CANYONS OF THE ANCIENTS NATIONAL MONUMENT, Colo. — Linda Farnsworth picked her way across a field of loose rocks, down a steep slope under the overhang of sandstone cliffs. The archeologist stopped at the remains of a low stone retaining wall and searched briefly until she found the series of backfilled holes -- where looters had rooted around a remote kiva site for highly prized black and white Anasazi pots, tools and other prehistoric objects.
There are no signs or trails that lead visitors here, to Woods Canyon Pueblo, a site containing the remnants of 50 stone kivas, 220 rooms and 16 towers. But isolation offered scant protection when thieves swept through it a few months ago, leaving behind crude excavations, discarded pot shards and their own trash -- crumpled water bottles and wrappers from banana LifeSavers.
Although Farnsworth and other officials of the U.S. Bureau of Land Management, which oversees the monument, suspect that the looters scored a valuable haul from the site, they can't back up their hunch.
"I have no idea," said Farnsworth, the BLM's sole archeologist at Canyons of the Ancients, in Colorado's southwest corner.
Farnsworth and other officials can't say what's missing because they know so little about what was there. Only about 18% of Canyons of the Ancients has been inventoried to assess historic, cultural or scientific values. That's more than the BLM knows about a great many of the places it administers. Less than 6% of the 262 million acres managed by the agency has been inventoried for cultural resources.
Although about 263,000 cultural properties have been documented, some archeologists calculate there are more than 4 million sites across the BLM's lands in the West.
With 100 archeological sites per square mile, Canyons of the Ancients is regarded as the richest trove in an area famous for its remnants of American prehistory -- the Four Corners region of Utah, Arizona, Colorado and New Mexico. Yet Canyons of the Ancients has only one law enforcement officer to police the monument's 250 square miles.
At many federally managed cultural sites, damage is widespread, from casual pilfering by arrowhead collectors to excavating by professional thieves. Some haul power tools into canyons to cut out rock art panels. In a 2003 study of cultural and fossil resources on public land, the BLM reported that "increasing visitation to public lands is resulting in both intentional and inadvertent damage to these resources from collection, vandalism, surface disturbance.... Remote areas, once protected by their distance from populated areas, are now within easy reach of the hardy and well-equipped hiker, off-highway-vehicle user, and urban and suburban resident."
A study released this summer by the National Trust for Historic Preservation reached much the same conclusion and added that the BLM was too cash-strapped and understaffed to meet the challenge.
The report said that the BLM was failing to protect places with the most significant archeological and scientific holdings, such as Canyons of the Ancients, that are part of the National Landscape Conservation System. Created by former Interior Secretary Bruce Babbitt in 2000, the system encompasses national monuments, historic trails, rivers and wilderness areas.
According to the report, the most vulnerable sites include:
* Nine Mile Canyon near Price, Utah, which contains more than 10,000 Native American petroglyphs. Oil and gas leasing could bring as many as 2,000 new well sites to the area, with access to remote sites from new roads posing the biggest threat.
* Gold Butte near fast-growing Las Vegas, where a 10,000-year-old Native American settlement site has experienced a 366% increase in damage in the last year, including trash dumping, graffiti and bullet holes in petroglyph panels.
* Agua Fria National Monument about 40 miles north of Phoenix. The area's low mountains contain hundreds of pueblo sites, stone forts and rock art. A tenfold increase in off-road-vehicle use in the last five years threatens some structures.
The report by the National Trust highlights the disparity in funding between the two land management agencies within the Interior Department: the BLM and the National Park Service. The park service administers Mesa Verde National Park, about 20 miles southeast of Canyons of the Ancients. There, funding averages about $19 an acre. In contrast, Canyons of the Ancients operates at $2.27 an acre, though it is three times larger than Mesa Verde.
According to monument manager LouAnn Jacobson, more than 30% of Canyons' budget is funded through grants or gifts.
The National Trust report notes that in 2004 the park service spent $74 million on cultural resource management, though the BLM's 2006 budget for the same kind of work is $15 million. Recently, the Bush administration recommended a $5-million cut to the budget of the BLM's National Landscape Conservation System.