Rather than relying on warm, fuzzy feelings to protect animals, conservationists suggest appealing to something more reliable: greed.

By selling financial contracts pegged to species health, the government could create a market in the future of threatened animals, making their preservation literally valuable to investors.

“The incentive to conserve would increase as the likelihood of species survival decreases,” said Cornell University biologist James Mandel. “If a species declines, investors have a bunch of paper that’s now worthless.”

Mandel and the co-authors of the proposal, published in Frontiers of Ecology and the Environment, are not the first to put a price on nature. The U.S. government already pays developers to preserve habitat for some endangered animals, such as the red-cockaded woodpecker.

Those simple programs, however, don’t make full use of market powers, and are used only for endangered species. There’s little reason for developers — say, Wyoming farmers with pronghorn antelope on their land, or oil companies prospecting on polar bear habitat in Alaska — to protect species that are merely in trouble.

The U.S. Fish and Wildlife services lists 163 animal species as threatened. As habitat shrinks and human development expands, many of them will become officially endangered. With that categorization comes expensive recovery programs, costly lawsuits and halted projects. In this atmosphere, developers often hide evidence of endangered animals on their land — “shoot, shovel and shut up,” as the saying goes — instead of saving them.

Rather than waiting for situations to go critical, say Mandel’s team, conservationists could immediately use the money they’d eventually spend to make animal protection profitable and more effective.

“There’s not much the government can do until a species is listed, and then they spend intense amounts of money, as they should. A species essentially goes from worthless to worth a lot, ” said Mandel. “We’re looking for some way to ease the transition, to put a price on a species before it becomes listed, and prevent the need for last-minute recovery.”

“Acting late is always more costly than acting early,” said Josh Donlan, another study co-author and director of Advanced Conservation Strategies.

Under their plan, the government would determine the cost of protecting a species if it becomes endangered. That money would be set aside to fund contracts with payouts pegged to species health. The contracts would be sold to landowners and developers whose actions directly affect the animals, though the contracts could be freely re-sold.

Should animal numbers fall beneath a predetermined threshold, contracts would be voided, and money devoted to anticipated recovery programs. If the species thrives, investors would be rewarded, with profits growing in direct proportion to species health.

“If there’s a 99 percent chance that a species is going to survive,” said Mandel, “you could trade that like a high-ranking bond. You know it’s going to pay out.”

Many details would need to be worked out on a case-by-case basis. If priced too low, the contracts would represent an easy payoff for environmental destruction. And both the government and investors would need to be sure that, come animal-counting time, nobody cooked the scientific books.

But the basic premise, said Ray Victurine, director of the conservation finance program at the Wildlife Conservation Society, “makes a whole lot of sense.” Now it needs to be tested in the real world.

“If you put all the pieces together, it has the potential to work,” said Victurine, who was not involved in the study. “But it’s going to work in very specific circumstances that have to be identified.”

Victurine said the idea was well-received at a conference of the International Union for the Conservation of Nature, the world’s oldest environmental group, but that the audience didn’t quite grasp the details.

Their difficulty may stem from the tricky finances involved. After all, the contracts are better-known by another confusion-engendering name: derivatives.

But unlike mortgage and credit derivatives that have crippled America’s economy, said Mandel, these derivatives wouldn’t be sold and re-sold until their risks were hidden. Instead they take risk currently assumed by the government, who foot endangered species bills, and place it with people who actually control species fate.