A group of Montana tribes and conservation groups are urging Montana Governor Greg Gianforte to veto a pair of state bills that they say will undermine reintroduction efforts of wild bison to Montana.

The bills, HB 318 and HB 302, would restrict the bison’s status as a native wildlife species to just a few circumstances and allow individual counties to overrule decisions on bison conservation made by state wildlife managers, critics have pointed out.

The bison is the official land mammal of the United States. Montana lacks public-trust, year-round wild bison.

“Either house bill 302 or HB 318 would almost certainly prevent any restoration of public-trust wild bison in Montana, preempting economic opportunities in many rural counties, ignoring the desires and statutory privileges of most citizens of the state and nation, and disregarding a host of state and federal legal mandates and policies,” Jim Bailey, a wildlife biologist who heads the Montana Wild Bison Restoration Coalition, wrote in Mountain Journal.

HB 302 is heading to the governor’s desk after it passed in the Legislature two weeks ago, while HB 318 is almost certain to pass in the coming weeks. Gianforte has not indicated his position on the bills, but earlier this week scrapped the state’s bison management plan in an effort, he said, to protect ranching interests. That move drew criticism from Native lawmakers.

Gianforte received a written warning for violating a state hunting requirement in February when he trapped and killed a wolf near Yellowstone National Park without first taking a required trapper education course. On April 23, he signed a bill allowing private reimbursement for expenses by successful wolf trappers and hunters which opponents said constitutes on a bounty on the canines. Gianforte previously signed bills extending the wolf trapping season and allowing the use of snares to trap wolves.

Signatories on the letter urging a veto include representatives from the Blackfeet Nation, Fort Belknap Indian Community, Fort Peck Assiniboine and Sioux Tribes, the InterTribal Buffalo Council, Defenders of Wildlife, World Wildlife Fund, Montana Chapter of the Sierra Club, The Humane Society of the United States, Natural Resources Defense Council, Laurel East Animal Center, National Wildlife Federation, Greater Yellowstone Coalition, Wildlife Conservation Society, and National Parks Conservation Association.

Efforts for introducing a wild bison herd in Montana have focused on the Charles M. Russell National Wildlife Refuge, which contains 1.1 million acres along the Missouri River.

“Bison are beloved by Montanans and are among North America’s most iconic species,” Chamois Andersen, senior Rockies and Plains representative at Defenders of Wildlife, said in a statement. “These bills are detrimental to bison reintroduction efforts in the state, preventing the restoration of this native species to their natural habitat.”

Once numbering some 30 million, bison were hunted to near extinction by the late 1800s. Though saved from extinction and thought to number around 500,000 today, most bison are managed as private livestock and contain cattle genetics. Only about 0.1 percent of the historic population are managed for conservation in the U.S., Canada or Mexico.