Last night, a lovely friend sent me a video of a dog she is thinking of taking on. The dog was staring at the light and shadow patterns on the floor in the home and trying to catch them. This behaviour, often known as light or shadow chasing, is part of a suite of other behaviours that I realised I’ve never written about. These behaviours, depending on a number of factors, might be known as stereotypies or compulsive behaviours. Sometimes you may hear these behaviours referred to as ‘Canine Compulsive Disorder’.

These behaviours might include:

  • circling: pacing or running in circles
  • tail chasing: attempting to chase and bite their own tail
  • mutilation: repeatedly biting and damaging body parts including limbs, feet, flanks and tails
  • licking and nibbling (also causing acral lick dermatitis and granuloma) : repeatedly licking or nibbling body parts including limbs, feet, flanks and tails
  • fly snapping: trying to bite invisible flies
  • light or shadow chasing: trying to catch moving light reflections
  • trancing: walking slowly backwards and forwards under plants or soft furnishings
  • licking non-nutritional surfaces like walls, beds

In reality, stereotypies can include a much wider list than these behaviours, but most of these would be considered normal under usual circumstances, so I don’t want to get alarmist and send hundreds of people to the vet in search of a behaviour consultant, medication or a veterinary behaviourist. However, behaviours such as masturbation and humping can also take on elements of stereotypy.

How would you know if your dog has a stereotypy?

The first thing is that the behaviour is usually seen as a movement that is repeated over and over again in largely the same manner.

Is Lidy’s circling before we go out for a walk a stereotypy? I’d say not. It is repeated and it is practically an identical circle each time, but it’s the last 30 seconds before we go out for a walk.

Is Heston’s fly snapping a stereotypy? No, because there are actual flies.

They can occupy a large part of the animal’s wake time. This was why the first thing I asked my friend was how long the dog spent trying to chase shadows every day. If a dog is suddenly excited by the reflection of their collar tags on a sunny day, that’s a lot different from a dog who spends hours every day performing the same ritualised behaviour. Stereotypies can often be difficult, if not impossible to interrupt.

Sometimes they might not be evident to us. How do we know whether licking is a stereotypy if the animal never damages themselves or we don’t see it?

Stereotypies are not only repetitive and largely unvarying, they are also unproductive. What I mean by that is that they don’t seem to have a purpose or a function. This is one reason a medical rule-out is necessary. Another friend’s dog has just had surgery on his foot and it reminded me of a dog we took into the shelter a few years ago who’d licked most of the fur off his hind leg. A quick x-ray showed that he had an infection in the bone and some necrosis. Removing the metatarsal and a heavy dose of antibiotics and the ‘stereotypy’ stopped. In other words, his licking and nibbling had a function. It was a site of pain and just like scratching an itch, it was perhaps comforting, perhaps an attempt to remove the pain, perhaps both.

Even things like fly snapping can have underlying medical causes. For dogs who have a lot of ‘floaters’ – you know those moving pieces you sometimes seem to get on the surface of your eye – you can see how that could be interpreted as a fly you can never catch.

Ruling out medical causes is vital. Even things like licking walls and beds can be underpinned by health issues. Licking non-nutritional surfaces is a symptom sometimes seen in dogs who have gastrointestinal problems such as irritable bowel syndrome and chronic pancreatitis (Bécuwe Bonnet et al. 2012). When Amigo used to occasionally lick the plastic of his dog bed, a quick chat with the vet and some stomach pills sorted him right out. Even things like compacted anal glands can lead to behaviours that seem stereotypical in nature. Tilly’s ‘froggie tongue’ or repetitive air licking was always a signal that she had an upset stomach as well.

It can really help the vet to know if the behaviour is directed at a specific body part, which can indicate something going on beneath the surface. If you’re going to the vet because you have a problem behaviour, make sure you explain how frequently you see the behaviour and when you see it. Vets aren’t good at guessing what’s wrong if you don’t tell them this is happening for three hours in a row.

It’s not unusual for the vet to clear the dog and say there’s nothing wrong with their eyes, their stomach, their anal glands or their bones. Usually, stereotypies are seen in captive animals who don’t have opportunities to forage or behave naturally, so your vet might have a point. You’re no doubt aware that seeing stereotypies is one of the most alarming signs of poor welfare in zoos, for instance, but it can also happen in farm animals too, as well as animals in lab. Keeling and Jensen (2002) say that stereotypies often occur when animals are prevented from performing ‘normal and strongly motivated behaviour patterns’, for example behaviours related to foraging or exploration. For this reason, working with a behaviour consultant who has a strong understanding of species-specific behaviours can really help.

