A friend and I share a barn with our combined 7 horses. The problem is with a horse that was added over the summer. She is a 15.5 hand pintaloosa mare that is built like a tank. She is big and muscular and she has a temper. Let me say she is NOT my horse and I never would have bought her...but she is there and now I have to deal with her.
It seems she wants to be the mare in charge (which is currently a pony appy cross mare)...but she doesn't target this mare, but another non-dominant mare. She actually got badly injured and injured that mare attacking her in the run-in shed a few weeks ago.
Here are the behaviors that concern me and I am just looking for advice for how to retrain or address them.
1. Unpredictable nasty behavior. She is confined to a tie stall right now due to a severe leg laceration she got 2 weeks ago. When we're working around her things will be fine. Until they are not. She will kick at us out of the blue or all of a sudden swing her head around and bite.
2. Aggression towards the other horses. I can accept and understand normal herd dynmaics...but how do you address it if she "targets" one horse?
Again, I would never have added this horse to my herd, but my friend has. The idea of selling her came up several times but it is not something he will consider...so I want to figure out how to work with her and try to modify her behavior.
Thank you for any advice you can share.