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North Hills Monthly

What is Reactivity?

Nov 30, 2019 10:41AM ● By North Hills Monthly magazine

By Liesl Wiesen, Behavior Coordinator

You might hear a trainer, behavior consultant, veterinarian or Internet expert describe an animal as being reactive, but what exactly does that term mean, and how is it different than aggressive?

Simply put, reactive means that an animal is responding to a situation in a seemingly exaggerated way. Reactivity is a spectrum of behavior that can be used to describe a cat that runs away from a child, a dog that whines during a nail trim or a rabbit that bites the veterinarian during an examination.

Reactivity comes in different types that are identified by the cause of the behavior; for example, dog reactivity caused by encountering other dogs. Fear caused by a trigger (such as a dog, child, or vet) underlies most of the behavior that the animal displays. There are also other common causes like overexcitement.

Recognizing reactivity as a spectrum of behavior caused by a trigger and driven by fear or over-excitement gives us a different way to look at and think about behavior. If a trigger can be identified, such as the presence of another dog, then the behavior can be managed and modified. The dog should not be taken to a dog park and obedience training may be able to help modify these reactions.

If you can read an animal’s body language and see that fear or overexcitement is the driving force behind their behavior, such as a cat that is fearful of new people, the needs of the animal are recognized and can be managed. In this case, the cat should be given a safe place to retreat where visitors are not going to force an interaction.

Aggression is at the extreme end of the reactivity spectrum. The term aggression should be reserved for those situations in which the animal intends to cause serious harm when only a minor trigger–or no trigger at all–can be identified. Aggression is an extreme overreaction to a situation. Simply labeling an animal as aggressive tends to prevent further investigation into the true nature and cause of the behavior as well as potential solutions.

Both reactive and aggressive animals can benefit from behavior management, modification and medication, so it’s best to seek guidance from a behavior or veterinary professional. If you are struggling with a reactive pet, you can ask your veterinarian for a reference or contact Animal Friends’ Behavior team at