acting out

Question
I purchased a 13yo TB hunter 2 weeks ago with the help of my trainer (I'm back
in the saddle after 25 years).  He's been a bit excited since moving into his
new barn.  I have him on a regular turnout and lunge him before riding.  Some
days he is a perfect gentleman and other days, like today, he's naughty.  For
example, a lesson was underway and I brought him into the arena to free ride.  
When the lesson began to canter, he started acting out- prancing, bucking,
rearing. I tried to control him but his behavior persisted. I didn't was to
disrupt the lesson so I brought him outside and lunged him.  This has happened
twice in the past 2 weeks.  My trainer tells me this is absolutely normal
behavior for a horse getting accustomed to new surroundings.  My riding is improving but honestly I am
concerned about my ability to stay on him during these episodes (safety first).  
The barn I purchased him from from used a double wire and this is what I
currently use as well.  Thanks in advance for your advise."


Answer
His behavior doesn't surprise me one bit.  When he gets in the ring during the riding lessons, he might be feeling a bit of a herd instinct, and he might be wanting to play or make new friends.  What you need to do is watch for signs.  If he swishes his tail a bit before his fuss, or if he makes varied head cues, or a bit of a wiggle just before his bad behavior, then you have a common issue that can be quickly corrected.  If his temperament is shifting with no warning at all, then I would try to stand in the middle of the ring when the lesson riders are cantering.  You can also hop off and weight near the middle until they finish.  Safety is always a first priority for you, your horse, the lesson riders, and your trainer.  If you are not getting any warning signs, you will need to have your trainer do a bit of schooling with him.  

If you are getting a few clues ahead of time, try circling him.  When he is circling it is more difficult for him to buck.  Practice a few half halts too.  I feel that during these first few weeks while he is going through this transition, it is critical you don't over correct a most likely small problem stemming from the newness of the situation.  

Over all my best suggestion is for you and him to try to ride as often as you can during lessons.  The point of this is to desensitize him.  When the other riders canter, or when you feel him getting squirrelly, walk in to the center, and give yourselves a moment to watch while being quiet.  This will be the safest for everyone involved.  I am sure he will settle down once he has seen the routine enough times, and has had a chance to develop some new equine friends.