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    Dogs sniff out cremation ashes amid wildfire destruction

    With cremation on the rise, more Americans are keeping cremains of loved ones in their homes. As larger and fiercer wildfires destroy communities in the West, archaeologists are teaming up with scent detection dogs to find ashes among the ashes.

    ByAlissa GreenbergNOVA NextNOVA Next

    Echo, a scent detection dog, alerts to a locus of human cremains scent in the former home of Marc Pandone. Image Credit: Lynne Engelbert

    Driving the road to Marc Pandone’s house in Napa, California, it feels a little like the color is leaking out of the world. A two-lane highway winding through groves of golden oak slung with bits of seafoam moss is soon surrounded by the silver of burnt treetops, which eventually give way to the deeper black of charred soil. 

    The slope leading from Pandone’s gate up to where his home of 28 years once stood is a foreboding dark brown brushed clean by flames. Inside the steel frame that outlines the footprint of the house, drifts of broken crockery and tangles of electric wire take up one side; a burnt-out washer-dryer and refrigerator slump together on the other. In what was once the front yard sit the soiled remains of a swimming pool, cover still on.

    On this November morning in 2020, a cluster of people move with purpose next to that pool in the hazy autumn sunlight. They pull on plasticky coverall suits and puncture-proof gloves, tie the laces on sturdy boots, and pour water into bowls for the six dogs they’ve brought to the site. Finally, the team circles up to discuss their goal: find, among the twisted beams and heaps of burnt detritus, the ashes of Pandone’s father, Vincent—a World War II veteran who helped liberate part of the Buchenwald concentration camp and died at 84. 

    Urns and other vessels used to store human ashes rarely survive a wildfire, so archaeologist Alex DeGeorgey is well aware that this task—recovering the ashes of a person among the ashes of a house—seems implausible. Homes destroyed in wildfires don’t look like those that have seen regular structure fire, he says. “These houses often burned over 1,000 degrees for several days. There’s nothing left.” The furniture is reduced to inches of ash, the refrigerator melted. What survives are items that have already met flame: children’s ceramics, cast iron. “I’ve done this hundreds of times,” he says of cremation ash recovery, “and I still marvel that we’re able to do it.”

    DeGeorgey and his colleagues are able to accomplish this feat through a mix of applied archaeology and canine olfaction science. His group, the non-profit Alta Heritage Foundation, brings dogs trained for human remains detection to wildfire sites, where they identify the approximate location of lost cremains—as human ashes are often called—by their scent. Then the archaeologists move in, using tried-and-true techniques to excavate the area and attempt to recover a homeowner’s loved one. It’s work, he’s discovered, that reveals hidden emotional stakes in already tragic wildfire seasons and truths about how Americans reckon with death.

    Burned homes in the Berryessa Highlands neighborhood, a short distance from Marc Pandone's house, after the Hennessey Fire engulfed the area in August 2020. Image Credit: Jane Tyska, East Bay Times via Getty Images

    In his day job, DeGeorgey runs an archaeology consulting firm in Santa Rosa. He vividly remembers the 2017 Tubbs Fire that destroyed much of Sonoma wine country. “That was a very terrifying event,” he says. “We lost 8,000 homes.” Not long after the fire, a coworker came to him distraught: He had lost the ashes of both his mother and father when his home burned and felt terrible that they wouldn’t be put to rest the way they had wanted. A friend of DeGeorgey’s had recently worked with an organization called the Institute for Canine Forensics (ICF) on a project searching for Amelia Earheart’s remains. He got in touch to see if they could help. ICF sent canine search specialist Lynne Engelbert to the site—and the search was successful.

    The first cremains recovery DeGeorgey helped complete, not long after, was enough to show him the power of this work. The client’s brother had been murdered at age 25. “I turned around and gave him his box, and his knees buckled,” he remembers. He and Engelbert decided to keep working together, and from there, word spread quickly. Community members told their friends, local newspapers wrote articles, “and suddenly we had 40 signups,” he says. 

