Group files suit on Yellowstone roads

WASHINGTON, Dec. 16 (UPI) -- An environmental group said it filed suit Thursday in Washington to stop road improvements in Yellowstone National Park that lead bison to leave the area.

The coalition -- The Fund for Animals, the Bluewater Network and others -- said the grooming of snow-packed roads with the start of snowmobile season by the National Park Service is a "one-two punch" for the bison herds.

The herds leave the park by the improved roads and are slaughtered once outside the park, the coalition said.

"It is time for NPS to stop leading Yellowstone bison to their slaughter, by grooming the very trails that help bison find their way out of the park each winter," Michael Markarian, president of The Fund for Animals, said in a statement.

A federal district court judge found a year ago the NPS was ignoring "studies indicating that winter park use, and especially trail grooming, has lead to major changes in bison migration patterns," but NPS has failed to close a single road, the coalition said.