The Book of Hope: A Survival Guide for Trying Times

by Jane Goodall

Jane then explained how the gray wolf was wiped out a hundred years ago throughout most of North America. In Yellowstone, with the wolves gone, the elk overgrazed the park and the ecosystem suffered. Mice and rabbits could not hide, as the underbrush was gone, and their numbers plummeted. Bees had fewer flowers to pollinate. Even grizzly bears did not have enough berries to eat to prepare for their hibernation. The wolves had kept the elk away from the riverbank where they were exposed and vulnerable to attack. Without the wolves, the elk spent more time by the river, and the hooves of the large herds eroded the riverbank and caused the rivers to get muddy. Fish stocks declined in the cloudy water, and beavers could not build dams because overgrazing destroyed so many young trees. Once reintroduced into the park, the wolves brought the elk population down from about seventeen thousand to a more sustainable four thousand. Scavenger species like coyotes, eagles, and ravens started thriving, as did the grizzlies. Even the elk were better off as their population stabilized at a healthier and more resilient size—they are no longer starving to death in the winter. For humans, the drinking water in the area around the park became cleaner and the tourism industry grew dramatically with the wolves back. I was beginning to see what Jane meant about the tapestry of life and the interconnection between all species.