    This year, the rate of cremation is on track to reach 58%. And by 2040, the association projects that number will rise to more than three quarters.

    That demand seems only likely to climb thanks to two parallel trends. Wildfires in the American West are becoming larger and fiercer as climate change intensifies droughts, leaving hundreds of millions of trees dead and ready to burn. And at the same time, American rituals around death are also shifting. According to the American Funeral Directors Association, in 2010, just over half of Americans who died were buried and 40% cremated. But things are changing fast. This year, the rate of cremation is on track to reach 58%. And by 2040, the association projects that number will rise to more than three quarters. Add to those statistics the results of the informal polls DeGeorgey takes at his own lectures—which indicate 15% of his audience keeps cremains at home—and that adds up to a lot of people who might one day need his services.

    Even with so many people in need, “there’s no playbook on how to do this” in the world of archaeology, he says. He’s learned by experience how to better work with the dogs, making sure to speak in a hushed voice and give them time to get used to the scent. And he now asks clients waiting for an excavation to refrain from searching themselves. “That disturbance makes it so much more difficult to find what amounts to a small pocket of ash in a huge burned building,” he says.

    In the many cremains recoveries he and the team have completed since the Tubbs Fire, they’ve learned that there are many reasons people want to find cremains. Some find great comfort in even metaphorical proximity to their loved ones. Often, a married couple hopes to be mixed and spread together, so a child holds onto the ashes of one parent until the second parent dies. Maybe a person has given specific instructions on what to do with their ashes, and there hasn’t been time to make that happen. 

    And sometimes circumstances just make following those instructions impossible. A few years ago, ICF participated in a recovery for a family whose father wanted his ashes to be buried in a military cemetery in the northern California town of Redding. The burial was postponed when the Carr Fire ripped through Redding in summer 2017. Then, before a second burial date could be arranged, the family’s home burnt down in the Camp Fire that destroyed nearby Paradise.

    Border collie Jett searches Marc Pandone's burned out home for the scent of human cremains in November 2020. Dogs working with ICF have been able to sniff out bodies buried decades prior and remains at an archaeology site dated at 9,500 years old. Image Credit: Lynne Engelbert

    Hours before dawn on Monday, August 17, 2020, the Bay Area was battered with a series of extraordinary thunderstorms, bolts of lightning arcing down onto drought-parched oak woodlands by the thousands.

    Pandone and his wife, Wendy, had lived in the house on the hill for nearly 25 years before she died of cancer in 2016. Since then, he had been passing time there alone, unable to bring himself to leave a home and studio full of her belongings and art. Alone in the house, he was woken by the tumult at two o’clock in the morning. “It's crashing, it's windy,” he remembers. “I thought the place was going to catch on fire that night.” When it didn’t, he cautiously began his week, turning on his generators to make up for the absent power and teaching the first Zoom classes of the semester at the community college where he is an art professor—even as small fires burned less than 10 miles away, sparked by lightning strikes.  

    On Tuesday morning, he climbed the neighboring hill, noting the smoke hanging in the air despite the cool breeze. At 1 p.m, ash began to fall from the sky, from what would soon become known as the Hennessy Fire, and he went to gather up his cats. When he lost internet service—and with it, use of his cell phone—he knew it was time to go.

    He took the cats, some of his artwork, his teaching materials, and some important documents. During previous fire scares, he had always made sure to grab the urn with Wendy’s ashes and the cardboard box that contained half of his father’s cremains, which awaited their last, requested trip to Brooklyn for scattering at the family plot. He would even buckle Wendy’s urn in the front seat with him on his way out of town.  

    This time, Pandone left the most personal items; it was just too painful, he says. No urn in the front seat. And no bag of Wendy’s journals, which he picked up and then put down again on his way out, without quite knowing why. “That bag of journals haunts me,” he says, eyes glassy. Instead, he used his phone to record a last walk-through of the house and studio, then got into his car and drove away.

