Enlarge By Mary Sage, Joseph Napaatug Sage via AP A polar bear watches a whaling crew near Barrow, Alaska, on Monday.    Enlarge 1996 file photo, AP About 2,200 manatees, which can weigh up to 2,000 pounds, remain in Florida.

Environmental groups have used it to halt development in pristine lands across the nation. Today, the law designed to protect animals such as the manatee from extinction also has become a legal tool of property-rights groups and developers.

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In a counterpunch to environmentalists who have filed lawsuits aimed at protecting hundreds of plant and animal species by listing them as endangered or threatened, property-rights groups such as the Pacific Legal Foundation are filing lawsuits to have animals and plants removed from the list so that development can proceed.

Meanwhile, industry groups have filed dozens of legal challenges aimed at allowing development on lands set aside by the U.S. government to help protect endangered species.

"The conventional wisdom is that environmental groups exclusively used this provision in court, but today, the industry lawsuits challenging critical habitat designations far outnumber environmental challenges," says Pat Parenteau, a law professor at Vermont Law School in South Royalton, Vt.

In a study he published last August on active litigation involving the Endangered Species Act, Parenteau counted 45 lawsuits filed by industry groups and five filed by environmental groups.

Litigating the list

At the forefront of the movement is the National Association of Home Builders, which recently prevailed in a legal battle over Arizona land that had been designated as a habitat for the cactus ferruginous pygmy owl. Two environmental groups have sued to restore the designation, and a court hearing on the issue is scheduled for Friday.

Likewise, the conservative Pacific Legal Foundation, based in Sacramento, is pressing the federal government to re-examine several animals and plants on the endangered list.

Both groups have found a relatively friendly audience in the Bush administration, which in recent years has loosened many of the restrictions in the Endangered Species Act. Among other things, the administration has focused on giving private property owners incentives to protect vulnerable species, rather than banning activity on such land.

"We've had property owners coming to us for years," says Rob Rivett, chief attorney for the foundation. "Finally, it became clear we didn't have any choice but to try to balance the scales."

The foundation, backed by contributions from foundations of the conservative Pittsburgh billionaire Richard Mellon Scaife, began filing lawsuits in the late 1990s, Rivett says. It is involved in more than 30 active suits across the USA.

Last September, the foundation reached a settlement with the U.S. government in a lawsuit brought on behalf of the California Cattlemen's Association, which wanted a review of the 194 plants and animals listed as endangered or threatened. Under the settlement, a review of 10 species must be completed by 2011, Rivett says.

The Endangered Species Act requires such reviews every five years, but the U.S. Fish and Wildlife Service lags far behind, says Renne Lohoefener, assistant director for the Endangered Species Act at the Fish and Wildlife Service.

"We simply never had the resources in terms of people and money," he says. "As a result, we are way behind in doing them."

New front in Florida

The foundation is now representing the Florida Home Builders Association in a similar lawsuit filed last November in federal court in Orlando. The lawsuit seeks to have the status of 106 plants and animals in Florida reviewed.

The Pacific Legal Foundation also is challenging the endangered status of:

• Four salmon in four western states, accusing the government of counting only natural population to determine listings, and not counting hatchery salmon. The suit potentially could ease restrictions on development and activities around rivers and streams in Oregon, Washington, Idaho and California .

• About 20,000 marbled murrelet birds in Coos County, Ore. County commissioners hope that delisting the bird would lead to more logging.

The Endangered Species Act has prompted litigation from the moment President Nixon signed it 33 years ago.

"There are more lawsuits now than there were 20 years ago because there are more species declining and more habitats being lost than there were 20 years ago," says Bill Snape, chief counsel for the Defenders of Wildlife in Washington, D.C.

There are 1,311 animals and plants listed as "endangered" or "threatened," according to Claire Cassel of the U.S. Fish and Wildlife Service. In 1986, there were 422 listed, she says.

Mike Mittelholzer, a vice president at the home builders association, says his organization's legal challenges are in response to lawsuits filed by environmentalists.

A bill passed last year by the U.S. House of Representatives would eliminate critical habitat protections — and essentially eliminate litigation.

Most of the legal battles over the Endangered Species Act are taking place in rapidly growing urban areas in the South and West.

In the Tucson fight over the cactus ferruginous pygmy owl, The National Association of Home Builders objected to the government's plan to set aside 1.2 million acres for the animal and fought to have it removed from the endangered species list. Last month, the Bush administration announced it would take the owl off the list.

That decision prompted two environmental groups to sue in Tucson federal court to block the delisting, says Kieran Suckling, policy director for Center for Biological Diversity.