Keeping Cane Toads Off Your Land
It's no secret that cane toads are one of the most dangerous threats to native Australian wildlife today. These toads, an invasive species not native to Australia, breed quickly and in enormous numbers, and demolish the fragile ecosystems they invade, devouring small animals and plants in huge quantities. They also secrete a virulent toxin in the form of a milky liquid that coats their skin - this toxin can cause irregular heartbeat, burning sensations in the hands and feet and painful skin irritation, and while it isn't normally lethal when ingested by humans, animals, including pet cats and dogs, can easily die after ingesting even a small amount of cane toad toxin.
It goes without saying, then, that you don't want these poisonous little invaders on your lawn. However, this can be a difficult prospect, as cane toads are elusive and able to fit through small gaps in walls and fences, as well as burrow underneath larger obstacles. You are also at risk of being poisoned if you kill them, and even if you kill one from a distance, the toxins in its skin are released into the ground, poisoning plant life and potentially any animal that comes into contact with it. Catch-and-release also comes with its own dangers, and doesn't impact the population - automatic toad traps are also detrimental to local wildlife, and have been blamed for a drop in native lizard populations. Fortunately, there are a few ways of keeping the inexorable march of the toads off your lawn without putting yourself or other wildlife in danger:
Anti-toad fences
Because of the cane toad's burrowing abilities, an ordinary fence will not keep them off your lawn for long - however, they can be modified relatively simply and cheaply to provide a more effective barrier: There are a variety of methods when it comes to toad-proofing a fence, but all of them use some kind of durable sheeting material that cane toads cannot dig through. This is attached to the outward-facing side of the fence, and then laid flat along the ground surrounding the fence (you will want a least a metre of coverage from the fence, to stop toads digging under the whole thing). The sheeting is then secured to the ground, either with pegs, or weighed down with earth and other ground matter (the second option also reduces the physical impact of the fence)
This kind of fencing is time-consuming to construct, but provided your fence has no gaps it should be very secure. If your fence does have gaps, you can extend the sheeting to reach around two feet up the fence, tall enough to stop toads jumping over. Shade cloth is an ideal material to use as sheeting, as it will not perish in the sunlight and is robust enough to withstand inclement weather. Bear in mind that this method will keep out native wildlife as well as cane toads.
Removing shelter and food
Cane toads are attracted to dark, cool, damp areas, and having them present in a lawn or garden makes cane toads more likely to show up. They are also voracious eaters, and aren't picky, happily devouring dog food and decaying animal carcasses. Obviously you're probably not keen on tearing up your plants and filling the fish pond with concrete, but there are a few, less destructive steps you can take to discourage cane toads:
- If you have a pond or other water feature, make sure it is deep with steep sides, as cane toads are attracted to shallow water.
- Reduce usage of automatic sprinklers, or switch to watering plants manually.
- Remove low, leafy vegetation, such as ferns and small shrubs, or place them in steep-sided pots. Replacing these plants with taller plants, trees and climbing vines should minimise visual impact.
- If you use outdoor lights at night, switch to motion-sensing automatic lights - toads are attracted to the clouds of insects that are attracted to lights at night.
- Remove any dead animals such as small birds, and dispose of pet food and water as soon as your pet is finished with it.
Meat ants
Cane toads are rather cocky, in their own way, and when attacked they will generally sit still and wait for the attacker to be driven off or killed by their poison. However, this places them in grave danger from one native Australian creature, the meat ant. The meat ant is completely immune to cane toad toxin, and are fearless attackers, routinely overpowering and devouring prey much larger than themselves with sheer numbers. While native frogs and toads are well acquainted with meat ants and know to steer clear of them, a cane toad will generally sit still and be eaten.
Australian authorities are investigating their use as a widespread toad-killer, but you can use meat ants on a smaller scale to discourage toads from entering your land and killing the ones that do. Obviously, this is a fairly drastic solution, and should only be attempted if you have a terminal toad problem, but the advantage of releasing meat ants to kill cane toads is that meat ants are not poisonous, and their congregational nature makes it much easier to control their spread and, if necessary, destroy their nests.
For more information, check out companies such as Stewarts Pest Control.