    The fire roared over the ridge less than two hours later. 

    Today, three months after his home burned, the scene is not much different from what Pandone discovered once the flames had abated: ruined appliances, broken tile, a thick layer of dusty drywall. But in a profound stroke of luck, he had been able to find Wendy’s ashes quickly, still in the kiln-fired urn she had made herself as a ceramicist. He had already scattered some of them from atop a Venice bell tower and he quickly emptied the rest on the hill next to the ruined house, where trees still smoldered. She had loved this house, after all. No more putting it off. He wanted her at rest.

    Finding his father presented a more complex challenge. The ashes hadn’t been in an urn, but in a box on a shelf in a study crowded with rare vinyl and first edition books. So when Pandone heard through word of mouth about the team helping people find cremains, he hurried to sign up.

    Scent detection dog Piper alerts to the scent of human remains. Dogs’ ability to identify remains can border on eerie. When Lynne Engelbert’s husband died in 2006, she had him cremated, and brought the family dog with her to pick up the cremains. As the worker brought out the cremains, she remembers, the dog began to whimper and whine, nuzzling the paper and cocking his head in confusion. “Oh my God,” the burial services worker said. “He knows who that is.” Image Credit: Alissa Greenberg

    To start the search today, Engelbert’s dog Piper picks through the wreckage of Pandone’s home, stopping to sniff around the burnt-out fridge. Occasionally she looks back, questioning. “Keep working,” Engelbert tells her. Finally, she “alerts,” lying down near where the wall to the study once stood. It’s a signal indicating a “scent pool,” rather than a specific point source, Engelbert explains. The smell of the cremains is everywhere, the gesture says, having gradually spread out in the months since the fire.

    Next into the house goes Piper’s colleague, Echo. Maybe she can make more sense of the chaos of the scent pool. “It’s your decision,” her handler Karen Atkinson tells her, when she pauses as well. “It’s up to you, baby girl.” But ultimately Echo too lies down in the dust, disoriented.

    That a dog can smell cremains in the aftermath of a wildfire at all is a wonder of evolution. And although some people may think dogs’ abilities are “more folklore than fact,” multiple studies have supported what practitioners like Engelbert and Atkinson already know, says Ken Furton, a forensic chemist at Florida International University who has studied dog olfaction for 25 years. 

    The first factor that makes canine olfaction so powerful is anatomy. Dog noses direct part of the air they inhale straight into their olfactory epithelium to be analyzed, says veterinarian Cynthia Otto, director of the Penn Vet Working Dog Center. And the unique structure and airflow inside a canine nose allows for continuous scent detection while a dog both inhales and exhales. 

    Plus, that olfactory epithelium, tissue at the back of the nasal cavity that processes olfactory signals and delivers them to the brain, is 20 to 30 times larger in dogs than in humans, with twice as many odor receptors. And dogs are also great at organizing all that data, sorting through the chaos to pick out individual volatile organic compounds (VOCs)—carbon-based molecules that shed off surfaces and float around in the air, creating their scent. “If we humans walk into a bakery, we can say ‘someone’s baking a pie in here,’” Engelbert says. “A dog would walk in and say, ‘oh someone’s baking a pie in here, and it has apples, and butter, and cinnamon, and nutmeg.”

    They had been seeking to disprove the claim that dogs could pick up scents from material that had been through such high temperatures, but the dogs were able to sniff the small amount of exploded debris and correctly identify individuals who had been in contact with the bomb pre-explosion 82% of the time.

    Living humans constantly put out scent made up of hundreds of VOCs, Furton says, from a mix of sloughed-off dead skin cells, bacteria and their waste, and the products of our sweat glands. And fresh human remains are caught up in the elaborate chemical processes of breakdown by microorganisms, releasing hundreds of compounds with names like “putricene” and “cadaverine.” But identifying the specific chemical, or group of chemicals, that dogs like Piper and Echo follow in their search is virtually impossible, he says, calling the question “one of the largest knowledge gaps” in his field. “In most cases we don’t know exactly what a dog is alerting to.”

