They aren't your typical breed of environmentalist. High on their agenda, for instance, is a proposal to sell off Yellowstone National Park, geysers and all. The buyer might be a privately endowed trust, which would pledge to preserve the park, or even an entertainment company such as Walt Disney.
Advocates call it the ``new resource economics'' - an unusual blend of environmentalism and free-market philosophy. Free-market environmentalists argue that private interests protect the environment better than governments can. Although clearly outside the mainstream, the ideas are winning at least partial approval from some policymakers and analysts.
``I'd be happy to see Disney running Yellowstone - I'm convinced it would be a better place if they did,'' says Terry Anderson, a Montana State University economist and senior associate at the Political Economy Research Center (PERC), a think tank in Bozeman, Mont., specializing in new resource economics.
Mr. Anderson and other ``PERCies,'' as associates call themselves, gather regularly at this tiny mountain resort just down the road from Yellowstone. At a recent conference for journalists here, the group spent hours debating the potential for privatizing everything from water rights to elk herds.
Richard Stroup, a PERC co-founder, says: ``Governmental control, without the responsibility of private property rights, has led over and over again to environmental destruction.''
An example of this, he says, is the Forest Service's logging program. In some parts of the country, the Forest Service spends more to build roads and provide other services for logging operations than it gets back in revenue. The reasoning behind this is that logging provides jobs for local communities, and therefore has benefits beyond immediate cash returns.
But free-market advocates contend that the problem is largely bureaucratic: Forest budgets are based on the volume of timber harvested, so there's an incentive to maximize cutting.
``With private property rights, both the owners and the users look for better ways to make use of their resources,'' says Mr. Stroup. And this, in turn, benefits the environment.
Free-market environmentalists point to several examples of how their philosophy is being applied. North Maine Woods Inc., for example, is a huge private preserve which supports itself by charging hunting and logging fees.
In Montana, the Pine Butte Preserve, owned by the Nature Conservancy, makes money by running a guest ranch and selling hunting and grazing permits. And the Audubon Society's Rainey Preserve in Louisiana earns money from oil and gas drilling.
But even advocates admit that many environmental problems don't lend themselves to free-market solutions. In the case of air pollution, for example, PERC representatives say they've yet to develop a market-oriented solution.
Meanwhile, private ownership of such things as parks and rivers is anathema to many who believe natural resources are a public heritage.
Free-market environmentalists argue that most parks, for example, could be made self-supporting merely by raising entry fees. But critics complain that this would cut off access to the poor.
``These guys have a lot to say about pricing timber,'' says Peter Emerson, an economist with the Wilderness Society in Washington. ``The trouble is that they don't have anything to offer for those things that don't have readily apparent markets.''
Mr. Emerson is part of a small but growing band of mainstream environmentalists who openly associate themselves with free-market solutions - up to a point.
Emerson argues, for instance, that ownership of forests and parks should stay in the hands of government. It's the organizational structure of agencies, he says, that needs to be changed to be made more sensitive to economic forces.
Much of the support for the new resource economics comes from groups that traditionally favor private-sector solutions. The Heritage Foundation, a conservative Washington think tank, even published its own report on free-market strategies for protecting the environment. But it is among environmentalists that the group sees the most potential for enlarging its influence.
``They're definitely building bridges to the environmentalists,'' says Doug Bandow, a senior fellow at the Cato Institute, a libertarian think tank. ``The first step, however, is convincing the environmentalists that not all free-market people want to pave over Yellowstone or bury toxic waste in Yosemite.''
A number of environmental groups, including the Environmental Defense Fund and the Wilderness Society, are beginning to integrate economics into their programs.
``The key is to make nature pay its way,'' says Anderson.