The Bush administration has repeatedly ignored the economic benefits of protecting endangered species habitat, using faulty accounting to create a false dichotomy between prosperity and conservation, a new report from environmental groups charges.

While critical habitat — land protected from any development that could compromise its ability to support endangered species — is initially designated by biologists without regard to economic consequences, the Interior Department has authority under the Endangered Species Act to exclude some areas if it determines that the cost of protecting them is excessive.

The environmental groups say Interior has abused that power in order to open intact habitats that endangered species need — and people could profitably use — to mining, commercial development, logging and mineral drilling.

The groups demand that, when Interior officials weigh making exclusions, they should give greater credence to the economic benefits of intact ecosystems, which include human recreation activities such as wildlife watching, hunting and fishing, as well as “ecosystem services,” natural functions such as water purification or carbon capture.

“The critical habitat piece has gotten one-sided in terms of economics,” said Dominic DellaSala, executive director at the National Center for Conservation Science and Policy, which contributed to the report. “They’re only looking at the costs of critical habitat, not the benefits of intact ecosystems — they’re only looking at what’s being spent and not what’s being saved.”

This miscalculation is far from innocent, said Chris Frissell, director of science and conservation programs for the Pacific Rivers Council, a conservation group that spearheaded the report.

“This is a way [the Bush administration] can manipulate the Endangered Species Act in the interests of special interests such as real estate firms, timber companies and power utilities,” said Frissell, speaking for his organization and not as a representative of all the groups involved in the report. “I think there’s no question this is part of a broad slate of actions designed to blunt the act’s impact.”

Frissell said there is currently a tug-of-war between agency biologists working to create adequate recovery plans and administration appointees working to protect industry development.

Interior officials with the U.S. Fish and Wildlife Service, which handles the critical habitat designations, declined to comment for this story.

The report focused on the bull trout and Californian red-legged frog, for which critical habitat designations were overturned after a federal investigation revealed that Interior appointee Julie MacDonald had exerted political pressure on FWS biologists to change their habitat recommendations (Land Letter, Sept. 18).

The report recommended that biologists and economists confer during the habitat designation process to enhance the latter’s understanding of conservation’s economic benefits.

It also recommended amending the critical habitat process to allow biologists to review economic exclusions to ensure the final plan is adequate to support species recovery. Currently, cuts made by Interior are final.