Skip to main content

Expanding the Territory for Yellowstone’s Bison

Bison and calf in Yellowstone National Park's Lamar Valley.

Each spring, bison migrate across the park's western boundary to get to lower elevation foraging areas—including Horse Butte—that provide the earliest new grass each spring.

Photo courtesy of Jim Peaco / NPS

What’s at Stake

The Montana Stockgrowers Association and two other plaintiffs filed a lawsuit seeking to order the capture, hazing, or slaughter of bison in the Horse Butte area just outside the west boundary of Yellowstone National Park.

Overview

The Montana Stockgrowers Association and two other plaintiffs filed a state court lawsuit seeking to order the capture, hazing, or slaughter of bison (also known as buffalo) by a Montana state agency in the Horse Butte area just outside the west boundary of Yellowstone National Park.

In response to recent land management changes that have entirely eliminated cattle from Horse Butte, Montana has allowed more freedom of movement for bison that migrate into the Horse Butte area during the winter season.

Nevertheless, claiming a fear that bison will transmit a disease (brucellosis) to cattle, the stockgrowers and their allies asked a Montana court to order the state to continue to capture and kill bison under a plan that was developed when cattle still grazed on the butte.

Earthjustice intervened in this case on behalf of local landowners and conservation groups to stop the stockgrowers from reinstating a bison slaughter, and in 2010 the Montana court rejected the attempt to require the Montana Department of Livestock to haze, harass and slaughter all bison that cross the Yellowstone National Park boundary into the Horse Butte area.

Case ID

1792

Case Updates

May 22, 2009 | Video

Bison Harassment, Wounded Calf

A video clip shows a baby bison with a broken leg fleeing helicopters and mounted riders. The tragic scene took place in May 2009 on Horse Butte peninsula, as federal and state agents drove park buffalo off spring pastures because of perceived conflict with livestock.

May 20, 2009 | Video

Horse Butte Flyover: Migratory Path of Yellowstone Bison

This short video shows one of the migratory paths that Yellowstone bison take out of the park's western boundaries into the Gallatin National Forest. They end their journey at lower elevation at the Horse Butte peninsula. It is here the first grasses of spring grow and the bison have their calves.

The green and yellow lines mark the Yellowstone National Park and the Gallatin National Forest boundaries, respectively.