Frogs and toads are usually some of the most unoffensive creatures in the world of nature. There are, however, some exceptions. One of these is a toad that has proved to be one of the most troublesome animals in the world. The cane toad is a native of Central and South America, but it is not in its home territory that it has caused the trouble.
Man, as usual, is the cause of the problem. If he had left the cane toad in its home range it would not have caused the trouble it has and still is causing. Cane toads are large, nearly two pounds in weight, with a dry, ugly, warty skin. That, however, is not the problem. It loves to eat and will consume a wide variety of things.
It will eat not only insects but birds and small mammals when it can catch them. Its voracious appetite was what made man take it to places where it should never have gone. These include Hawaii and Australia. Both of these locations had an insect problem, so why not bring in the cane toad to consume a lot of the bad bugs was the rationale behind the plan to introduce the toad to both Hawaii and Australia.
Both grow lots of sugar cane and both the French’s and greyback cane beetle are major pests to sugar cane. So bring in the toads. Let them eat the beetles and everything would be alright. Wrong.
The toads were taken to Hawaii first in the early 1900s and then in 1930 100 were shipped to Australia. While the cane toads did eat some of the beetles they soon grew tired of this menu and other kinds of insects, much of which were native and not harmful, and then snails, birds and other animal life were soon being consumed.
Many of these native insects were very valuable in pollinating the many plants native to both Hawaii and Australia. Without the insects many of the plants could not bear fruit and it soon became apparent it had been a major mistake to bring in the toads.
I have failed to mention that the cane toad is a remarkable good breeder and has a very toxic spray called bufotoxin which it uses when it is threatened. Also if a dog or some other animal tries to eat a toad, they will probably be poisoned. On a vacation to Hawaii several years ago I saw many signs stating “Keep your dogs and yourselves away from the cane frogs.”
To show how the toad can multiply, from the 100 or so released in the 1930s it is now estimated there are around 200 million in Australia. They are known as the Australia Outlaw, and millions of dollars are spent each year to try to control the spread of the toads.
The government of western Australia has even called in an army to help stop and eradicate the toads. Fences have been built to try and halt the advance of the cane toad. Australia has even had “Toad Days” where volunteers will go out and capture all the toads they can. Still the toads continue increasing and spreading.
Native animals such as lizards and mammals are being poisoned by the toads. The goanna lizard numbers have decreased by 90 percent since the arrival of the cane toad, and the cat-like guall has also had a large population decline.
It has now gotten to the point where biological measures such as viruses are being used to try and control the toads. Also pheromone gene therapy is being tried. I hope their biological measures will not add another alien to the list of Australian problems.
To show how strong the bufotoxin is, the South American Indians use it as a poison on their arrows. It is also classed as an illegal drug in Australia.
The cane toad loves to eat bees and is a major threat to the bees wherever it is found. You can eat the cane toad, but first one has to know how to remove the poison from the toad. In Belize it is called “spring chicken.” I will still go for the feathered kind of chicken.
The cane toad is a classic example of how man can mess up the world of nature by not letting well enough alone. Will we ever learn?