Minnesota and Midwestern moose will not be listed as a federally endangered species, a designation that would have bolstered a number of protections for the animals.

The state’s moose population, which has plunged by 60% since 2006, faces threats from disease, wolves, parasites and a warming climate. The decision Tuesday by the U.S. Fish and Wildlife Service puts to bed a petition that has been under review for five years.

“We’re disappointed in the ruling and we definitely disagree,” said Collette Adkins, a biologist and attorney for the Center for Biological Diversity, the group that petitioned to have the moose listed.

The Fish and Wildlife Service did not mention the health or status of Minnesota’s moose population or the threats it is facing in its ruling, but instead focused on whether or not there was a technical difference between moose in the state and those across the border in Canada, where population numbers have remained more robust.

Endangered species protections would have added another layer of scrutiny to any major development near moose habitat, requiring companies to review the effects on the animals.

“Now it’s going to be a lot harder to ensure that things like mines and other habitat-destroying projects don’t go forward without protections for moose in place,” Adkins said.

Nearly two-thirds of Minnesota’s moose population died off over the course of just a few years, falling from more than 8,000 animals in 2006 to fewer than 3,000 in 2013. The population has not recovered, but it also hasn’t gotten worse, holding stable at between 3,000 and 4,000 animals.

The Minnesota Department of Natural Resources (DNR) has listed the animal as a species of special concern for several years, and hasn’t allowed a moose hunting season in nearly a decade. While the Fish and Wildlife decision means that moose won’t gain any new federal protections, Minnesota regulations will remain.

The major threats to moose, especially the warming climate, are not going away anytime soon, said Bridget Henning-Randa, DNR endangered species coordinator.

“It will continue to be a species we’re concerned about and will monitor,” she said.

Lawmakers have prioritized funding from an environmental trust in recent years to speed up research into what caused the drop in moose numbers and how to start the recovery of one of the state’s most cherished animals. Researchers from the DNR, the University of Minnesota and other agencies and schools are trying to find ways to enhance or save habitats that may slow a slug that has been spreading a deadly parasitic brainworm, and examining whether unlikely factors, such as beavers, help moose avoid predation from wolves, among other projects.

Despite the loss of population in Minnesota, the Fish and Wildlife Service found that there was no significant distinction between the moose in the state and those of the same subspecies north of the Canadian border. Because the Minnesota moose are not discrete from those in Canada, either in biology or in the way the animals are managed, the subspecies “is not a listable entity,” it ruled.

The Center for Biological Diversity is deciding whether to appeal the decision or to file a new petition with more of a focus on the differences between U.S. and Canadian moose, Adkins said.

The petition would also have listed the moose as endangered in Wisconsin, North Dakota and Michigan’s Upper Peninsula. North Dakota’s Game and Fish Department, which oversees a moose hunting season, argued against the listing, saying numbers have been stable in the state for years without wolves or black bears to thin the herd. The Wisconsin and Michigan Departments of Natural Resources argued that the few moose hanging on in those states are more likely an eastern subspecies from Ontario than the northwestern subspecies found in Minnesota.