Our dogs act to get our attention to communicate with us. They may bark at the door that we would understand to let them out, or scratch the cupboard door to get some treats or just sit next to us that we would pet them. A dog uses these behaviors that have produced the wanted outcome before and hopes us to react to these behaviors. It is a dog’s way to communicate.

In scent work it is common to teach a dog an alert behavior, a final response, for instance sitting, scratching or “freezing” to the hide. This behavior is also called an indication behavior. The point of indication behavior is to give a dog a mean to tell its handler that it has found and narrowed down the spot of the target scent. But how important it is for a dog to know and use a specific alert behavior?

A couple of weeks ago there was a discussion in Facebook group “Nose Work” concerning
alert behavior in dog sport called K9 Nose Work. It was based on a blog post arguing that there is no need for a taught alert behavior to understand when the dog has found the target scent: it is enough if a handler knows how to read the dogs body language to pick the right spot of the target scent and call it an alert. The blog post argued that if the taught behavior is not strong enough for the dog, the dog may be insecure at a find and even leave it unalerted. Therefore a handler should rather learn to read his/hers dog well enough to pick up it’s natural indication behavior at the hide and call it a find even without the taught alert.


When talking about the sport of Nose Work it is probably enough to read the dogs body language, at least in the first class competitions where there are no control scents or other intentionally placed distraction scents that a dog might get interested in at the search area. When the dog gets interested in a scent it is presumable that it has found the target scent. But what about when there are distractions? Another dog may have peed in the search area? Someone may have dropped smelly treats there? And what about in upper classes where they intentionally put control and distraction scents to the area?


It is natural for a dog to be interested in some scents and some scents are more interesting to some breeds than others. In general, sniffing dogs are usually especially interested in control scents that are used continuously for training. In Nose Work those would be for example cotton swabs, blotter paper, stick-on floor protectors and so on, whatever material is used with the target scent repeatedly. When a dog finds the control scent from the search area it might sniff it more intensively than the other places that area. It might look very similar to the targeting sniffing behavior at the target scent. If the handler misinterprets this as a sniffing behavior for the target scent and calls it an alert, the team will lose important points. But if the dog has a strong taught indication behavior, which is in stimulus control, it should not indicate. No matter how interesting it finds the distraction.

The other problem that may occur from the lack of a taught indication behavior is mistargeting the scent. If in the search area the air flows move the scent plumes to a different place where the actual source of the scent is located, the dog may try to find it from the place of the scent plume and not the actual place of the scent. Depending on the search area and the scents volume, the plume might be strong enough for the dog to behave like it is close to the target scent trying to indicate the spot. There is a risk that the handler  misinterprets this behavior and again calls an alert in the wrong place. If the dog is used to pin pointing the target odor it usually can differentiate whether it is targeting to the plume or the source of the scent, especially, if the source of the scent is small enough to pin point. If it tries to find the source from the plume but does not succeed, next it may try to find it elsewhere. In a competition situation, where every second counts and a handler is usually a bit stressed, this could be a place of false call of alert. But if the dog has a strong taught indication behavior, the handler can trust the dog when it is not alerting.  And the handler can even help the dog find the source by analyzing the air flows in the area and directing the dog the other way.

Some dogs’ style of searching is very inconspicuous. Especially in Nose Work, which is a sport designed for all kinds of dogs, the searching behaviors vary. Where other dogs look like going crazy when finding the target scent, some just sniff it a tiny bit longer than other places and even an attentive handler might miss if no final response exists. Usually the dogs get back to that place where they spotted the target scent even if the handler misses it the first time, but it costs in the Nose Work competition multiple valuable seconds.

Nose Work, like many other dog sports, is a hobby that is mainly supposed to be fun both for the dog and the handler.But things get more serious when the dog does sniffing for its living. Should the handlers then always need an alert behavior of not?



Depending on the scent a dog is detecting, the need to teach alert behavior varies. If we need a dog to pin point an exact source of the target odor the alert is necessary. As an example we can use search and rescue (SAR) dogs that need to show the exact place of the missing person in a rubble. The dogs need to alert the exact place where the human scent is the strongest. They need to keep on indicating the place of the strongest scent source as long as the rescue people have located the missing person to start the rescue operation. It is not enough for them just to be interested in a specific place and sniff it. The handler needs to be 100 per cent sure that the dog indicates only the living human scent and does not indicate anything else that it might find interesting. There can be lot of interesting smells in a collapsed building for a dog.
When finding small amounts of target scents like individual bugs, it is again important to find the exact location of the target scent, the bug, to know where to spread the pesticides. Thus, it is not relevant to know where there is some of a bugs scent but to find the place where the bugs are in the very moment. Likewise, a drug detection dog which is used to search vehicles in customs needs to give a clear, objectively verifiable signal at the target scent.

Some working dogs do not necessarily need a specific alert behavior due to the nature of the work it is doing. For instance in customs the detection dogs may just stand aside of a gate when people pass it when arriving to a country. The dogs stand still and keep on sniffing the air flows that come in with the arriving people. If they pick up the target scent they will walk in to the crowd to find the source of it and follow that person. Then the dog has done its work and the handler stops the person and asks him to step aside for a further inspection. However, although these dogs do not have a specific alert behavior (besides the following) for this specific task, they are still often taught to indicate their findings on luggage and post packages by some alert behavior.


There are no short cuts to a reliable alert. It takes a lot of work and practice from both handler to learn to read the dogs behavior at a hide and the dog to learn a strong, reliable alert.

First, the target scent needs to be very clear to the dog. It needs to know what is the exact target scent and what are the control and other distraction scents that it is not supposed to react on. Part of the training is to teach the dog not to be interested in anything else in the search area than the specifically taught target scent. Most of the distractions are easily taught for the dog to ignore but you can never prepare for all the possible distractions that a dog may find naturally interesting. Thus, to avoid possible misinterpreting on dogs searching behaviour, it should be taught a strong behaviour chain where the target scent triggers the alert behavior before the dog even thinks. Every time the dog finds the target scent it should react to it with no hesitation.

Second, it is useful to know your dogs body language and behavior so well, that you can see when it is on the scent and close to the target. But its gestures should not be its only way to alert, if you want to be sure and avoid any possible misinterpretations.

In the end both are important to master: understanding the dog body language and the taught, strong alert behavior. When the handler reads the dog well and the dog does the alert behavior as an almost unconscious reaction when finding the target odor, the team is effective and they can rely on each other. It is possible to cope with just another, but for the best result, it is best to have them both.