Not all humans are equally frightening to wildlife, says new study | India News

BENGALURU: Humans are often described as the world’s ultimate “super-predators” — a species that hunts, traps and fishes on scales far greater than any other animal. Wildlife biologists have long argued that this makes us uniquely fearful of other species. But a new study led by researchers at the Center for Ecological Sciences (CES), part of the Indian Institute of Science (IISc), suggests that the picture is more complex.The study, published in the journal Ecology Letters, found that animals clearly react with fear to people who kill humans — such as hunters and fishermen — but less consistently to those who pose no direct threat, including tourists and researchers.“The short answer is: no, not always,” said Sean D’Souza, a PhD student at the Center for Ecological Sciences and lead author of the study, when asked if humans are always “too scary” for wildlife.The team conducted a large meta-analysis reviewing three decades of research across species and ecosystems. They examined how wild animals changed three key behaviors: foraging, alertness, and movement. These behaviors reflect day-to-day trade-offs. Time spent scanning for danger is not time spent feeding. Moving away from danger costs energy and may limit access to food or mates.Across studies, animals exposed to lethal humans—those who hunt or fish—are more alert and spend less time feeding. In other words, they behaved like a constant threat. In contrast, responses to non-lethal human presence were weak and widely varied.Perhaps the most surprising finding was that some passive human structures, such as roads and settlements, were associated with less alertness in certain animals. “In some cases, these areas can serve as perceived refuges,” D’Souza said. Many natural predators avoid humans. As a result, predatory species may feel safer near human activity than in wild areas where predators roam freely.Co-author Maria Thacker, professor at CES, added that roadsides and residential edges are often cleared of dense vegetation. This can make them attractive pastures for small animals. However, such areas have obvious risks, including vehicle collisions.Scientists broadly support what they call the “risk allocation hypothesis.” This idea suggests that animals adjust their behavior depending on how intense and predictable a threat is. When danger is high and consistent, animals are alert. When the risk is low or predictable, they may relax.The results go beyond individual animals. Fears and changes in feeding patterns can ripple through ecosystems. If prey species overgraze certain areas, plant growth may change. If predators change their movements to avoid humans, the number of prey may increase. Over time, such behavioral adjustments can alter the ecological balance.The research also touches on wildlife management. Co-author Karthik Shankar, a professor at CES, said that lethal control measures, such as limited killing, can influence animal behavior. In some cases, less lethal interventions can reduce the movement of wild animals into human-occupied areas more effectively than other methods currently used to manage conflicts.At the same time, researchers caution that much remains unknown. Future work should aim to link behavioral responses to species characteristics, past human exposures, predator communities and landscape characteristics, D’Souza said. Long-term and experimental studies will be needed to determine whether the animals are simply getting used to the presence of humans or are undergoing profound evolutionary changes.For now, the findings challenge a simple narrative. Humans can be powerful predators. But to wildlife, we’re not always equally scary – and sometimes, paradoxically, we can appear safer than the wild.