Keeling and Jensen also point out that prey species who spend a lot of time foraging tend to develop oral behaviours, and predatory species like dogs tend to develop motor patterns like circling and pacing. That said, we’ve tinkered so much with dogs in making breeds that we also need to talk about genetic factors. I will talk about solutions later, but poor welfare and lack of opportunity to do ‘dog stuff’ isn’t the only other thing to rule out besides current medical health.

For instance, if I tell you that one of the behaviours is most often seen with shepherds, in particular the German shepherd, you’ll begin to see what I mean. In kennels, German shepherds, and sometimes Malinois or Dutch shepherds, can start tail chasing. If someone tells me their dog is chasing his or her tail, I’d put money on a shepherd or a terrier. Not something we often see in the shelter, but if someone tells me they have a dog chasing lights and shadows, it’s often a setter or a spaniel. Funnily enough, when I said this to my friend who’d sent me the video, she told me of a friend of hers who’d had an Irish setter who’d done the same. Setters, springers, sprockers, cockers, Brittany spaniels and all their cousins do seem to have a thing about repetitive behaviours.

Other breeds seem to go more for specific body parts. I’ve had three German short-haired pointers who had repetitive behaviours related to their feet and pads. It’s well-documented about flank sucking in the doberman. Collies are another breed who tend to fall into light and shadow chasing. Trancing seems to be an English bull terrier or greyhound thing.

That said, for every breed, there are outliers and anomalies. I’ve seen cockers trancing and flank sucking in many other dogs beyond the doberman.

My personal opinion is not that dogs have a genetic predisposition to develop stereotypies as such. Any dog can develop compulsive behaviours. That said, fearful natures can be inherited and there can be comorbidities with fearfulness in my experience. Also, geneticist Elaine Ostlander and her team have done a lot of work on the genetic factors behind canine compulsions. I do think, however, that when particular breeds are distressed for a number of reasons that I’ll explore shortly, or they’re not getting their needs met, or they’re in ill health, then these underlying issues tend to appear in oddly predictable ways.

Often, stereotypies appear early in life (Tiira et al. 2012) and can be present from 3-6 months, so it’s important to make sure you pay attention to your dog’s wellbeing during this time. There’s a little evidence in that same study that stereotypies can be more prevalent in dogs removed too early from their mother, suggesting developmental causes alongside genetics and nurturing.

Of course, being in a shelter, you can see many of these behaviours. Stressful experiences and change can often trigger these repetitive behaviours. For some dogs, they seem to be a way of coping. Lidy self-regulates by circling and pacing, as many of her Malinois brethren do. Thus, stress – whether acute or chronic – can worsen stereotypies. Stress doesn’t necessarily need to be some kind of traumatic experience: anticipation, frustration and excitement can also contribute to stereotypies. We’ve had a number of dogs who’ve damaged their tails (all malinois or shepherd crosses) either by chasing them or biting them who’ve had to have amputations, all of whom presented with some pretty sad and disturbing behaviour in the shelter, often despite being medicated, who went on to show those behaviours very rarely in the home. I’m also going to mention coprophagia here as well, as we see this as a sterotypy in the shelter too.

So what do we do when we recognise our animal might have a sterotypy or compulsive behaviour?

The first thing to do is accept that it’s usually multi-factorial. There are usually a number of contributing factors to the development of stereotypies including genes, personality, underlying medical factors, environmental triggers and behavioural consequences. No one thing will usually resolve your dog’s behaviour in entirety. There are no quick fixes and there may need to be many things to trial.

The second thing is create a journal. This doesn’t have to be very long, because these behaviours often cause welfare issues. However, a journal of two or three days is a good starting point.

Note how long the dog performed the behaviour. Note if you or any other individual (including your animals) tried to intervene, and how the dog responded. Note any variations. Then take the dog to the vet. A journal also helps you look back and see accurately and without bias whether there has been progress or not. There can be set-backs when dealing with stereotypies or compulsions, and it can be hard to see that in fact, it’s not actually as bad as it used to be. Also, we tend not to see that 20 minutes has now turned into 2 hours as we get used to the deterioration.

The vet may rule out underlying medical conditions or they may not. You may find that even if they give you treatment for a very clear medical condition, the dog continues to perform the behaviour – just less than they did. This may not be a sign that the cause hasn’t been treated, just that repetitive behaviours become habitual and it ends up being just what the animal does. Even if you get treatment or surgery, you will probably need to work with a behaviour consultant to make some changes to the dog’s life that minimise the chance of the dog reverting to that behaviour under stress.

One thing I often find is that if the dog has had a behaviour where they have been nibbling, licking or biting themselves, even if they haven’t damaged their skin, regrowth can cause a tingling sensation that can cause the stereotypy to recur, so it’s worth discussing a trial of anti-inflammatories or mild sedatives with your vet.

Know as well that behaviours can recur under stress in the future, even if the dog has had a long period of behavioural remission. Be mindful that sudden and stressful events can cause the behaviour to return.

