WHO’S THE BOSS HERE?

Mr. Wohlleben, you work in the Eifel region between western Germany and Belgium. Have the wolves made it back to that area?

No, not yet. We have had wolves in Germany only since the year 2000, and they are slowly moving across the country from east to west. So far they have not reached the region along the border with Belgium and Luxembourg. That will certainly occur in the next few years, however. And I’m sure I’ll notice their presence long before I see the first one—because of the way the other animals react.

How does that work?

I can’t tell you precisely how it works, but the forest has its own form of silent communication. One of my colleagues farther east recently told me that he always knows when there are lynx in his territory. For example, his cat will refuse to leave the house. If there are wolves around, the deer alter their behavior—as the preferred animal of prey for the new predators, they are in the most peril. Therefore their lives undergo a dramatic change.

Can you elaborate on that?

It’s quite simple: As long as they have nothing to fear apart from human hunters, the deer tend to stay in the dense underbrush. They know that we bipeds are slow and have to rely on both our stealth and our eyes. Wolves, on the other hand, have an excellent sense of smell and actively pursue their prey. Thus hiding doesn’t do the deer much good in that case. So when wolves are around, the deer prefer open spaces where they can see the wolves coming and quickly dart away. That preference modifies the very face of the forest.

Are you saying a forest with wolves looks different from one that has no wolves?

That is, indeed, the case. There is an old proverb from Russia: “Where the wolf goes, the forest grows.” If the deer are forced to leave the grazing grounds they prefer and spend more time in forest clearings, they browse less on younger trees than they would in deeper cover. That creates better conditions for reforestation. This can even influence the course of streams and rivers, as has been observed in Yellowstone National Park [see page 18]: When streams have more trees growing along their banks because the deer have started to avoid those places that are harder to escape from, the flowing water does not erode the soil as quickly as it otherwise would because the tree roots hold it in place. In addition, the new trees at the river’s edge begin attracting beavers, and they, in turn, will start building dams. At the same time, the diversity of the plants in the forest increases: When deer no longer have easy access to plants they consider delicacies, such as fireweed, they must rely on other fare. Without the presence of wolves these plants get overgrazed, making way for other plants the deer dislike, like foxglove, which is poisonous and crowds out other species. Similarly, the chances of survival improve for raspberries, which have few thorns