Researchers from the University of Tasmania and Western University have conducted experiments to show that Australian marsupials such as kangaroos and wallabies are most afraid of human “super predators,” fleeing from them 2.4 times more frequently than from other predators.
Recent experiments have demonstrated that carnivores and ungulates from Africa, Asia, Europe, and North America fear human “superpredators” much more than they do other predators. Australian mammals have been the focus of research into predator ignorance because they are suspected of exhibiting atypical responses. To experimentally test whether Australian mammals are also most afraid of humans, McGann others quantified responses of four native marsupials (eastern grey kangaroo, Bennett’s wallaby, Tasmanian pademelon, and brushtail possum) and taught fallow deer to playback predator (human, dog, Tasmanian devil, wolf) or non-predator control (sheep) vocalizations. Image courtesy of Pen_ash.
There is a widespread fear of humans among wildlife in Africa, Asia, Europe, and North America, reflecting the reality that humans are “super-predators,” far more dangerous than other predators worldwide.
Australian marsupials have been traditionally seen as naive to predators, based on their reactions to non-human threats.
“Our results significantly contribute to the growing body of experimental proof that wildlife globally view humans as the most feared predators on the planet,” stated Professor Liana Zanetto of Western University, a co-senior author of the study published in the journal Nature Proceedings of the Royal Society B.
“The strong fear of humans found in this study, as well as in similar recent experiments, is expected to have significant ecological repercussions, as additional research indicates that fear itself can reduce wildlife populations and that fear of humans can lead to cascading effects on multiple species across entire regions.”
To conduct their study, Professor Zanette and colleagues designed a hidden automated camera-speaker system in a sheep pasture in central Tasmania known as the Bowfront.
The five species they observed (eastern grey kangaroo, Bennett’s wallaby, Tasmanian pademelon, brushtail possum, and fallow deer) are the most prevalent native herbivores in the area.
As the animals came close (about 10 meters, 30 feet), the cameras captured their responses to non-threatening stimuli such as calm human speech, a barking dog, growling Tasmanian devil, howling wolf, or bleating sheep.
Native marsupials reacted by fleeing more frequently when exposed to the sound of their next most feared predator (dogs) compared to human voices, and were over twice (2.4 times) more likely to flee from humans (44.3% vs. 18.6% of trials).
These findings present conservation challenges but also offer insights for managing native marsupials in regions where they are overpopulated.
“Global studies have shown that humans kill prey at a much higher rate than other predators, making us ‘super-predators,’ and the intense fear of our presence in all wildlife species aligns perfectly with our inherent deadliness,” noted Professor Zanette.
“Humans are the ‘invisible killer.’ We may not perceive ourselves as the primary predator, let alone the most dangerous, but wild animals clearly see us for what we truly are.”
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Catherine McGann et al. 2024. Fear of human “super-predators” in Australia’s native marsupials and invasive deer. Proceedings of the Royal Society B 291 (2023): 20232849; doi: 10.1098/rspb.2023.2849
Source: www.sci.news
