Australia lacks large carnivores like lions and wolves, which has led to the assumption that marsupials like kangaroos and wallabies do not fear predators. However, a new study conducted by Western University biology professor Liana Zanette, along with collaborators from the University of Tasmania, shows that Australian marsupials fear humans more than any other predator. The study, published in the journal Proceedings of the Royal Society B, found that kangaroos, wallabies, and other marsupials were 2.4 times more likely to flee in response to human voices compared to other predators such as dogs, Tasmanian devils, or wolves.
The results of this study echo findings from similar studies conducted in North America, Europe, Africa, and Asia, which all show that wildlife worldwide perceive humans as the most frightening predator. Zanette and her team worked in the eucalypt forest in Tasmania, where they used hidden camera-speaker systems to film the responses of marsupials to different predator sounds. They found that every species in the marsupial community was roughly twice as likely to flee from humans as the next most frightening predator, which was dogs.
According to Zanette, the fear of humans demonstrated by wildlife can have dramatic ecological consequences, as fear itself can reduce wildlife numbers and cause cascading impacts on multiple species throughout entire landscapes. The study also found that humans are considered a “super predator” by global surveys because they kill prey at much higher rates than other predators. This perception of humans as a major predator is consistent with the profound fear of humans that is being revealed in wildlife worldwide.
The use of hidden camera-speaker systems allowed the researchers to trigger animal responses to different predator sounds, including humans speaking calmly, dogs barking, Tasmanian devils snarling, wolves howling, and non-threatening controls such as sheep bleating. The research showed that wildlife clearly recognize humans as the most dangerous predator, despite the widespread perception that large mammalian predators are the most fearsome. This “invisible killer” status of humans is underestimated by people, but it is evident that wildlife perceives humans as the most lethal predator.
Overall, the study provides important insights into the fear that wildlife have for humans and the implications it can have on ecosystems. By demonstrating that Australian marsupials fear humans more than any other predator, the research highlights the significant impact that human presence can have on wildlife behavior and populations. This recognition of humans as the most frightening predator aligns with global surveys that show humans as the most lethal predators, making it crucial for conservation efforts to consider the ecological consequences of human-wildlife interactions.
