What attempts have been made to control exotic cane toads?
Bufo marinus or the cane toad, was intentionally introduced into the coastal Queensland in 1935 in an attempt to control the cane beetles. Since that time, the cane toad has spread in a westerly and the southerly direction. It is now found throughout the Queensland and has made significant
incursions into Northern Territory and the New South Wales. The major concerns about the toad involve its prodigious appetite and toxicity of all of its life stages to the endemic fauna. There are firmly held beliefs that these characteristics of the cane toads are responsible for the deaths of the Australian wildlife including herpetofauna, mammals and the fish. The toad will now almost certainly establish itself throughout the environmentally sensitive and biologically and commercially important rivers and wetlands of the northern Australia.
Governments have tried chemical, biological, and physical means of controlling cane toads. The difficulties are not only cost and species selectivity, but also efficacy. When one female cane toad can lay upwards of 30,000 eggs, humans are unlikely to effect a long term population control of cane toads if even a few individuals remain. Chemicals which alter reproductive capacity or result in death are likely to lack species specificity and thus affect other species. Biological means, such as introducing a natural predator, have the same potential disaster as did the introduction of a cane toad: the introduction of an exotic has unknown ramifications for any ecosystem. Some work has been done to sterilize males and then release them back into the environment. Any females who then mate with such a male would then fail to successfully reproduce. However, such efforts are all costly and ineffective, especially over large regions. Additionally, cane toads are resistant to the effects of UV r
