by Carie Broecker
Rhea, a Border Collie, works with her head down, nose almost touching the ground, sniffing, concentrating, and analyzing what she is smelling. Her work is slow and methodical. When she recognizes the scent she is searching for, she will lie down, alerting her handler that there are bones, teeth, or decomposed human remains buried in the earth below her. Rhea is one of only a handful of dogs in the world trained and certified exclusively to detect historical human remains. Her resume is impressive, including searches of the Nez Perce Indian burial grounds in Kansas, locating a mass grave in the Czech Republic from 1860 Napoleon Vs. Prussians, locating the unmarked grave of a fur trapper from the mid-1800s along the Lewis and Clark Trail in Montana, and finding unmarked graves for the Washoe and Me-Wuk tribes.
Using dogs to help detect historical human remains is a rather new concept, one which may change the field of modern archeology. There are only eighteen dogs in the world certified in Historical Human Remains Detection. The dogs that seem to be most successful at this very specialized line of work are those with longer noses due to the greater number of smell receptors. The dogs must also have a strong work ethic and an over-the-top desire to please. It can take as many as two or three years of intense training with a patient handler to get a dog to the point of passing certification. Most of the dogs start their training as young puppies, imprinting on the scent of human bones and teeth when they are just weeks old.
Rhea is certified by the Institute for Canine Forensics (ICF), a non-profit organization based in Woodside, California. ICF was founded by Adela Morris, who became interested in search and rescue in 1989 after seeing dogs working in Mexico City following a major earthquake. She has since trained with six of her own dogs that became certified in live search and rescue, Human Remains Detection (HRD) and, more recently, in Historical Human Remains Detection (HHRD). Adela loved searching for live lost people but became fascinated with solving crimes, which led her to specialize in HRD. She worked on numerous cold cases with her dogs and successfully helped find valuable evidence at crime scenes.
In 1995, Adela had the idea to take her dog, Cholla, to an old cemetery to see if she would alert on very old human remains. Many of the graves in the cemetery were from 1906, and Cholla began alerting on them! Adela was astonished, and that was the birth of Historical Human Remains Detection.
Adela began training her dogs exclusively in HHRD. She knew the importance of specializing in this narrow field so the dogs could become experts and not be confused by HRD work, which looks for much more recent human scent; or live search and rescue work, which requires a completely separate set of techniques. The limits of what these dogs are capable of are still unknown. So far they have been able to detect historical human remains as far down as nine feet and as old as two thousand years, although the majority of the finds are no more than four feet down and one hundred to five hundred years old.
Adela and her team of dog handlers are also researching and documenting what conditions are ideal for HHRD work. Cool, moist conditions are best, but dogs can acclimate to working in hot, dry conditions if necessary. Working with loose soil is easier than working in dense clay. The handlers keep track of the ground temperature, which can reach well over 100 degrees on a warm day. Higher temperatures are harder on the dogs, but more water, rest, and shorter search sessions keep them fresh in tough conditions. Adela has also discovered how scent travels. Scent from decomposing bodies can travel “down stream” like water and can “pool” up around barriers such as trees. These are all factors that handlers must be aware of and learn to deal with when working a site with their dogs.
With the help of anthropologist, Dr. Lorna Pierce, Adela was introduced to several archeologists. When she told them that her dogs were becoming efficient in detecting historic human remains and offered her services, they were skeptical.
Over time Adela and her dogs were able to document their value to the archeologists and are gaining warranted respect in their field. Research is an important aspect of their work. The field is in its infancy, but they are already participating in studies using Ground Penetrating Radar (GPR), which double- checks where the dogs have alerted. The GPR documents that there was, in fact, an anomaly where the dogs alerted.
Training these dogs to this level of expertise is a full-time job. Adela and her team of handlers train with their dogs three days a week as a group and then at least one other day a week individually. The group trainings take place in locations all over the Bay Area. Adela or another member of the team sets up searches by hiding bones and teeth just below the ground. The handlers are not aware of where the items have been hidden, so they do not inadvertently give nonverbal cues to their dogs regarding where to alert. There may also be decoys in the search field such as gloves, metal boxes or other scents associated with archeology that the dogs must learn to ignore. If they alert on one of these items, there is no reward so they quickly learn not to alert to them. When they alert correctly, they get rewarded with a special toy. Training is always done with positive reinforcement techniques.
This is an exciting new field utilizing the amazing abilities of canine scent detection and the willingness of canines to work with and for humans.
Other notable ICF archeological projects include: WWII Dive-bomber Crash Site in Watsonville, California; Bayley House Family Plot (1896) in Pilot Hill, California; Boca Cemetery (1866) in Truckee, California; Donner Party Campsite Search in Alder Creek, California;
The Institute for Canine Forensics is a nonprofit organization whose mission is to promote and elevate professionalism in the use of specially trained canines for forensic evidence and human remains detection. Their research provides needed information on canine olfactory capabilities in relation to forensic evidence investigations. For more information or to make a donation visit www.k9forensic.org.