Fish was once found throughout the upper Missouri River drainage

MISSOULA (AP) -- The U.S. Fish and Wildlife Service has agreed to determine by April 2007 if the fluvial arctic grayling should be protected under the Endangered Species Act.

The agreement to settle a lawsuit filed by the Arizona-based Center for Biological Diversity also requires FWS to pay the group's attorney's fees -- $111,408. It was approved by U.S. District Judge John Bates in Washington, D.C. on Wednesday.

''The settlement agreement doesn't presuppose that the grayling will be listed," said Doug Peterson, a Fish and Wildlife Services fisheries biologist in Helena. ''We will go through the process of evaluating its status."

In May 2003, the center sued FWS, saying the agency hadn't done enough to protect the river-dwelling fish that has been reduced to a single, self-sustaining population in a stretch of the Big Hole River in southwestern Montana. The fish was once found throughout the upper Missouri River drainage.

''The Montana fluvial arctic grayling is on the brink of extinction," said Noah Greenwald, conservation biologist with the Center for Biological Diversity. ''The grayling needs the safety net of the Endangered Species Act -- our nation's most important environmental law -- to survive."

In 1994, FWS determined that listing the grayling was warranted, but precluded because there were other species with a higher priority. Since then, the grayling has been considered a ''candidate species" and its status has been reviewed by the agency on an annual basis.

Last year, the grayling's priority level was raised due to the ongoing drought, Peterson said.

The state Fish, Wildlife and Parks Department is working on a ''candidate conservation agreement with assurances" it hopes will eliminate the need to listing by encouraging landowners to protect streamside habitat and leave more water in the streams.

The state's restoration plan for fluvial Arctic grayling, developed in 1995, sets a strategy for establishing grayling populations in other areas.

Last year, the Natural Resource Conservation Service set aside $1 million to pay landowners to leave water in the river. Many area landowners have been voluntarily leaving water in the river for nearly 10 years, in an effort to stave off a listing.

The state has been stocking Ruby River with grayling, and there is some evidence of natural reproduction, but it's not a self-sustaining population yet, Peterson said.

The state has also made efforts to re-establish grayling in the Sun, lower Beaverhead, Madison, Gallatin and Jefferson rivers, he said.