FILE - In this Sept. 6, 2013, file photo, Ingrid Forsmark kayaks on Kintla Lake in Glacier National Park, Mont. The Interior Department plans to cancel a long-suspended oil and gas drilling lease near Glacier National Park that's on land considered sacred to the Blackfoot tribes of the U.S. and Canada, according to court documents filed Monday, Nov. 23, 2015. (AP Photo/Matt Volz, File)

BILLINGS, Mont. | Members of Congress from eleven states say they’re concerned about postponements to recent oil and gas lease sales.

FILE - In this Sept. 6, 2013, file photo, Ingrid Forsmark kayaks on Kintla Lake in Glacier National Park, Mont. The Interior Department plans to cancel a long-suspended oil and gas drilling lease near Glacier National Park that's on land considered sacred to the Blackfoot tribes of the U.S. and Canada, according to court documents filed Monday, Nov. 23, 2015. (AP Photo/Matt Volz, File)

The lawmakers wrote U.S. Interior Department Assistant Secretary Janice Schneider asking her to explain the delays by Jan. 5.

They cited postponed sales on public lands in Arkansas, Utah and Michigan.

The effort is led by two Utah House Republicans — Natural Resources Committee Chairman Rob Bishop and Oversight Committee Chairman Jason Chaffetz.

Acreage leased by Interior’s Bureau of Land Management has dropped sharply over the past eight years. More than 4 million acres were leased in 2007, compared to 1.2 million acres in 2014.

Much of the decline has been attributed to efforts to ensure a ground-dwelling bird, the greater sage grouse, is not imperiled by drilling.