Living with Wildlife – alternatives to lethal control
Seeing Things Differently
Living with wildlife harmoniously requires a change of perspective. Rather than seeing them as the enemy who eats ‘our’ food, ‘our’ pasture, ‘our’ trees, we should see wild animals as creatures that we share the planet with, as co-inhabitors whose right to go about their business we respect.
Humans are taking increasing amounts of natural habitat away from native species, clearing it and polluting it. It is this destruction that has been responsible for many extinctions and serious species declines throughout the world, even of animals once thought common. It is time the tide turned and some understanding is reached by humans that other species have a right to their natural habitat and food sources, and their own piece of the earth to live on.
Destroying a few individual animals will rarely solve a damage problem. At best, killing of animals provides only a short-term solution and is very labour intensive. If we start to see native non-human animals as deserving of the right to live their lives without constant interference and fear of persecution from the human animal, then we start to seek alternatives to killing them in order to protect our crops and livelihoods from their impact.
Making a decision to use non-lethal methods of wildlife control is an ethical, moral and economic decision. Nonlethal methods, such as fencing, show respect for wildlife and allow wild species to reach a population balance in their natural environment, enabling them to live their lives in peace. It can also make good economic sense!
It is most important to be aware of which species are causing, or are likely to cause, a problem. The solution can then be designed around that knowledge.
Alternatives to Lethal Control: Fencing
Although expensive to set up, good fencing can pay for itself within a season or two for producers of vegetables and fruits, whether it be the home grower, or a commercial producer. Fences should be made from quality wallaby mesh. Fences that are properly constructed and maintained, will keep browsing animals out. It is important to regularly check the lower portions of fences as wallabies and pademelons will get under or through gaps, rather than jumping over.
Fencing should be put in place before crops are planted. Knowing what type of animals are likely to be a problem in a particular area, helps with the design of the fence. Fencing is also an excellent option for protecting pasture. It is most sensible and humane to fence only a portion of the property each year, ie one paddock for a small property. Fencing an entire property all at once will force the overgrazing problem onto the neighbours place, or make the wildlife starve. Fencing a portion of the property each year will allow the animals to gradually decrease their number and get in balance with the feed available to them.
Where wombats are a problem, pushing through fences and creating gaps, wombat gates can be installed. These allow the wombat to pass through, but not other species, without damaging the fence.
Fencing should be designed with care in consultation with neighbours so as to not force wildlife into narrow or dead end corridors.
Note that barbed wire is dangerous for wildlife. For more information on good fence design see Wildlife Friendly Fencing. The state government also has information on fencing methods to keep wildlife out, and while this is a good guide on fence design, there is no need for shooting. There is also a useful guide on how to build wombat gates, but again ignore the reference to shooting.
There is a body of research that shows how cover crops, particularly in regard to forestry seedlings, provide protection from browsing. Bracken, and hop goodenia, which are not favoured by wallabies and possums, have been shown to provide protection for seedlings by hiding them, and restricting access.
Sacrificial or Decoy Plantings
When it comes to fruit trees, one strategy is to plant extra trees to account for expected loss to birds or possums. Another strategy is to plant vegetation that provides preferred food, or makes the area less attractive. For example, research has shown that Silvereyes prefer the nectar from native shrubs and trees to grapes. Ravens and cockatoos prefer open agricultural areas to those planted with structured vegetation.
Browsing Resistant Seedlings
There is continued encouraging research into Eucalyptus seedlings that are unpalatable for browsing. Seedlings sourced from some seedlots have a naturally occurring chemical in a higher proportion that deters browsing. Using less fertiliser whilst the seedlings are in the nursery has also been shown to reduce the amount of browsing.
Individual Tree Guards
In forestry operations seedling stockings are increasingly used to protect seedlings from browsing. They are cheaper and smaller than standard tree guards. They are simply slipped over a seedling prior to planting, delaying browsing until the seedlings have reached a height that they can better withstand it.
Fully enclosing orchards or vineyards in netting has become increasingly popular, and for good reason. Netting eliminates all bird damage. In Tasmania, damage to grapes by Silvereyes is particularly bad and netting has become the widely accepted practice for that industry. Netting has some additional benefits with less blemishes on fruit, sunburn and windrub.
A range of scaring devises exist for birds, with varying degrees of effectiveness. Sonic deterrents used include Bird Frite cartridges, gas guns, bird alarm and distress calls, and other electronic sounds. Guns can also be used to scare, rather than shooting to kill. Other bird scarers use light, reflected sunlight for daytime use, electric lights or hand-held lasers for those that feed at dawn or dusk. These are particularly useful for deterring ducks.
With some bird species scaring can actually increase the damage to fruit crops as birds drop what they are eating, only to return later or move to another area and choose another piece of fruit to start on. So again, it is important to know who is causing the damage before planning the appropriate response.
Early morning and late afternoon are the times to actively pursue bird scaring as this is the main feeding time of most birds.
Visual deterrents for birds, such as modern scarecrows and bird of prey models, are useful deterrents with some species. For best results they should be lifelike, have motion, be very visible and be regularly moved to new locations.
Encouraging birds of prey who will help to scare other birds away is another method. Provide T-shaped perches with a view over the orchard or crop.
Marsupials can be more difficult to scare and will quickly become accustomed to bright lights and loud noises, although some manufacturers claim success with sonic deterrents. There has been some useful research into using foot thumping noises. Foot thumps are how macropods make each other aware of danger.
Using olefactory and unpalatable deterrents may also be useful, particularly in forestry situations. Different mixtures that show promise have been trialled. These may be sprayed onto seedlings to deter browsing. Repellent scents, such as predator scents, have also been used.
Whether it be a forestry plantation, or a vineyard, site choice is important. Sites that provide shelter for browsing species nearby are far more susceptible to damage. Damage is more likely to occur near the edge of plantations or orchards. In some cases it is a case of safety in numbers, with isolated orchards, and those with crops ripening earlier or later than their neighbours, suffering more damage.
Finding Out More
• Go to our Additional
Information to read about ‘How Wildlife Can Help on Farms’,
‘Wildlife in Urban Areas’.
Against Animal Cruelty Tasmania, Tasmanian Conservation Trust & Voiceless © 2012