Without a doubt, the world’s wildlife need refuges, reserves and parks specifically set aside for habitat and protected from development and human incursion. In the U.S., National Parks and Wildlife Refuges serve this role capably.

But there are other, lesser-known publicly owned lands that play a crucial role in promoting the health and diversity of iconic species like wolves, grizzly bears and bald eagles—national forests and grasslands.

The groundwork

Often overlooked by many of us, America’s 193 million acres of national forests and grasslands provide critical habitat, migration corridors and other invaluable resources for our threatened and endangered wildlife. These important lands harbor more than 3,000 species of wildlife and 10,000 species of plants, including hundreds of threatened and endangered species. They also provide natural “bridges” that connect wildlife populations across regions and landscapes.

National forests help reduce the negative effects of “island populations,” or populations of wild species that are cut off from other isolated populations, which results in in-breeding, population declines, degraded habitat quality and reduced chance of long-term success. By ensuring that our national forests continue to provide high-quality habitat and opportunities for species’ expansion, we can help our wildlife not only survive, but succeed.

"National forests and grasslands harbor more than 3,000 species of wildlife and 10,000 species of plants, including hundreds of threatened and endangered species.

For example

Consider the Greater Yellowstone Ecosystem. Anchored by world-famous Yellowstone and Grand Teton National Parks, the Greater Yellowstone Ecosystem is a complex of public lands surrounding Yellowstone and Grand Teton Parks that includes five National Forests. These national forests provide habitat and travel routes for the Park’s growing populations of wolves and grizzly bears and for the plants and animals on which they depend, like elk and deer.

Wolves, reintroduced to Yellowstone National Park in the 1990s, have demonstrated the importance of National Forests in providing both habitat connectivity and additional home ranges for growing wildlife populations. As Yellowstone wolf populations grew following reintroduction, new packs split off and moved into adjacent National Forests that are part of the Greater Yellowstone Ecosystem. As packs became established in those lands, individual wolves continued moving into neighboring national forests, eventually reaching Glacier National Park in Northwestern Montana where they were able to mix with Canadian wolves, introducing important genetic diversity.

Following the tracks

Now, those wolves are establishing packs in national forests in Oregon and Washington, and biologists expect them in California’s national forests soon. Without the connectivity and additional habitat provided by National Forests, Yellowstone wolf populations would have remained in the Park, unable to grow beyond the Park’s carrying capacity. While Yellowstone provided the initial core habitat for wolves’ successful reintroduction, our national forests provided travel routes and new home ranges that help ensure the species’ long-term survival.

The next time you’re visiting a National Park and are lucky enough to catch a glimpse of an endangered species or threatened plant, consider the role that neighboring national forests play in promoting the health and vitality of the species you’re watching. Chances are, it has a close relative living nearby on a national forest.