Islands of Doom

Field biologists, with their stubbornly insistent focus on the minutiae of the living world, are unlikely people to be scaring the bejesus out of us.

But they were the first to see, beginning back in the 1970s, that populations of myriad species were declining and ecosystems were collapsing around the world. Tropical rainforests were falling to saw and torch. Ocean fish stocks were crashing. Coral reefs were dying. Elephants, rhinos, gorillas, tigers, and other “charismatic megafauna” were being slaughtered. Frogs everywhere were vanishing. The losses were occurring in oceans and on the highest peaks, in deserts and in rivers, in tropical rainforests and arctic tundra.

Responsibility for this biological meltdown sits squarely on the shoulders of 5.7 billion eating, manufacturing, warring, breeding, and real-estate-developing humans. According to a National Biological Service study released early in 1995, ecosystems covering half the area of the 48 contiguous states are endangered or threatened. The longleaf-pine ecosystem, which once covered more than 60 million acres from Virginia to Texas, remains only in tiny remnants, and of the 261 types of ecosystems in the United States, 58 have declined by 85 percent or more and 38 by 70 to 84 percent.

If the United States had completely ignored its public lands, it might simply be getting what it deserved. But that’s not the case. National parks and designated wilderness areas in this country make up the world’s finest nature-reserve system. When President Clinton signed the California Desert Protection Act into law in 1994, the acreage of federally designated wilderness carved out of our public lands soared to more than 100 million acres, nearly half of them outside Alaska. The acreage of the national park system jumped to almost 90 million, more than one-third in the Lower 48. That is much more than I thought we would ever protect when I enlisted in the wilderness wars a quarter century ago.

So how is it that we have lost so many species while we have protected so much?

The answer lies in the goals, arguments, and processes used to establish wilderness areas and national parks over the past century. The most successful were those based on what environmental historian Alfred Runte terms “monumentalism” (the inspirational scenic grandeur of the Grand Canyon and Yosemite Valley), on the idea of “worthless lands” (unsuitable for agriculture, mining, grazing, logging, and other productive uses: the glaciers of Mt. Rainier, the sheer cliffs of the Grand Canyon), on utilitarian considerations (the Adirondack Preserve in New York, set aside to protect the watershed for booming New York City), and, most common of all, on recreational values. The result is that wilderness areas tend to be spectacularly scenic, rugged enough to thwart resource exploitation (or simply lacking valuable timber and minerals altogether), and popular for nonmotorized recreation.

But that’s not necessarily what wildlife needs. As conservation biologists have discovered, species can’t be brought back from the brink of extinction one by one. Nature reserves have to protect entire ecosystems, guarding the flow and dance of evolution.

For insight, conservation biologists draw on an obscure corner of population biology called island biogeography. Over the years, oceanic islands that were once part of nearby continents invariably lose species of plants and animals that remain on their parent continents, a process sometimes called relaxation. The first species to vanish are the big ones–the tigers and elephants. The larger the island, the slower the rate at which species disappear. The farther an island is from the mainland, the more species it loses; the closer, the fewer. If an island is isolated, it loses more species than one in an archipelago.

In 1985 ecologist William Newmark looked at a map of the western United States and realized that its national parks were also islands. The smaller the park and the more isolated it was from other wildlands, the more species it had lost. The first to go had been the large, wide-ranging creatures: gray wolf, grizzly bear, wolverine. Relaxation had occurred, and was still occurring. Newmark predicted that all national parks would continue to lose species. Even a big protected area like Yellowstone isn’t large enough to maintain viable populations of the largest wide-ranging mammals.

While Newmark was applying island biogeography to national parks, Reed Noss and Larry Harris at the University of Florida were studying the state’s endangered panther and its threatened black bear, hoping to design nature reserves for these species that were more than outdoor museums. A small, isolated group of bears or panthers faces two threats. Because it has few members, inbreeding can lead to genetic defects. And a small population is more vulnerable to extinction (winking out, in ecological jargon) than a large one; if the animals are isolated, their habitat can’t be recolonized by nearby members of the species. But if habitats are connected so that animals can move between them–even if it’s just one horny adolescent every ten years–inbreeding is thwarted and a habitat can be recolonized.

Noss and Harris designed a nature-preserve system for Florida that consists of core reserves surrounded by buffer zones and linked by habitat corridors. Over the past decade this visionary application of conservation biology has been refined by the state of Florida, and now state agencies and The Nature Conservancy are using it to set priorities for land acquisition and protection of key areas. Once a pie-in-the-sky proposal, a conservation-biology-based reserve system is now the master plan for land protection in Florida.

Conservation biologists tell us that we must go beyond our current national park, wildlife refuge, and wilderness area systems, that we need large wilderness cores, buffer zones, and biological corridors. The cores would be managed to protect and restore native biological diversity and natural processes. Wilderness recreation is compatible with these areas as long as ecological considerations come first. Surrounding the cores would be buffer zones where increasing levels of compatible human activity would be allowed at an increasing distance from the center. Corridors would provide secure routes between cores, enabling wide-ranging plant and animal species to disperse and facilitating genetic exchange between populations.

In the northern Rockies, groups such as the Alliance for the Wild Rockies and the Greater Yellowstone Coalition have been working to turn fragmented wildlands into viable habitats. They reckon that if Yellowstone isn’t large enough to maintain healthy populations of grizzlies and wolverines, then we need to link the park with larger areas, perhaps even the vast wilderness areas of central Idaho, the Glacier National Park/Bob Marshall Wilderness complex in northern Montana, and on into Canada. These efforts have produced the most expansive ecosystem-based legislation ever proposed in the United States. The Northern Rockies Ecosystem Protection Act (NREPA) would designate 20 million acres of new wilderness areas and identify essential corridors between them. The bill, endorsed by the Sierra Club, currently has 45 co-sponsors. In late 1991 a small group of scientists and activists married conservation biology and conservation activism on the grandest and most visionary scale yet. The Wildlands Project has set itself the all-encompassing goal of designing science-based reserve networks that will protect and restore the ecological richness and native biodiversity of North America from Alaska to Panama.

At a time when legislators are handing out private rights to public lands like candy, such visions may seem like delusions. Congress is dominated by zealots who would tear down decades of conservation policy and open public lands to the exploiters Teddy Roosevelt fought almost a century ago. Lurching through the Contract with America checklist, Congress threatens wilderness in the Arctic National Wildlife Refuge, in the northern Rockies, and in the slickrock canyons of Utah. Even the national parks aren’t safe from legislators who know the price of everything and the value of nothing.

An understanding of conservation biology and a vision of ecologically designed wilderness cores, corridors, and buffer zones can help stop the war that is being waged on the environment. For one thing, conservation policies and arguments are strengthened by a grounding in sound science. And a big-picture view allows activists to see that they are not isolated, that their campaigns to protect local wildlands fit into a national, even continental, plan. By developing long-term proposals for wilderness, we say, “Here is our vision for what North America should look like. Civilization and wilderness can coexist. By acting responsibly, with respect for the land, we can become a better people.”

A management plan that treats Florida as an ecological whole, a federal bill that crosses state borders to protect wildlands throughout the northern Rockies, and a proposal that covers an entire continent wrest the terms of the debate away from those who would gladly plunder our natural heritage. Do we have the generosity of spirit, the greatness of heart, to share the land with other species? I think we do.

Reprinted from Sierra, Sept-Oct 1995.

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