I had the most interesting experience today. I have a little horse, McKee, who has learned to do some scent work. It is a limited behavior in that the scent is on a mat, placed among other mats. He searches each mat until he smells the lavender scent (daubed on the mat on the underside) and then he stops and paws the mat.
It’s a fun behavior to watch, and even more fun because I can put that trick on the shelf for months at a time and yet he will still perform the behavior as soon as he sees the mats and gets the signal from me to start.
So today we had an interesting event. McKee had started to search for the mat for the third time; we had moved the mat to a new location and re-set the area. Just as he moved towards the mats my friend’s tabby cat went streaking by McKee, up the small path and climbed the tree. This startled the heck out of McKee who bolted off down the footpath about 50 feet.
Then he did something interesting. He skidded to a stop, turned around with tail flagged and trotted back to finish his task of finding the mat and indicating on it. We were pleased and bit surprised at his speedy recovery from that scary event. I hadn’t even had the time to call out “McKee” before he had rebounded.
I have clicker trained my horses since the late nineties. Time and again they’ve shown just how resilient they become once we start them on clicker training. I have all sorts of hypotheses as to why this occurs but the top of my list is because a behavior that’s built with positive reinforcement is very potent. As I see it, the hundreds of performances of a behavior creates a high likelihood of it being repeated. But it also overrides a fear response and the need to run away.
That’s the beauty. With McKee I didn’t do a thing in that moment. I didn’t analyze him to decide if he was afraid and then try to train him to be calm. The history with the behavior, the history of the all of our positively reinforced behaviors and the existing conditions combined to make the scary event fade quickly.
These kinds of events truly do reaffirm the many reasons why I train this way.
Here’s a video from several years ago, when he was just learning the behavior.
Clicker training horses - Peggy Hogan 
I had this experience very early in my clicker training career more than a decade ago. I had really only scratched the surface with my lovely cob mare who was very anxious and insecure. But her response one day, to all her friends disappearing from sight , and after her initial panic, was to return to her target and stick her nose on it. I realised that this was not only the most ethical but the most powerful tool in my training toolbox.