When Alaskans think about economic activity on federal land, they probably think about oil drilling in places like the National Petroleum Reserve-Alaska.

They might not think about the economic impact of camping out for the night.

A new study focuses on the economic value of "quiet recreation" on lands overseen by the Bureau of Land Management throughout several states, including Alaska. It found that recreational activities like camping, hiking, hunting and fishing had a $47 million spending impact in 2014, the study found. That pencils out to $13 million generated in personal income tied to that recreation.

Pew Charitable Trusts commissioned the report from consulting firm ECONorthwest, which found that nonmotorized recreational activity on 246 million acres of BLM land supported 25,000 jobs and generated $2.8 billion overall for the U.S. economy in 2014.

Ken Rait, director of the U.S. public lands program at Pew Charitable Trusts, said the nonprofit commissioned the study because recreation on BLM lands is less examined than, say, development activities.

"We wanted to make sure that the economic value of these types of recreational uses is properly accounted for in how the agency considers its land management decisions," Rait said. "We know that there's a positive impact in local economies ... We just wanted to make sure this is part of that larger picture."

In 2014, Alaska saw more than 540,000 quiet recreation visits to the state's 87 million acres of BLM lands, according to the report. The study also found that 453 jobs in Alaska were supported as a result of these visits.

In the 12 U.S. states ECONorthwest studied, the number of visits that year topped 60 million, "nearly two-thirds of which were by people enjoying quiet (nonmotorized) recreation activities."