Many working scent detection dogs have been taught to recognise several different scents. A police dog, for instance, can be able to detect many different drugs as well as the scent of explosives or cash money. Often the dog will give the same indication or alert behaviour, such as sitting down and staring at the source of the scent, for all these scents.

I recently read a discussion about changing the target scent for a dog. The problem was that the trainers had not been able to wean the dog off an older already established target scent. This meant that the dog gave an alert on the new target scent but occasionally alerted on the old target scent as well. The alert behaviour was identical for both scents.

Let’s say that a dog has been trained to detect explosives and now we want it to start working in drug detection. There is a real chance that the dog will continue alerting on explosives out of habit. Now, if the handler does not know which target scent the dog is alerting on, both the handler and the dog may be at risk.

It is clear that when we work with animals, there is always a risk that they will not perform 100 percent reliably. Many factors influence a dog’s working ability and motivation. That is why it is important that whenever teaching a new scent to a dog we stop to consider the risks that may come with the new skill. If the dog has at some point in its career learned to alert on dangerous substances this should be kept in mind whenever the dog gives an alert, even if the dog has not alerted on that substance in years. An element of risk remains even if the dog has been well weaned off the scent. In such situations a good option is to teach different alert behaviours for different target scents.

Generally it makes no great difference whether the dog alerts on different target scents in the same way or differently. Sometimes different alerts can, however, really pay off. This is the case especially if the dog is retrained for another job and the target scent changes.

Favourite alerts are behaviours that are relatively easy and fast to train and come naturally to dogs. Variations can be introduced if and when needed.

The videos below shows a dog alerting to different scents in different ways.

This dog has been taught to detect common bed bugs when given the command “Missä B’s?” (eng. Where are the B’s?) and to alert by lifting the left front paw. Bed bugs are the primary target scent for this dog, and it should always give the alert when the scent is present irrespective of what command it has been given.

The dog alerts on bed bugs. The scent line-up includes the scents of dog kibble, a moldy piece of wood, bed bugs, a small piece of a kong toy and a latex glove.

The dog has been taught to react to the scent of a kong toy as well. The dog alerts on a kong by keeping its nose stationary as close as possible to the source of the scent. The dog is allowed to react to the scent of a kong irrespective of the command, but it should primarily alert on bed bugs. In other words, the scent of bed bugs should always be the most important target. In this exercise the bed bugs have been removed from the line-up altogether.

The dog alerts to the scent of kong.

This dog started working with the scent of mold. It was taught to search for and alert on mold with the command “Töihin” (eng. Go work). The alert behaviour was to pick up the bringsel hanging around its neck into its mouth.

In the below video you can see the dog reacting to the scent of the kong toy but the alert behaviour shows this is not the target scent it was commanded to search for. The alert is rewarded verbally (because it is always ok to alert on the scent of a kong toy) and the dog is commanded to continue searching for the scent of mold.

The dog alerts to the scent of kong and mold.

The final video below shows the dog being sent to search for the scent of mold. It is given the command to search for mold and it is wearing the bringsel indicating this job around its neck. The objective is for the dog to always primarily alert to bed bugs, if they are present, irrespective of the search command or the context. In the video the dog first passes the jar containing bed bugs and stops at the jar containing mold, but returns quickly to give the alert on bed bugs as it has been taught.

The dog alerts to the bed bugs and ignores the mold.

Here is another video on different alerts in different realistic search scenarios. Should you ever see this dog working somewhere, you won’t have to guess what it finds. Just look at the alert behaviour and you will know!

This post is also available in: Suomi (Finnish)