Drug dogs

A detection dog or sniffer dog is a dog that is trained to and works at using its senses (almost always the sense of smell) to detect substances such as explosives, illegal drugs, wildlife scat, currency, or blood. Hunting dogs that search for game and search dogs that search for missing humans are generally not considered detection dogs. There is some overlap, as in the case of cadaver dogs, trained to search for human remains. Some police dogs that are used in drug raids are trained not only to locate narcotics, but also persons who may be hiding from the police, as well as stashed currency. Some detector dogs can locate contraband electronics, such as illicit mobile phones in prisons.

In recent years, detection dogs have emerged as a valuable research tool for wildlife biologists. In California, dogs are trained to detect the quagga mussel on boats at public boat ramps, as it is an invasive species. Sniffer dogs have also been enlisted to find bumblebee nests. Other studies have employed detection dogs for the purposes of finding and collecting the feces of a diverse array of species, including caribou,black-footed ferret, killer whale, and Oregon spotted frog.

Detection dogs have been trained to search for many things, both animate and inanimate, including:

One notable quality of detection dogs is that they are able to discern individual scents even when the scents are combined or masked by other odors. In 2002, a detection dog foiled a woman's attempt to smuggle marijuana into a Brisbane, Australia prison. The marijuana had been inserted into a balloon, which was smeared with coffee, pepper and petroleum jelly and then placed in her bra. A sniffer dog can detect blood even if it has been scrubbed off surfaces.

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