A yellow mutt named Chance sniffs through the splintered limbs of a toppled tree and sits down near a piece of carpet that came from someone's home. It's his way of telling handler Tracy Sargent that human remains are nearby.
Such scenes are common as hope fades for finding survivors a week after tornadoes ravaged the South, killing 329 people in seven states and leaving an uncertain number missing or unaccounted for when entire communities were ripped from their foundations and thrown across hollows and hills. In Tuscaloosa alone, officials say, more than two dozen dog teams are searching a massive debris field that stretches for miles, and still more could arrive.
Chance didn't find a body this time Wednesday. The animals commonly called cadaver-sniffing dogs are trained to detect any human remains, and Sargent suspected there was blood on the rug fragment that caught Chance's attention. The dogs' noses are so sensitive that it doesn't take much for them to alert handlers to decaying human tissue including blood drops, which fell all over town from about 1,000 people being injured.
Earlier this week, Chance and another of Sargent's dogs located the body of a University of Alabama student as his grieving father watched. It only took the dogs minutes to locate the remains in a maze of twisted trees and debris that had been searched by humans for hours.
"(The father) went over there and bent over and touched his son and started talking to him. And he hugged him, started crying, and told him that he loved him and that he would miss him," said Sargent. "That in itself is why we do what we do."
The body was found about 300 yards from the concrete slab that had been the student's home, an indication of the difficulty searchers have even knowing where to look.
It's uncertain when the last survivor was pulled from the rubble in Tuscaloosa, where officials say 41 people were killed when an EF-4 tornado with winds up to 190 mph mowed down some of the city's most densely populated neighborhoods. Some people listed as "recovered" actually just showed up at hospitals or aid stations after being considered missing, fire officials say.
Mayor Walt Maddox fears there aren't many survivors left to rescue. Officials say 30 people are listed as missing in the city, and eight of those are of particular concern because they'd been seen in the area within two weeks before the storm.
"I'm hopeful and prayerful, but the longer that we go through this, the more concerned I become that (the death toll) will be more devastating than we could ever imagine," Maddox said.
Fire Chief Alan Martin said that despite multiple sweeps, not a single neighborhood or community hammered by the storm had been searched thoroughly enough to eliminate it from the grids used by teams to plot their days work.
"We have not totally cleared any area," he said.
That includes the Rosedale Apartments. A search and rescue crew waded through what was left of the complex Wednesday, breaking down doors with sledgehammers as a black Labrador retriever led the way through boot-high rubble laden with bicycles, children's toys, mattresses and cinder blocks.
Now in a shelter, Billie Sue Hall, 54, hopes the searchers find her friend and neighbor Betty Cunningham, whom she hasn't seen since the twister and can't reach by telephone. Hall said they talked daily, including on the day of the twister.
'"If you get out of the storm,"' Hall said Cunningham told her, '"I'll call you back."'
That call never came, though Hall acknowledges that Cunningham may be staying with a relative or may simply be safe in another shelter. Homes all over their working-class neighborhood were destroyed; it's among the areas Sargent has searched with her dogs.
Sometimes the dogs check an area because residents or workers report a foul smell; other times they zero in on a debris pile near where someone was last seen. They also sweep through entire sections of town quickly to eliminate the possibility that a body is nearby, said Sargent, who works for Georgia's homeland security agency and is participating in the Alabama search as a volunteer during her vacation.
"You don't want to check this huge area with limited resources," said Sargent, of Villa Rica, Ga. "The dogs tell us where remains are, and where they are not. Both are equally important."
Alan Blinder contributed to this report.