09/10/2025
Today our breed expert Carol Price looks at a quirk in collies that is more consistently misinterpreted, or misunderstood
BORDER COLLIES, THE REACTIVE IMPULSE and when it becomes more dangerous
Collies are often called more ‘reactive’ dogs. When really what is meant is that they can become more HYPER-reactive – and defensive - towards any number of different environmental triggers. So why this happens is what this feature will be covering today.
INSTINCT AND INHIBITION
I have written a number of times in the past about the ‘lunge-nip reflex’ in Border collies, and how – rather than being a sign of any intrinsic ‘bad character’ – it is a more natural, and essential, part of their whole working repertoire as sheepdogs.
For a dog who cannot speedily defend themselves in the face of more challenging livestock could end up being trampled on, injured or even dead.
At the heart of the problem with this reflex, however, is how it may manifest, or readapt, itself in collies owned as companion dogs instead. Or how well the dog can repress or inhibit it in situations where it is less socially appropriate.
Some dogs, for instance, will never launch this reflex. Others may only launch it at your hose, broom, mop or vacuum cleaner. Or when faced with any sense of higher pressure or crowding from stranger people, or dogs, coming into their headspace. Or when other dogs come too near their ‘stuff’ (i.e. specific territory or resources). But they will never use it upon their owners. And, even under pressure, the dog still possesses suitable social inhibition to recognise that this target is ‘out of bounds’. And the same may apply to anyone else the dog lives with.
Other dogs cannot stop their nip reflexes being launched, even against their owners, once they reach a particular level of mental arousal or excitement. As can be a common experience with collies taking part in higher arousal pursuits, like Agility.
AROUSAL, IMPULSE CONTROL AND INHIBITION
So all collies can have different basic ‘settings’, when it comes to how readily they will lunge-nip and what their commonest triggers or targets will be.
But still the three key factors you have to look at in all cases of lunge-nipping behaviour in collies are these. First, how aroused the dog has become (i.e. by common emotional triggers like fear, anxiety, frustration or excitement) Or by environmental ‘crowding’/incursions by others into their personal space. Arousal of this kind always makes lunge-nipping in a collie more likely.
Second, does the dog have poorer impulse control in general? E.g. finds it harder to focus, wind down, wait anywhere, and gets more restless – including spinning - whiney or barky whenever they cannot do what they want to do more immediately? (Though note these can also be signs of a wider, ongoing anxiety problem in a dog). For there is nearly always a link between poorer impulse control overall, in collies, and a more readily activated lunge-nip response in them.
Last, does the dog have poorer social recognition/inhibition in general? In other words the dog struggles to understand different social cues or know how to respond to them most appropriately, be this with other dogs or people. Or they might get different social signals ‘mixed’ up and thus switch rapidly, say, from more ‘friendly’ or even submissive behaviour to more aggressively defensive behaviour instead.
Dogs who have poorer social recognition can also have poorer social inhibition when it comes to reacting defensively, or aggressively, even towards those they know well or even live with.
MISTAKEN IDENTITY
The illustration you see here is a classic example of this. In that the dog has failed to recognise her owner under pressure. As a result, as he goes to stroke her she mistakes his hand coming into her head space as a more immediate threat and is about to launch a more defensive-lunge nip (picture 1). Then suddenly the penny drops. She is able to recognise the hand belongs to her owner, aborts the defensive response and behaves more affectionately again (picture 2). It also gives you a better ideal of just how rapidly a collie can both perceive and react to any sense of threat.
Overall, I hope this feature has given more insight into just how complex different forms of lunge-nipping behaviour in collies can be. In each dog, it revolves around their more individual levels of mental arousal, impulse control and capacities for social recognition/inhibition. As well as the readiness of the dog to launch this instinct in the first place.
In many dogs, this reflex will also predominantly be more of a ‘warn off’ behaviour, not intended to cause greater harm. Some dogs may only even ‘air snap’ after lunging. But if the biting ever comes more serious, or severe, then you are looking at a much bigger problem.
Meanwhile all aggression issues in Border collies are covered more comprehensively in BOOK THREE (green cover) of my BREED APART trilogy on BEHAVIOUR.
All text ©Carol Price 2025
Carol Price collie books: In the UK from: https://performancedog.co.uk/?s=carol+price In the USA from: https://www.dogwise.com/ # and https://www.cleanrun.com/product/border_collies_a_breed_apart_book_1_secrets_of_the_working_mind/index.cfm In Canada from https://4mymerles.com/collections/books In Australia from: https://gameondogs.com.au/ And in the Netherlands and Belgium from: https://mediaboek.nl/border-collies-a-breed-apart-book-1.html