Once you have sorted out appropriate treatment or ruled out medical causes, it’s time then to have a really good look at the animal’s life. A dog who is anxious or fearful a lot of the time may benefit from a consultation for behavioural medication. Clomipramine or Clomicalm has had a number of trials with dogs who have stereotypies such as tail chasing (Moon-Fanelli and Dodman 1998)

There may be a benefit to checking out your dog’s diet anyway, as some small studies have found that vitamin supplements have decreased performance of compulsive behaviour. We’re learning so much about the gut microbiota and behaviour but the fact that a number of these behaviours correlate with poor intestinal health is one sign that diet is worth investigating. As always, diet is never going to cause an instant change in your health and behaviour, so effects may be gradual. Ok, those Haribo sours make me high as a kite, but the spinach I eat to improve my iron levels isn’t going to turn me into a well-adjusted person any time soon. Some foods may have an instant effect where others may take their time. Still, Tiira et al. (2012) did find that some compulsive behaviours decreased when the dog was given supplements.

We tend to think that such behaviours are medical or genetic, rooted in welfare and coping skills, and that can lead us to overlook the consequences of the behaviour for the dog, making it very difficult to extinguish the behaviour completely.

It’s very important when you’re doing the journal to make sure you take a video of the dog when you are not present. It sounds odd, but some dogs increase their behaviour as it gets attention. Even if you are telling the dog off or you are just looking at the dog, this can reinforce behaviour and you will need to be aware of that. If the dog does less of the behaviour when you’re not present, then that tells you something important: you are a factor. Sometimes, it can be that we inadvertently contribute to the stress of others around us. Other times, it’s purely that we’ve laughed at the terrier chasing their tail or we’ve not realised that we pay attention to the dog every time they do the behaviour. One thing I saw with the video my friend sent me was that every time the person holding the camera spoke, the dog moved position. Professor Susan Friedman gave the example of a flank-sucking doberman in her Living and Learning with Animals course… a behaviour often seen as ‘purely’ genetic. What video showed was that the dog sucked their flank more when the guardians were present than when they were absent. This is vital information. Our relationships are a factor we need to consider. One tail chasing dog in our shelter only span when people passed his kennel. At other times, he was relatively calm. It may be a coping mechanism but we still need to rule out our own involvement in the situation. This can be tough, so a behaviour consultant will be better placed to help you decide, and to understand just how your behaviour is influencing the situation.

Other times, dogs have performed more stereotypies in the absence of company. This usually has two mechanisms. The first is that our presence has stopped the dog doing the behaviour as much. We’re a punisher. I don’t mean to say we’re smacking the dog or reprimanding them, just that our presence might reduce behaviours and the dog then is more able to do what they feel the need to do when nobody is present.

Our presence can also be comforting to the dog and relieve some of the stress. Many people who call me when their dog has what appears to be a compulsive behaviour, we do need to rule out separation-related behaviours if the dog is doing more of it when the guardian is absent. However, as I said in the last paragraph and here, our presence can either simply inhibit the dog or can even comfort the dog. It might be nothing at all to do with their inability or ability to cope without us.

Besides our presence inadvertently reinforcing the behaviour, punishing the behaviour or removing the need to perform the behaviour, dogs can also be performing the stereotypy for their own internal reinforcement. Injuries and locomotion cause the body to release opioids and endorphins. I can attest to this having done a marathon with shin splints and a dodgy Achilles. Locomotion can be stimulating in itself. Many of us have little repetitive behaviours that we don’t even notice, from hair flicking and touching to finger tapping to tapping our feet. I’m a compulsive shredder. Some days, I find little piles of the tag from my tea bags in a little pile next to my laptop and I have no idea how they even got there, shredded into tiny, tiny pieces. This might explain, though, why dogs removed too early from their mothers can be at risk of developing stereotypies. What we know from rats is that maternal licking builds more robust offspring. Perhaps if dogs are removed too early from the home or they have mothers who do not care for them in the way they should, they may be less able to cope with life’s little stresses. Who knows? It’s not beyond doubt, however.

Knowing the causes is essential. Only when you know the causes can you effectively and efficiently reduce compulsive behaviours. Otherwise, it’s a bit like throwing spaghetti at a wall and hoping something will stick. If your dog needs medication, a change in diet or dietary supplements, if they have underlying anxieties or maladaptive responses to stress where behavioural medication may help, if you try and deal with your dog’s behaviours without these, you are likely to be much less effective than you could be. Since stereotypies are a welfare issue, it’s vital we deal with these quickly and effectively otherwise we are prolonging our dog’s suffering. Just because the dog doesn’t seem to be in pain or suffering from spending 4 hours a day chasing shadows in the kitchen doesn’t mean that it’s a harmless activity.