    Preliminary data suggest that the VOCs that Echo and Piper are picking up today aren’t the same as those that dogs would identify from recently deceased or long-buried bodies (though there may be some overlap). Furton theorizes that that’s because the source of many of those VOCs—active biological processes in live humans or decomposition processes in dead humans—aren’t present in cremains. In a way, it’s surprising they continue to have a scent at all.

    Still, he points to a study in which he and colleagues blew up a car and then asked detection dogs to follow a human scent trail from the resulting bomb shrapnel. They had been seeking to disprove the claim that dogs could pick up scents from material that had been through such high temperatures, but the dogs were able to sniff the small amount of exploded debris and correctly identify individuals who had been in contact with the bomb pre-explosion 82% of the time. So even though cremains have also been subject to extremely high temperatures, it’s not surprising that dogs can pick up some compounds in the material, he concludes—even if we’re not sure what exactly they are.

    And ultimately, “detection is detection,” Engelbert says. “You tell the dog what you want them to find and you teach them how you want them to tell you about it”—to sit, lie down, or bark. One method, Otto says, is positive reinforcement: exposing the dog to an odor and rewarding them when they sniff it, then making it progressively harder to find the odor source that will get them that reward. For training dogs on unburnt remains, such as ancient skeletons, Engelbert and other ICF handlers sometimes use teeth they get from oral surgeons. For cremains, they wrap tiny amounts of cremation ash in unbleached muslin bags and hide them, and also take dogs to practice on location at as many wildfire sites as possible.

    Training on a variety of materials in this way is important because one of the challenges of training a dog for human remains detection is teaching the dogs what’s similar to but not the same as what they’re looking for: not animal remains, not live human beings. But at the same time the search window can’t be too narrow either. “We have to make sure it's not just Uncle George’s remains,” Otto says. “That’s too specific.”

    Archaeologist Alex DeGeorgey (right) explains to client Marc Pandone (left) the difference between human cremains and the surrounding debris ash. Image Credit: Lynne Engelbert

    With the general location of the cardboard box and the initial “scent pool” alerts from the dogs in mind, the archeologists at Pandone’s former home take over the search of the study. Working with dogs like Piper and Echo makes a lot of things easier, but there’s part of this process that can only be accomplished using the sort of painstaking observation that archaeologists excel at.

    “At first, when you walk into one of the sites you think, ‘This is impossible,’” DeGeorgey says. But experience has taught him that the best way to begin is by digging straight down to the soil through the ash, drywall, and melted glass, slowly widening the cleared patch as necessary. And he knows what he’s looking for: a discreet pocket of fine, homogenous ash about the size of a loaf of bread, light gray or brown or pale salmon in color, shot through with bits of bone. He keeps an eye out for clues he’s on the right track in the form of the valuables people often keep with cremains—military commendations, pins, wire-rim glasses, jewelry. Once, he unearthed an intact pocket watch, stopped at the time of the person’s death. Often, he also finds the medallion that’s legally required to accompany every set of cremains at a crematorium to prevent mix-ups.

    As they dig through the layers of clumpy drywall and ash, DeGeorgey and his fellow archaeologist, Maggie Breuer, unearth melted LPs, half-burnt books, and the telltale brass arc of a globe. Pandone sifts through layers of paper sadly, the images on the book covers sometimes still recognizable. At one point, Breuer reaches deep into the ash and pulls out a perfect, dusty sake cup. The nearer to the ground they get, the more painstaking the work becomes. After an hour of digging, they reach soil. 

