First published in The Sydney Morning Herald on August 2, 1947

"Everything about it - its very name - is vile. Its huge belly is always distended. The angry glitter in its eye revolting. It has legs but they do not raise its carcase above the mire. It has eyes but they do not welcome light - its bane. Its habitation is filthy. Its habits disgusting. Its colour dingy. Its breath foul."

Thus ran an old tirade against the toad, a giant variety of which, according to recent reports, is out of hand in Queensland and getting closer to New South Wales.

The giant American toad, Bufo Marinus, was introduced into Queensland from Hawaii in June, 1935, by the Bureau of Sugar Experimental Stations, with the object of assisting in the natural control of the greyback beetle pest which, in the grub stage, is responsible for the loss of thousands of tons of sugarcane every year.

This toad, which hails from Mexico, is truly a giant among toads. Specimens with a body length of nine inches and a mouth large enough to swallow small birds, have been captured in that country.

It has a rough skin studded with large pores. The colouration is variable, ranging through various shades of brown. Its underparts are a dingy white or yellow. Mature males have low, spiny tubercles on their back. When provoked they eject a milky poison from large glands in clusters forming the tubercles.

In the first year, 60,000 toadlets were liberated in suitable localities, adjacent to grub-infested cane areas, in the Cairns-Innisfail districts of North Queensland only, on account of restrictions imposed by the Commonwealth Government. Egg strings were also placed in streams and in water holes.

The first Australian-born generations commenced to reproduce in the early summer months. In the first year it was estimated that 1¾ million eggs were laid in captivity, and toads were recovered a mile away from the nearest point at which they had been liberated as toadlets. Individuals up to 5¼ inches in length were found.

After their feeding habits were studied and it was noted that they ate garden insect pests and cockroaches, restrictions were lifted, and in 1938 toadlets were introduced to all sugar areas in Queensland, where grubs caused noticeable injury. Prolific breeding followed, and the toads scattered far and wide. They were observed eating greyback beetles under natural conditions during beetle flight.

By 1939 it was considered that the toads had reached peak populations in areas where the original releases were made.

A systematic examination of the stomach contents of the toads was carried out to determine what constituted their food in their new habitat.

Apart from greyback beetles, there were found other cane pests, including the very important borer weavil.

The Bureau's report of 1940 pointed out, however, that on the score of observations in the field, and because grub damage had increased that year in areas where toad population was high, it was evident that the number of beetles destroyed by the toads was relatively small compared with the number that were nightly on the wing. Evidence seemed to indicate that the toad might be of more use in the destruction of the beetle borer.

Always seeking out the damp spots, the toads invaded household gardens and wood heaps, and in the wet areas of North Queensland are now to be seen almost everywhere.

The unexpected sight of one of these ugly amphibians is startling, but it usually makes off, seeming to run rather than hop.

Roads, where they pass close to tropical vegetation, are littered with the bodies of hundreds of these creatures, victims of passing motor cars.

Although their habits are nocturnal they cannot see in complete darkness and seem to be attracted by dim light. Around Innisfail at times they are seen in such numbers on the roads, near street lights, that the whole surface appears to be "alive."

There is no record of humans being affected by their poison, but dogs and cats suffer temporarily.

A dog catches the toad by the back, and although the dog's mouth is not in contact with the toad for more than an instant he immediately loses interest. He refuses water, and within a minute or so shows signs of general paralysis and weakness. He writhes and whines in pain, but after an interval of about 20 minutes is quieter and recovers completely without lasting effects.

A comprehensive series of experiments were carried out by the bureau to test the effect of possible contamination of domestic fowls' drinking water by toads bathing in it overnight and the feeding of young toads to poultry. The tests were severe, but no ill effects were noticeable. One fowl ate no fewer than 142 small toads in little more than an hour yet remained quite normal.

Toads have been observed feeding on small grasshoppers so it would appear that they will be useful in checking those pests.

Whether they will become pests themselves remains to be seen. Since the appearance of the toads in south Queensland, apiarists have asked the Department of Agriculture to keep them out of New South Wales be cause they fear they will develop an appetite for bees.

First published in The Sydney Morning Herald on August 2, 1947