Fires that have turned much of Yellowstone National Park into a smoky inferno and have scared off tourists by the thousands may turn out to be a blessing in disguise, especially for the bears, elk and moose who inhabit the nation's oldest national park, officials say.

Wildfires continued to rage over vast areas within a 375,000-acre perimeter in Yellowstone. Dozens of fires were burning in Alaska, Montana, Nevada, Oregon and Washington as an estimated 15,000 firefighters battled blazes that have charred 3.2 million acres - an area the size of Connecticut - since the first of the year.Most of the acreage burned, about 2.1 million acres, is in Alaska, but only a handful of firefighters are still on the lines there as most of the 30 or so fires are being allowed to burn themselves out.

The second detachment of about 600 regular Army troops from Fort Lewis, Wash., flew in Tuesday to relieve weary crews battling the Yellowstone-area fires. About 4,000 fire-fighters were on the lines, and it has cost nearly $30 million to battle the blazes so far.

On a brighter note, the Yellow stone fires are turning stands of lodgepole pine into meadows, which officials say will not only change the face of America's original national park but will provide new food sources for its famed wildlife.

"We are witnessing a historic event of epic proportions," said park spokeswoman Joan Anzelmo. "It will change Yellowstone significantly."

Park officials say the record drought that is helping fuel the Western fires is more of a threat to wildlife than the fires, to which the animals adapt as part of their natural environment.

"The long-range benefit for wildlife will be enormous in terms of regeneration and new vegetation," said Gary Brown, assistant chief ranger.

Brown said the effect of the fires on areas of old, matted vegetation is similar to raking the weeds out of your lawn. He said much of the vegetation built up in the years before 1972 when the "Smokey Bear" theory dictated that all forest fires be actively fought.

Brown said elk herds have already been seen grazing in areas scarred by fires that have been burning since June.

One major fire was started by a careless smoker, but the rest were touched off by lightning. The only injuries to firefighters have been minor in the Yellowstone fires, although one crew member aboard a water-dropping helicopter was killed last Friday when the craft crashed while fighting fires in Wyoming's Bighorn National Forest.

"We have not lost any structures, there have been no injuries to visitors and no fatalities, but obviously the scene (for tourists) has changed from what it was two weeks ago to what it is today," said Anzelmo.

The biggest fire in the park, the Clover Mist Fire, remained at 157,000 perimeter acres. Anzelmo said it stayed within the lines Tuesday and was no longer moving toward the once-threatened towns of Silvergate and Cooke City, Mont.

But Cooke City was threatened by another fire that grew 1,000 acres Tuesday to 26,000 acres. The firefighting force was doubled Tuesday to 200.