extirpation and recovery | attitudes | ecological role | northeast habitat | genetics debate

Ecological Role

All animals play important roles in their natural environments, but there are some that determine basic ecological processes. The wolf is one, known among conservation scientists as a highly “interactive” species. As a top predator, the wolf regulates entire food chains, so both its presence and absence has cascading effects.

Wolves help to cull sick and weak deer, elk, and moose, keeping herds healthier and stronger. The proportion of young versus adults that wolves consume varies with the reproduction and survival of these animals—a pattern that regulates population levels. Wolves also keep herds and individuals vigilant and on the move, reducing the loss of vegetation and other problems (like soil erosion) that result from overgrazing. And because wolves require large areas to hunt and form new packs, maintaining sufficient habitat for wolves also means having enough habitat for a lot of other wildlife (the so-called "umbrella” effect).

Since wolves were reintroduced into Yellowstone National Park in 1995, scientists have had the chance to study how environments are influenced by the species. Studies indicate that elk herds have changed their grazing patterns, decreasing overgrazing and damage in riparian areas. In turn, this has contributed to the regeneration of vegetation and cottonwood, willow, and aspen trees; the cooling of streams shaded by the trees; and the return of trout, beaver, and other animals.

In-depth research on the particular effects of wolves on the Northeast’s environment is impossible without the animal present. However, lessons can be learned from other regions with similar natural conditions. For example, research in the Great Lakes region shows that the browsing of plants, shrubs, and seedlings by deer is less intense in areas where wolves are present—giving vegetation a greater chance of survival and growth. And in Ontario and Québec, officials recognize the important role that wolves play in maintaining the diversity of both wildlife and vegetation.