Likewise, if your dog’s behaviour is caused by them seeking sensory stimulation, if it is related to coping with stress or if it is related to your presence, if you don’t understand an aspect of this, you’re less likely to find that one piece of spaghetti that really will stick to the wall. If you want a resolution, you absolutely have to have an understanding of the many factors currently contributing to your dog’s behaviour.

Once you understand the problem, you can work with your vet and a behaviour consultant to manage the behaviour, to modify it and to medicate if necessary.

Management may involve preventing the dog from accessing places where they perform the behaviour, or using things like Elizabethan collars to stop them chewing their tail or flank sucking. It might involve shutting the curtains on sunny days, removing collar tags or jewellery that’s causing light to dance, even preventing your dog from accessing the yard on brightly lit days, or only accessing parts of the garden where there are no shadows moving. Management doesn’t prevent the need to perform the behaviour, however, so muzzling, restricting the dog, removing lights and shadows won’t stop your dog. We had to unfortunately amputate the tail of a dog who was damaging their tail in the shelter. The vet said at the time that removing the dog’s tail wouldn’t change much and the dog might then refocus on other body parts. Behavioural medication and anti-inflammatories played a large role in management and treatment too.

Management can also involve providing environmental enrichment for the dog. For me, this is one of the key ways to treat stereotypies and compulsions. The right level of physical activity, the right level of mental stimulation, plenty of opportunities to be more dog, and you’ve got a dog who’ll cope better. That might involve social relationships and friendships. I suspect my friend’s home with her two dogs will reduce the light chasing of the dog in the video she sent me. Plus, my friend has dogs who are dogs. They go on long walks, they smell, they do dog things. It’s very hard with busy, working dogs to offer them the level of support that will meet their needs, and I think there’s a clear correlation between dogs bred for work and the performance of some of these behaviours. French Brittany spaniels and setters are ‘busy’ dogs, like collies can be… a sedentary, sedate life is one that some find it hard to cope with. Overdoing the physical exertion can make things much worse, so offering lots of dog-specific enrichment is an absolute essential. My little cocker Tilly did not have stereotypies when she arrived, but she was a nervous, aggressive, piddling ball of anxieties… Being more dog and having a good bond with me turned her into an almost well-adjusted dog. Even so, for a lazy little spaniel, she still had more stamina for enrichment activities than any other dog I’ve ever had (including three malinois!) and therefore a book like Allie Bender & Emily Strong’s Canine Enrichment for the Real World is an absolute boon. Think of your dog’s social relationships, their ability to play interactively, their bonds, their mental enrichment, being more dog… Play can often meet our dog’s needs, and I find that many dogs with stereotypies have developed them in lieu of other dogs or people who’ll interact with them. I find that really sad. Play is a very underestimated cure for many ailments, but it has to be interactive. Dogs are social species, and a lot of their malaise can come from a lack of appropriate social contact. This doesn’t mean solely play with other dogs. Play with humans can be just as fulfilling. I’ll never, ever forget Lidy’s first morning at home. Despite having been three years in the shelter with all kinds of dogs, she had never played with them. I’d never even seen her try to play with another dog, though she’d played often with me. The first thing she did with Heston that first morning was try to play with him. She plays like someone who has brought knives and throwing stars to the playground, but even so, the fact that she tried to engage in a bit of conspecific play for the first time in three years showed me that she finally felt safe. Dogs, like humans, aren’t designed to be starved of relationships.

Watching dogs with stereotypies can be hard. It can also be something we laugh at and don’t understand because we fail to see what it is. Understanding these maladaptive behaviours for what they are is the first step in addressing them. Stereotypies are often multifactorial. It’s not just a case of throwing the dog a stuffed Kong from time to time. It’s so much more than that. It’s not something that you can often deal with in isolation, though I’ve known dogs with stereotypies in the shelter stop them completely when moving to a home. If you’ve got a dog who is exhibiting any of these behaviours, you might need to work with a team of people including your vet and a behaviour consultant, but prognosis is often very good when you do.

My book Client-Centred Dog Training: 30 Lessons for Dog Trainers to get Maximum Engagement from Your Clients is out now


Bécuwe-Bonnet, V., Bélanger, M., Frank, D. et al. (2012) Gastrointestinal disorders in dogs with excessive licking of surfaces. Journal of Veterinary Behaviour 7:4 pp.194-204

Keeling, L. and Jensen, P. (2002) Behavioural disturbances, stress and welfare in Jensen, P. (ed) The Ethology of Domestic Animals. Wallingford: CABI

Moon-Fanelli, A. A., and Dodman, N. H. (1998) Description and development of compulsive tail chasing in terriers and response to clomipramine treatment. Journal of the American Veterinary Medical Association 212:8 pp.1252-1257

Tiira, K., Hakasalo, O., Kareinen, L et al. (2012) Environmental effects on compulsive tail chasing in dogs. Plos One. 7:7