Editor's Note: One person was killed and eight were arrested on Jan. 26 as police cracked down on the nearly monthlong occupation. Protest leaders Ammon and Ryan Bundy were arrested at a traffic stop en route to a community meeting, according to the Oregonian, while spokesman Robert "LaVoy" Finicum was fatally shot in a confrontation with police.

About 10 members of the group remained at the wildlife refuge, where police set up checkpoints and asked holdouts to leave. Ammon Bundy issued a similar request through his lawyer, asking his followers to "please go home." A few heeded the advice, but four people occupied the refuge for another two weeks. Finally, after lengthy negotiations with the FBI, they surrendered peacefully on Feb. 11, bringing the standoff to an end.

The trial against the Bundy brothers and six co-defendants began on Sept. 7 in Portland, Oregon, with the start of jury selection.

On Jan. 2, armed militants took over the Malheur National Wildlife Refuge in Oregon. The move is a protest against "overreach" by the United States, according to the group's leaders, who say they hope the refuge "will be shut down forever."

Why would anyone want to shut down a wildlife refuge? Do they hate animals?

No, or at least that's not their stated purpose. The roots of this standoff are long and tangled, dating back to the early days of Mormonism and the 1862 Homestead Act. Much has already been reported about the protest's origins (see brief overview below), but what about the refuge and the wildlife living in it?

Why are the militants there?

The takeover is ostensibly about two local ranchers, Dwight and Steven Hammond, who were convicted of arson related to fires that spread onto public land in the early 2000s. The Hammonds say their largest fire in 2001 was meant to kill invasive plants, but authorities say they set it to cover up an illegal deer hunt.

The father and son each faced a minimum five-year sentence, but when they were sentenced in 2012, a U.S. district judge decided that was too harsh. He sentenced Dwight to three months and Steven to one year, which they served. Yet the U.S. Justice Department appealed the sentences, arguing it sets a bad precedent to go easy on life-threatening crimes like arson. The Hammonds were re-sentenced to five years, minus time served, and returned to prison this week.

Ammon BundyAmmon Bundy, center, speaks to reporters at the Malheur National Wildlife Refuge on Jan. 4. (Photo: Rob Kerr/Getty Images)

The story upset two sons of Nevada rancher Cliven Bundy, who drew national attention in 2014 for his standoff with the U.S. Bureau of Land Management (BLM) over grazing rights on federal land. Ammon and Ryan Bundy went to Oregon in hopes of rallying support for the Hammonds, and after a peaceful protest on Jan. 2, they led a group of militants in taking over buildings at the Malheur National Wildlife Refuge (MNWR). Due to the holidays, the refuge was empty at the time.

The Hammonds have said the Bundys don't represent them, however, and the militants — all of whom are reportedly from other counties or states — seem to have little local support. "The Hammonds have turned themselves in. It is time for you to leave our community," Harney County Sheriff David Ward said Monday. "Go home, be with your own families and end this peacefully."

Malheur National Wildlife RefugeA member of the militant group walks down a road at MNWR headquarters on Jan. 4. (Photo: Rob Kerr/Getty Images)

The militants don't plan to leave soon, though, saying they're ready to occupy MNWR "for years." And while they picked this Oregon refuge because of its relevance to the Hammonds, their grievances run deeper. This is the latest flap in a long dispute between Western ranchers and the U.S. over federal management of public lands, although many like-minded landowners are dubious about the Bundys' plan.

"I don't even know what 'occupying the refuge' means," Susan Hammond, Dwight's wife, tells PBS Newshour. "I hope they've got some warm clothes."

burrowing owlA burrowing owl endures the winter cold at Malheur National Wildlife Refuge. (Photo: Jim Maloney/FWS)

Why does the refuge matter?

Malheur National Wildlife Refuge exists mainly to protect birds and other native wildlife from hunters and habitat loss. Unchecked plume hunting had caused many North American bird populations to plummet by the 1880s, and after hunters discovered large flocks of birds nesting at Oregon's Malheur Lake, most of the area's egrets were wiped out by 1898. They still hadn't recovered a decade later, according to the U.S. Fish and Wildlife Service, prompting efforts to conserve the survivors.

Originally named Lake Malheur Reservation, MNWR was first protected in 1908 by President Theodore Roosevelt "as a preserve and breeding ground for native birds." It was the 19th of 51 wildlife refuges created by Roosevelt during his presidency, and at the time it was one of just six refuges located west of the Mississippi River.

greater sandhill craneMore than 200 pairs of greater sandhill cranes nest at MNWR each year. (Photo: Roger Baker/FWS)

MNWR now includes 187,757 acres of wildlife habitat in the Northern Great Basin, or about 293 square miles (760 square kilometers). It covers just 0.4 percent of the ecoregion's total area, but it's "a tremendously important source of wildlife habitat relative to other portions of the Northern Great Basin," the FWS explains. That's because it's a crucial stop on the Pacific Flyway, a migratory corridor for birds that runs along western North America from Arctic tundra to tropical beaches and mangroves. At least 1 billion birds use the flyway every year, and MNWR offers resting, breeding and nesting habitat for hundreds of migrating species.

The refuge, along with the nearby Silvies River floodplain, supports up to two-thirds of the Pacific Flyway's most at-risk waterfowl. MNWR itself also provides significant nesting habitat for waterbirds, hosting more than 20 percent of all greater sandhill cranes that nest in Oregon. It's home to high densities of certain passerine birds, too, as well as the largest population of bobolinks in the U.S. West.

Aside from birds, about 60 mammal species inhabit MNWR, including mule deer, pronghorn, elk, mountain lions, bobcats, black bears and river otters. At least 14 different species of bats have been identified at the refuge, along with beavers, marmots, porcupines and about two dozen other rodent species. Bird-watching and other nature recreation draws more than 100,000 annual visitors to MNWR, who contribute about $15 million to the local economy every year.

mule deerThere is no big game hunting at MNWR, so deer — like these mule deer bucks — abound. (Photo: Barbara Wheeler/FWS)

The militants probably won't have much impact on local wildlife, at least initially, since they may number as few as 15 people squatting in a handful of small buildings on a 188,000-acre refuge. Much will depend on how long they stay and what they do while there. So far, law enforcement is taking a wait-and-see approach, wary of violent clashes like those at anti-government standoffs in the 1990s.

The group says its goal is to return MNWR to local control, but it has offered few specifics on how that would happen. Bundy believes Roosevelt overstepped U.S. authority by protecting MNWR in the first place, so his long-range vision for the sanctuary seems unlikely to mimic such a big-picture endeavor.

Yet the late American author and scientist Rachel Carson, in describing the role of national wildlife refuges seven decades ago, leans closer to Roosevelt:

"Wild creatures, like men, must have a place to live," Carson wrote. "As civilization creates cities, builds highways, and drains marshes, it takes away, little by little, the land that is suitable for wildlife. And as their space for living dwindles, the wildlife populations themselves decline. Refuges resist this trend by saving some areas from encroachment, and by preserving in them, or restoring where necessary, the conditions that wild things need in order to live."

Editor's Note: This story was originally published in January 2016 and has been updated with new information.

Russell McLendon ( @russmclendon ) writes about humans and other wildlife.