Our walks in the forest change the behavior of animals

With the sunny days, we enjoy going for walks in the forest, enjoying the freshness of the trees and admiring the spectacle of nature. But our walks are not without consequences for wildlife.

A team of American ecologists studied the impact of our walks in the forest on animals. An update on this work with Mathilde Fontez, editor-in-chief of the magazine Epsiloon.

franceinfo: When we take advantage of a forest, do we really change the behavior of the animals?

Mathilde Fontez: Yes, we had to suspect it, but until then, this had not been examined precisely: what is the impact on the fauna of our hikes, our mushroom picking, our mountain bike raids in the forest? Not because of the trash we leave behind, but by the noise we make, by our mere presence. It must be said that it is quite difficult to measure precisely. The researchers, for this first study, simply analyzed the impact of sound, of human noises. They worked with sound recordings in a Wyoming forest and with cameras to measure the animals’ movements and behaviors. We do not go unnoticed. Animals flee 3 to 4 times more than when we are not there. They adopt vigilant behaviors: they are on the lookout, they eat less. And the effect is lasting, since in the places we passed, the wildlife remains less numerous for several days in a row.

Is this the case for all animals?

The phenomenon is particularly marked for herbivores – elk for example –, less so for carnivores which are themselves predators, like us. These results are consistent with other studies which have multiplied in recent years on the impact of predators on ecosystems. The presence of a predator not only has a local effect, when it attacks, but also a global effect on the ecosystem. A single presence induces significant changes in prey, which therefore avoid certain territories or change their feeding mode. For example, off the coast of southern Africa, sea lions frighten Cape boobies to the point of causing them to migrate offshore at night, far from fish reserves.

Should we talk about “landscapes of fear”?

This is in fact the formula that attempts to capture this phenomenon: a gradient of dangerousness which is built in the minds of animals and which directs their behavior. A landscape of fear of which humans are a part, this is what this study confirms. It can be positive or negative on biodiversity: in wild forests for example, other studies have shown that predators tend to promote the biodiversity of flora, by preventing herbivores from always attacking plant species. which are their favorites.