Back in 1935, 102 cane toads were imported from Hawaii to Queensland. Sugar cane is an important crop here and the toads were brought in to control the cane beetle, an agricultural pest. The toads weren’t so keen on the beetles, which lived too high up for them to reach, but they liked Australia a lot. Today, it’s estimated that there are 200 million of them: they’ve spread south into New South Wales, west to the Northern Territory and are set to enter Western Australia any day now.
Numerous eradication solutions have been proposed including, infamously, death by golf club. One interesting idea involves breeding the toads to extinction, by releasing genetically-modified toads that produce only male offspring. You can read all about it in this article from the IMB.
It would be a slow process – the toad life cycle is seven years – and I’d like to see some population modelling studies that indicate the number of toads and time required for the gene to spread through the population. It’s an interesting idea though and you might argue, a good example of environmental benefit from the use of GMOs. Bludgeoning them might be fun (for some people) but it’s hardly an effective strategy for 200 million toads. It’s also important to identify them correctly and kill them humanely. They’re serious pests but it’s not their fault – they’re just creatures, doing their thing.