Cane toad invasion causes ecological crisis in Australia

An ecological crisis in Australia, stemming from the introduction of cane toads, has entered its 90th year. In 1935, entomologist Reginald Mungomery introduced cane toads from Hawaii to Queensland to combat the greyback cane beetle, a pest damaging sugarcane crops. However, the biological control failed as the toads did not effectively consume the beetles, which often reside higher on the stalks at night.

Since their release, the population has exploded from a small initial group to an estimated 200 million individuals, covering over 1.2 million square kilometers. The invasion has spread from Queensland to the Northern Territory and the Kimberley region of Western Australia, with the expansion rate accelerating significantly in recent years. Researchers have noted physical adaptations in the leading edge of the population, including longer legs and changes in skull morphology.

The toads have caused severe damage to local ecosystems due to their potent toxins. Native predators, including crocodiles, monitor lizards, and freshwater turtles, have suffered population declines of over 90% in certain areas like Kakadu National Park. Additionally, the toads prey on the eggs and chicks of rainbow bee-eaters, leading to reproductive failures in those species.