagic disease, or calicivirus. While these viruses were highly successful upon their release, rabbit populations have since developed immunity or resistance, which has allowed them to bounce back. Biocontrol may be useful in some situations, particularly if it is used as a precursor to ripping if baiting cannot be undertaken.

Exclusion fencing is a non-lethal way to protect your property or specific areas of your property from rabbits. To be successful, exclusion fencing must follow strict specifications such as minimum heights and mesh sizes, as well as burying the bottom of the fence to a certain depth and having an outward facing skirt running along the ground. This type of fencing needs to be maintained regularly to ensure it remains rabbit proof. Nevertheless, fencing may be appropriate for protecting high value areas or crops.

Tree guards are mesh or plastic guards that can be used around individual plants or trees to physically prevent rabbits from chewing off stems and eating seedlings. Tree guards come in a range of sizes to suit different trees and can be useful when trying to protect smaller revegetation areas or orchards. Small tree guards are usually not effective at keeping rabbits out and can be expensive over large areas.

Ferreting is another option that is sometimes used to manage rabbits. It tends to be more of a recreational activity and has little impact on the overall rabbit population. Please consider animal welfare implications of using ferrets and make sure that any rabbits are dispatched quickly and humanely.

Shooting is a technique often used by landholders to manage rabbits, but it is really only effective when rabbit numbers are low or is a follow up to other control methods. Keep in mind, rabbit shooting requires a high level of skill and may not be suitable for all landholders. Shooting can also produce deceptive results. That is, rabbits can learn to avoid spotlights leading to a false sense of success after shooting. Continue to monitor your property after shooting and assess if follow up control methods are required.

Like shooting, trapping can be used when rabbit numbers are low. Foothold traps or confinement traps can be used to trap rabbits on private land, but all trapping of rabbits must be carried out in accordance with requirements of the Prevention Of Cruelty To Animals Act.

Using implosion to destroy rabbit warrens may be suitable for use in environmentally or culturally sensitive areas that cannot be ripped. The process collapses the warren system whilst creating minimal disturbance on the surface. Please note that implosion is expensive and a high level of care and safety is required when using this method. Only authorised contractors can use this method.

The supplementary management techniques explored are best used as part of an integrated program and should only be considered for specific circumstances. For more information, please view the other videos in this series. Visit the Agriculture Victoria website or call our Customer Service Centre for more advice. Thanks for watching.