Defining Moments in Australian History: Introduction of cane toads
Sugar cane was brought to Australia by the First Fleet in 1788. There were repeated small-scale attempts to grow the crop throughout the early part of the 19th century, some of which were successful enough to encourage repeated attempts further north.
Captain Louis Hope, the person widely regarded as the father of the Australian sugar industry, raised a viable crop at his property in Moreton Bay, Queensland, in 1862. Two years later he established a sugar mill. From there the sugar industry grew as it followed the colonisation frontier, reaching the far north of Queensland by the 1880s.
Establishing the industry was not easy. Drought affected crops periodically. However, the biggest problem was the larvae of native beetles, which ate the roots of the sugar cane.These became collectively known as cane beetles, and it would take decades for scientists to identify precisely which beetles were the problem.
After lobbying by cane farmers, the Bureau of Sugar Experiment Stations was established in 1900. These were
run by entomologists who worked on the cane-beetle problem by experimenting with different chemical methods
of pest control.
Historian Peter Griggs speculates that scientists’ success in controlling prickly pear with biological instead of
chemical means encouraged the Bureau to try the cane toad.
In 1932 Bureau of Sugar Experiment Stations plant pathologist Arthur Bell attended a conference in Puerto Rico where he learnt of, and then reported on, the apparent success of an American toad species in reducing populations of cane beetles.
Three years later, in June 1935, Bureau entomologist Reginald Mungomery travelled to Hawaii, where the cane toads had been introduced from Puerto Rico. Mungomery captured a breeding sample and returned to Gordonvale near Cairns, where a special enclosure had been prepared for them.
By August the toads had successfully reproduced in captivity and 2400 were released in the Gordonvale area. Remarkably, no studies of the toad’s potential environmental impact had been carried out. Nor had the Bureau of Sugar Experiment Stations even determined whether the toad would actually eat the cane beetles.
Walter Froggatt, a prominent entomologist, was rightly concerned that the toads would become a significant pest.
“This great toad, immune from enemies, omnivorous in its habits, and breeding all the year round, may become as great a pest as the rabbit or cactus,” he wrote in 1936 in The Australian Naturalist, vol. 9.
Froggatt successfully lobbied the federal Health Department to ban further releases of the toad. However, the prime minister at the time, Joseph Lyons, succumbed to pressure from the Queensland government and the media to rescind the ban in 1936.
The toads thrived in the wild but had little or no impact on cane beetles, which are today controlled by chemical pesticides.
In 1950 the cane toad was declared a problem species. The poison the toad exudes kills many native predators, whose populations have since declined. They are also indiscriminate feeders that outcompete native species.
Cane toads have spread well beyond Queensland into coastal New South Wales, the Northern Territory’s Top End and the Kimberley region of Western Australia. They are now moving westward at an estimated 40–60km per year.
“There is unlikely to ever be a broadscale method available to control cane toads across Australia,” says the Australian government.
Today, research efforts are focusing on finding methods to protect the most vulnerable native species and on gaining a better understanding of how Australian wildlife is adapting to the toad’s presence.
‘Introduction of cane toads’ forms part of the National Museum of Australia’s Defining Moments in Australian History project.
