Toad-ally understandable: Unravelling the secrets of Cane Toad calls

Help us understand how Cane Toad calls differ across Australia and around the world. By studying these differences, we can learn more of how they have been able to spread so successfully!

Cane toads (Rhinella marina) are incredibly resilient amphibians. Originally from Latin America (the Guianas, Brazil, Colombia, Trinidad and Tobago, Ecuador, Peru, Bolivia, Venezuela and Surinam), they have become a well-travelled species —thanks to humans! Cane toads have been introduced to Puerto Rico and most Caribbean islands, Papua New Guinea, the Philippines, the Solomon Islands, USA (Hawaii and Florida), Taiwan, Fiji, Japan and Australia. Once they were introduced, they developed incredible strategies to colonise and thrive in new environments. Their invasion of Australia is a prime example: since their arrival, they have spread far and wide. But what makes them an invasion machine?

Cane Toad colonisation

Researchers have discovered that Cane Toads at the invasion front show amazing adaptations. They tend to move longer distances, are faster, and often have longer legs than their counterparts back home in South America. Remarkably, their reproductive strategies have also changed in their new environments; toads in the invasion front focus more on dispersing than in mating! These gradual changes have helped Cane Toads establish themselves with astonishing success, but their incredible resilience also poses a major threat to native species. The rapid spread of the toads can help us understand how these adaptations have been key to their success and inform future management strategies.

Cane Toad calls

One fascinating question that remains is how Cane Toad use their calls to achieve their success? Calls are essential for communication in frogs and toads, facilitating mate recognition, male-male interactions, and defence. These vocal signals can change depending on an individual's size, physiology, behaviour, and even the environment in which they are produced. Given this flexibility, we suspect Cane Toad calls may have accents that vary across regions in Australia and even differ from their American relatives! Understanding Cane Toad accents across continents and regions around the world would help …

Advertisement call of a Cane Toad male (Rhinella marina), Australia.

^{Audio & Copyright: Jodi Rowley.}

How you can help!

To unravel this mystery, we need your help! We are looking for recordings of Cane Toads from all over the world — complete, high-quality calls that will allow the FrogID team to analyse how their calls differ across locations. Thanks to you, we already have over 10,000 Cane Toad calls submitted to Australia’s FrogID project, the largest library of frog calls in the world! But I still need calls from other parts of the word too! Although, Cane Toad (Rhinella marina) calls are what we most need, we would also love to receive calls from the closely related Mesoamerican Cane Toad (Rhinella horribilis), which is known from the Guianas, Brazil, Colombia, Trinidad and Tobago, Ecuador, Peru, Bolivia, Venezuela and Surinam.

How do you record Toad calls in Australia? Please record calls on your smart phone using the Australian Museum’s free FrogID app.

How do you record Toad calls from other parts of the world?

Submit any recordings from elsewhere to the iNaturalist project “Cane Toads Worldwide”.

For a top-quality Cane Toad recording, you will need to be as close as you can to the bumpy singer. Record calls from start to finish, ideally from one individual or a small chorus. If you have any questions about my research, feel free to reach out. Together, we can uncover the secrets of these rough-skinned invaders!