'Toadzilla’: How is this record-breaking toad a threat to Australia’s ecosystem?

A record-breaking giant toad has been discovered in Conway National Park in Queensland, Australia.

Park ranger Kylee Gray was “shocked” to spot the huge cane toad during a patrol deep in the rainforest earlier this month.

Kylee and her colleagues caught the vast animal and brought it back to their office, where it weighed in at 2.7 kg, earning it the nickname Toadzilla.

Guinness World Records lists the largest toad at 2.65 kg, a 1991 record set by a Swedish pet.

Toadzilla has now been euthanised and its body donated to the Queensland Museum for research.

Why was Toadzilla euthanised?

Cane toads, also known as giant toads, are native to South and Central America. They were introduced to Australia from Hawaii in 1935 to control cane beetles and other pests, but their population exploded.

They are now considered an invasive ‘feral’ species, and have devastating impacts on Australia’s ecosystem. Toadzilla was therefore euthanised - the usual fate for the toads across Australia - due to its ‘ecological impact’.

With no natural predators, cane toads have become a threat to native Australian species, explains senior park ranger Barry Nolan.

“A female cane toad like potentially Toadzilla would lay up to 35,000 eggs [twice a year]. So their capacity to reproduce is quite staggering,” he continues. “And all parts of the cane toad’s breeding cycle are poisonous to Australian native species, so prevention is a big part of how we need to manage them.”

Canva | Cover Media via Reuters
The giant cane toad was found in Conway National Park. - Canva | Cover Media via Reuters

How many cane toads are there in Australia?

Cane toads now number over 200 million in Australia and have colonised much of the north of the country, where they’ve caused the decline of native species. They have also appeared in the Kimberley region of Western Australia - one of the country’s last biodiversity strongholds. They typically devastate local native predators by 90 per cent within a few months of arrival, according to WWF Australia.

Cane toads are toxic and have been known to poison animals that prey on them. They spread diseases, deplete native fauna and reduce prey populations for native insect-eating species.

While cane toads will eat anything they can swallow, they mostly live on a diet of insects. It was initially hoped cane toads would replace the need for pesticides. However, they have failed to control cane beetles, which feed on sugarcane crops.

The toxic toads can live between five to 15 years in the wild. As they evolve to be larger, they are capable of travelling and spreading further.