Fear of humans as apex predators has landscape-scale impacts from mountain lions to mice

Suraci and colleagues extended the ecology-of-fear framework to whole communities, using playbacks of human voices across the Santa Cruz Mountains to test how fear of humans cascades through a food web. They found that the sound of humans suppressed the activity and movement of mountain lions and mesocarnivores, which in turn altered the behavior of smaller animals down to mice, demonstrating that human presence triggers a fear-driven trophic cascade. The study showed that the non-lethal effects of humans, perceived as the ultimate apex predator, ripple across multiple trophic levels and reshape the behavior and movement of entire communities. It built on earlier puma-specific work to reveal landscape-scale consequences of human fear. The paper is influential for showing that simply being feared, humans restructure ecosystems beyond their direct physical impacts.