No human lives have been lost as a result of the fire that was deliberately set May 4 by Park Service officials to burn off accumulated dry wood and debris in Bandelier National Monument in hopes of preventing a catastrophic blaze set off by lightning. But as high winds and low humidity contributed to driving the fire out of control, more than 400 housing units were destroyed in the town of Los Alamos. About 11,000 residents had to be evacuated.

The flames also swept over the nearby nuclear weapons laboratory, where four of five historic structures used in the Manhattan Project’s assembly of the original atomic bomb during World War II were consumed.

Officials said that as of May 16, the outbreak had been 28 percent contained. However, more than 1,260 firefighters were still battling the blaze, which had raged through at least 44,323 acres and was threatening the 50,000-acre Santa Clara Pueblo. The Indian reservation has about 1,500 residents and a collection of ancient dwellings believed to have been built 800 years ago.

Preliminary results of a government investigation into the circumstances of the outbreak were due to be released on Thursday. Pending that probe by state, local, and federal representatives, U.S. Interior Secretary Bruce Babbitt and Agriculture Secretary Dan Glickman on May 12 suspended for 30 days the practice of prescribed burns. The temporary ban extended to 11 western states.

CONGRESSIONAL INVESTIGATION LIKELY

The incident seems likely to trigger a wide-ranging debate over the practice of periodically igniting small fires in order to prevent bigger outbreaks. Pete Domenici, the U.S. senator from New Mexico , along with other members of the state’s congressional delegation, have called for hearings. Domenici has requested a thorough investigation by the General Accounting Office, the U.S. Congress’ watchdog agency. Domenici wants the GAO to look into the details of this particular blaze, as well as to review the government’s whole prescribed burn policy.

The idea of setting small fires in order to prevent big ones has been around for roughly a century, and has been federal government policy since 1968. Foresters realized that the previous practice of suppressing all wildfires was actually hurting the natural balance of wilderness areas. Not only were forests accustomed to periodic pruning by wildfires being allowed to thicken, but many species of plants and animals that over eons have adapted to living with fire were being disrupted.

“I would think that if you walked through the Los Alamos area five or ten years from now, it will be so much improved,” said Forest Service fire effects specialist Dennis Simmerman. As disastrous as the fire has been for humans, Simmerman said, “You’ll soon have much improved vegetation for wildlife to use for cover and forage. The underbrush was very dense, hard for wildlife to penetrate. It will be more park-like, with openings and better visibility.”

Recalling a venerable American fire-prevention icon, Simmerman added, “The Smokey the Bear syndrome has been around for 80 or 90 years, saying that we don’t want fire in the forest. But Mother Nature has a different way of doing things. We need fire periodically just as a cleanup mechanism.”

Simmerman’s employer, the U.S. Forest Service Fire Sciences Laboratory in Missoula, Montana, has developed a database covering the effects of fire on about 1,000 plant and animal species on the North American continent.

THRIVING ON FIRE

The entries, based on a wide range of scientific literature collected since 1986, contain striking examples of how many species depend on fire to maintain their habitats and create new food sources. Although some animals inevitably are trapped and killed by fires, many more benefit.

One study found that the moose population on Lake Superior’s Isle Royale more than quadrupled in the decade following a 1936 fire that burned 26,000 acres. The University of Minnesota’s Laurtis W. Krefting concluded that “fire is the primary agent for maintaining the secondary successional vegetation that moose prefer.”

Paradoxically, the suppression of fire has led to a dramatic reduction in the nation’s grasslands, along with the animals that once lived there, according to Arizona State University biologist David E. Brown.

“It’s an international phenomenon,” said Brown. “When they’re not maintained by fire, grasslands become invaded by shrubby species—-plants or trees. Grassland species like bison, elk, and pronghorn antelope have declined significantly since 1900 because people put the fires out. Bison used to be in North Carolina and Kentucky.”

However, there is considerable disagreement among academics and practitioners as to how best to use controlled fires to maintain wilderness areas and prevent more catastrophic blazes.

“I’m all in favor of [controlled] burning,” said Arizona State’s Stephen Pyne. “I’d like to see more. But we’re talking about a complicated and expensive business.” Pyne argues that other methods of reducing underbrush and debris that fuels large wildfires are underused, for example allowing people to haul it away for firewood, converting it to wood chips, allowing goats to browse it, and selective logging.

LEARNING TO LIVE WITH IT

“I’m arguing for a slightly more complex, nuanced approach,” said Pyne. “We need to think very seriously about making controlled burning work better. It’s not going to be equally useful in all places.”

“We may need to make some adjustments,” said fire scientist and forest ecologist Kevin Ryan, director of the Forest Service’s Fire Effects Information System in Missoula. “I agree that we cannot rely entirely on fire alone, and we may need to make some adjustments. There’s probably a number of existing models that managers use to predict fire behavior and effects that need additional research and improvement.”

In the meantime, officials say that people who move into wilderness areas, like the forests surrounding Los Alamos, need to understand that fire is a natural part of the landscape. They advise making their homes more “fire-safe” by keeping yards green and clear of debris, thinning out trees near houses, and using metal, tile or other nonflammable materials for roofs.

“People who live in the woods don’t realize it could happen to them,” says the Forest Service’s Simmerman. “Some day Mother Nature is going to have fire licking at your door.”

Eye in the Sky is a weekly series that brings you the story behind the headlines using satellite imagery, remote sensing, aerial photography, and maps. This feature is developed by National Geographic News with the sponsorship of the National Imagery and Mapping Agency (NIMA) and Earth-Info. Check out maps and imagery at http://www.earth-info.org.