Fire-Fueled Comeback

While the U.S. Forest Service usually suppresses blazes, it's a fact: Fires are often good for ecosystems

As seen from Tucson, it loomed like the flames of Armageddon. And when finally sated, last summer's Aspen Fire had devoured some 85,000 acres of juniper, oak and ponderosa. It had sent wildlife packing, and even the unassuming, endangered Gila chub had to be yanked from ash-threatened pools in Sabino Canyon.

In short, this was an ecological catastrophe of biblical proportions.

And then again, maybe not. According to some biologists, these huge burns may prove a blessing to wildlife in the long run.

John McGehee is among these biologists. A wildlife manager with the Arizona Department of Game and Fish, he pulls his Dodge Ram to the Mount Lemmon roadside to inspect hills newly flecked with pockets of green--deer grass, bear grass--and fresh deer tracks. "These areas are really coming back," he says. "This is excellent for wildlife."

Further up the mountain, he's seen skinny young Aspens poking up in groves newly cleared by fire. And the extensive brush burn-off has exposed new areas for forage to pop up. Likewise, small waterways long clogged with debris and dead leaves were suddenly springing to life.

Only a year after the fire, experts are stepping cautiously. But most agree that the burns--even conflagrations resulting from years of misguided fire suppression and brush build-up--can be a good thing. Like an immense broom, they can clear away old debris, breathing new life into forests and rejuvenating wildlife populations.

Even the embattled Gila chub got an unexpected boost: Flash floods after the fires scoured the aggressive, non-native sunfish and crayfish from their habitat.

And while it may be too early to gauge how the Catalinas will fare, the Chiricahua's Rattlesnake Fire a decade ago may lend a few optimistic clues.

"For example, before the burns, a lot of the bear habitat was choked-up with brush," says Gary Helbing, Douglas District wildlife biologist for the U.S. Forest Service. "But the fires actually broke up a lot of that area and brought back a lot of forage, including raspberries"--a favorite bear food. And broader foraging range has meant fewer problem-bears haunting the campgrounds, Helbing says.

However, the jury is out on some threatened Santa Catalina species, including the lesser long-nosed bat and Mexican spotted owl. While the bats use the Catalinas as a migratory stop-off--and may not be deeply impacted--it's too early to gauge how the Mexican spotted owl will fare.

"Those birds are already in possible decline due to drought," says Thetis Gamberg, a wildlife biologist with the U.S. Fish and Wildlife Service. "If they return to a site and are in good reproductive shape, they might be able to re-establish." But at this point, it's still a wait-and-see proposition, Gamberg says.

As for the short-term, immediate animal mortality from fire is surprisingly low. Amphibians and reptiles can often just burrow in, and highly mobile creatures like bears seem to take the blazes in stride. (Researchers radio-tracking 38 grizzlies during the 1988 Yellowstone conflagration found that 13 of the bears soon ambled back into freshly burned zones, while three more stayed in still-burning areas to feast on elk carcasses and claw ants from charred logs.) In addition, canopy-consuming fires allowed vibrant new growths of huckleberry on the forest floor--another favorite bear food.

Even the U.S. Forest Service, often blamed for its public-pleasing, fire-suppression mania, noted in a 2000 news release that flame-scarred Yellowstone is bouncing back.

"Within a few years, the burn sites were already populated with extensive wildflower displays," the release said. "And the newly burst pine seeds began a new cycle of re-growth."

Yellowstone could provide a peek into the future of the Santa Catalinas and other forests, says Dr. Dan Kashian, a fire ecologist at Colorado State University. He conducted extensive studies of Yellow National Park in the post-fire years. His conclusion?

"In the long run," he says, "fires are quite helpful, because they open wide areas for forage growth."

Mike Bader, a Montana biologist who helped fight the Yellowstone fires as a forest ranger, sees another telling change.

"I went back to the park 10 years later," he says, "and I saw trees that were taller than I am." Bader also estimates a doubling of the grizzly population, thanks to the fires that "pushed out their range."

But not all researchers share Bader's enthusiasm about big fires.

"It's too simplistic to think that fire is always good," says Norm Christensen, a fire ecologist at Duke University. "There's no question that suppression has resulted in fires on a scale that are well outside the range of natural fires. And they are not ecologically desirable."

For one thing, catastrophic fires burning in excess of 1,000 degrees can simply sterilize the soil. And in huge crown fires, for example, such high temperatures can vaporize all organ material.

Encroaching development is another complicating factor. This can have a dizzying number of effects, from reducing the paths that wildlife can use to escape, to spurring the thinning of areas around homes near fire-risk areas, such as Summerhaven.

Because of urban growth on the forest's edge, animals nearly always take a backseat to human concerns, says Norm Christensen.

"So far, wildlife and biodiversity has not received a lot of attention in policy (formation). And yet those policies are incredibly important to wildlife."

Researchers are simply watching and waiting before rendering a final verdict. Back in the Catalinas, however, John McGehee is already a decidedly happy camper.

"I'm still amazed at the changes I've seen up here," he says. "This place is really coming back to life."

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