Federal ownership of land in the western United States has triggered conflicts for decades. On Saturday, a group of about 20 armed protesters occupied the headquarters of a National Wildlife Refuge in rural eastern Oregon, seeking return of federal lands to local ranchers and loggers.

The federal government manages these lands in an effort to balance environmental protection and conservation with permitted uses. In response, ranchers, private land owners, and some local and state governments have fought for more control over how the land is used. In some cases, this has led to high-profile protests like the one that erupted Saturday.

What is the Malheur National Wildlife Refuge?

The refuge in eastern Oregon was established in 1908 by President Theodore Roosevelt to protect waterfowl, such as ducks and ibises, many of which were being wiped out for the feather trade. According to the Audubon Society of Portland, the 188,000-acre refuge managed by the U.S. Fish and Wildlife Service "represents some of the most important bird habitat on the Pacific Flyway."

How much land in the American West does the federal government control?

The federal government owns 640 million acres, or nearly a third of the U.S. landmass. Much of that is found in the West, a remnant of the way the country expanded over time.

In the East, ten states have less than two percent of land controlled by the federal government. In contrast, 84.5 percent of land in Nevada is controlled by the feds. Oregon is 53.1 percent federal controlled. Idaho, Arizona, New Mexico, and California aren't far behind, and Utah is even higher at 57.4 percent.

What does the federal government do with this land?

This patchwork of federal lands is overseen by different agencies, mostly the National Park Service, the Bureau of Land Management (BLM), the Forest Service, and the Fish and Wildlife Service. Some of it is protected as wilderness or park land but much of it is used for grazing, logging, hunting, fishing, and other purposes. Land officially designated as a national park is given far more protection than land overseen by the Forest Service or Bureau of Land Management, which is often open to logging, mining, grazing, and other activities.

The nation has more than 560 wildlife refuges, which are set aside to benefit birds, fish, other animals, and their habitat. "Wildlife-dependent uses involving hunting, fishing, wildlife observation, photography, interpretation, and education, when compatible, are legitimate and appropriate uses of the Refuge System," according to the Fish and Wildlife Service.

Public Land's Big Footprint Federal lands comprise nearly one third of the U.S. land mass, a ratio that is even higher in the American West and Alaska. This cartogram uses squares to represent each state by its area, with the smaller green area within indicating the share of land that is publicly owned. The District of Columbia contains 12.8 square miles of federally owned land (21%) NG STAFFSOURCE: Congressional Research Service

Is there a long history of land conflicts in the West?

Debate over federal land policy has raged for centuries, often pitting conservationists against business interests and national interests against local ones. In the 1970s and 1980s a push for local control spread across much of the West, gaining the name Sagebrush Rebellion. Ronald Reagan was among the movement's supporters. Although he slowed down designation of new wilderness areas while in the White House, the movement did not lead to widespread change of land policy.

Who are the armed protesters in Oregon?

The leader of the group is a Nevada cattle rancher named Ammon Bundy, who is occupying the refuge with his brother Ryan and other supporters. The Bundys are sons of Cliven Bundy, a Nevada rancher who was embroiled in a high-profile standoff with the U.S. government last year.

Although the protesters have posted messages on Facebook claiming that as many as 100 people are at the refuge, local media who have toured the area say the actual number is closer to 20, with about a dozen pickup trucks parked there.

The government says the facility was closed and unoccupied when the protesters, armed with semiautomatic rifles, arrived.

What do the protesters want?

In Facebook messages, the protesters say they want the federal government to turn over management of lands to local control. Ryan Bundy told the AP that they would like to see more land used "for ranching, logging, mining and recreation" and free of federal oversight.

Protests started in Burns last week after ranchers Dwight and Steven Hammond were about to be sent back to jail for setting fires on land owned by the BLM, on which they leased grazing rights. Witnesses told the court the Hammonds intentionally set the fires after they poached deer, though the Hammonds had said they set fires to clear invasive species. Ryan Bundy called the Hammonds' case "an example of the terrorism that the federal government is placing upon the people."

A lawyer representing the Hammonds has claimed the protestors do not represent the views of the family.

This story was updated at 10:00 am January 5.