Rattus Norvegicus as a Biological Detector of Clandestine Remains and the Use of Ultrasonic Vocalizations as a Locating Mechanism

In investigations, locating missing persons and clandestine remains are imperative. One way that first responder and police agencies can search for the remains is by using cadaver dogs as biological detectors. Cadaver dogs are typically used due to their olfactory sensitivity and ability to detect low concentrations of volatile organic compounds produced by biological remains. Cadaver dogs are typically chosen for their stamina, agility, and olfactory sensitivity. However, what is not taken into account often is the size of the animal and the expense of maintaining and training the animal. Cadaver dogs are typically large breeds that cannot fit in small, hard to reach places, such as collapsed buildings. Another small animal could be used as a biological detector in addition to cadaver dogs. This research tried to determine if Rattus norvegicus, or a brown laboratory rat, could be trained to identify the volatile organic compounds of decomposition and return when called, and if the vocalizations could alert to the location of the clandestine remains as well. Rats were trained in increasingly larger environments using classical conditioning and positive reinforcements. It was determined that while Rattus norvegicus could be trained to find the scent of decomposition and could be trained to return when call, Rattus norvegicus did not vocalize at the scent of decomposition. Future research projects would need to be done in order to determine the full ability of Rattus norvegicus as a biological detector of clandestine remains.