    And then after widening the clearing, bringing in the dogs for another check, and even more digging: “I think we found him,” DeGeorgey says from a spot next to the ruined study wall. “That’s Vincent right here.” Breuer walks over, cocking an eyebrow. To the untrained eye, what he’s pointing to looks like everything else he’s dug through already.

    “It’s this,” he says, inviting her to bend down to investigate a tawny, subtly layered pile of, yes, homogeneous material. “See how when you run it through your fingers, it’s gritty?” He wasn’t sure at first, he says, because the color is slightly off. But it was the specks of bone that convinced him. They high five. DeGeorgey calls Pandone over.

    “Dad, you’re looking good!” Pandone says, with a wistful smile. To the others: “Now I’m going to have to keep my promise to him.” 

    He considers the cremains for a moment. “So, if you gave the dogs a sniff of that, what would they do?” he asks. They’d lie down, he’s told, or sit. Another pause. “Can I see that?”

    DeGeorgey and Breuer pour the cremains into a bag, leaning it against a scorched planter nearby.  One by one, the dogs sniff the bag and then sit, looking up at their handlers expectantly.

    Archaeologist Alex DeGeorgey excavated around where the dogs had alerted, locating and "pedestaling" the human cremains (shown inside the circle) in preparation for recovery. Image Credit: Lynne Engelbert

    Their provenance confirmed, Engelbert pushes the bag of Vincent’s ashes into a black plastic urn, a donation from a local funeral home. Her dogs jump into the backseat, their work done.

    Pandone watches the canine team go, looking a little at a loss. He’s staying with his partner a couple of hours south for now. The prospect of cleaning up the property and deciding what to do with it still weighs on him—but now perhaps a little less. He knows trucks will come by soon to haul the rest of the wreckage to a hazardous waste dump. “I didn’t like the idea that he was going to get scooped up and just taken away,” he says of his father’s ashes.

    Nearby, Breuer and DeGeorgey are stripping off protective clothing and starting to pack up their gear, but the mark of the experience itself is less easily shed. For as long as they’ve been doing this work, DeGeorgey and his colleagues have struggled with how to process so much sorrow. What do you say, he asks, to the woman whose son sacrificed his life saving someone from drowning at the age of 25—and whose ashes he’s collecting from the ruins of her basement? What about the man to whom he is returning the ashes of a high school sweetheart after 50 years of marriage? Or the woman looking for the cremains of her three foster children and two biological children?

    “Certain key objects define your history, ancestry, who you are as an individual.”

    Engelbert estimates that, when she volunteered after the Camp Fire that destroyed Paradise, she talked to 200 survivors, heard 200 stories of horror. The requests streaming in seemed endless. “There’s a huge need for this,” she says, “and we’re the only ones who do it.” By the end, she’d sunk into a deep depression.

    Engelbert and DeGeorgey have both sought therapy to help them handle the vicarious trauma of this work and developed new protocols to protect their colleagues from similar suffering. They’ve also partnered with an ethnographer to record the immense diversity of client stories—of lives in trailer parks and in luxury developments, in urban areas and on Native American reservations, all equally, terribly destroyed—in part so those painful stories have somewhere to go besides home with volunteers.

    DeGeorgey sees in that indiscriminate destruction a deeper truth about how human community and self are made and unmade. “­Things are not things; things are meanings,” a friend told him during one of his more difficult periods. He has taken that message with him as a sort of mantra to every cremains recovery since.

    “Certain key objects define your history, ancestry, who you are as an individual,” he says. Wildfires are uniquely capable of wiping out those objects, suddenly and fully, engendering a profoundly disorienting loss of self. In that way, he says, his work goes beyond archaeology and enters the realm of solace. Time and time again, clients break into tears or nearly faint when DeGeorgey brings them their loved ones’ cremains—an object that is somehow both single and multiple, both symbolic and concrete, both a tie to the past and a stepping-stone to the future. “That’s the only thing I wanted out of this house,” they often tell him. “I can walk away now.” 

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