The U.S. Fish and Wildlife Service has agreed to take a new look at how much habitat needs to be protected for the bull trout — in the latest Obama administration rollback of Bush administration reductions in the Endangered Species Act protections for fish and wildlife.

Based on the decision, a federal judge on Wednesday dismissed a lawsuit brought by environmental groups challenging cuts to critical habitat designation for the threatened fish. Bull trout numbers have dwindled due to logging, mining, grazing and dams.

Judge Robert Jones in Portland, Ore., cited an inspector general's report that the bull trout was one of 13 species whose protection was jeopardized by influence exerted by Bush administration appointee Julie MacDonald in the Department of Interior.

The ruling noted that the inspector general's report had found "illogical" policy choices under MacDonald, and that many Fish and Wildlife staff believed that as a result the bull trout critical habitat rule was not based on science.

"I hope this brings the end of corruption of the critical habitat process under Julie MacDonald, and I hope the Obama administration will do it based on science instead of politics," said Michael Garrity of Alliance for the Wild Rockies, a plaintiff in the case.

Critical habitat protections for bull trout conflict with logging, mining and grazing on national forests in Oregon, Washington, Idaho, Nevada and Montana. The protections have been a legal battleground since 2001, when the original lawsuit was filed to force Fish and Wildlife to designate critical habitat, a requirement of the Endangered Species Act.

The original proposal to protect 18,450 miles of streams and 532,700 acres of lakes was cut and amended over the years, until it stood in 2005 at 3,828 miles of stream, 143,218 acres of lakes and 985 miles of shoreline, prompting another lawsuit.

The judge gave Fish and Wildlife until the end of this year to come up with a proposal, and Sept. 30, 2010, for a final critical habitat designation. Until then the 2005 rule remains in force.

"We are already working on a revision to the critical habitat," said Fish and Wildlife spokeswoman Joan Jewett. "We intend to comply with the court's schedule."

Fish and Wildlife had long resisted the need to designate critical habitat for many species, a requirement of the Endangered Species Act, arguing that limited funding was better spent on making endangered species list decisions, but was forced to do so by lawsuits.

When the Bush administration took over in 2001, it rolled back protections for a number of species that conflicted with logging, mining, grazing, dams and oil and gas drilling. So far, the Obama administration has agreed to expand critical habitat for the lynx, and reconsider decisions on the northern spotted owl and sage grouse.