Friend's gelding is out for blood! Advice?

I just bought a 3 year old QH paint mare in October and I am currently boarding her at a friend's farm. My friend has a barn and two pastures (winter and summer). For the past couple weeks my mare has been alone in the winter pasture and occasionally in her stall in the barn. My friend's horses have been in the summer pasture. (The two pastures are separated and the horses have only seen and smelled each other from a distance) Yesterday I had to stall my horse and help move the other horses from the summer pasture down the the winter pasture for the season. After the move my friend suggested turning my mare out to see how the others would take to her. It was terrifying to say the least. My mare is super friendly and submissive to upon being turned out she slowly sauntered over to the herd to socialize and was immediately chased/kicked/and bit at. She tried fleeing as she is not a fighter but she was brutally pursued and cornered several times. I intervened after she was cornered and stalled her. We decided to try again today.. She was chased and driven off and on. The existing herd let her graze by herself for a while than they would get after her. (The existing herd consists of 4 mares and a gelding.. they are all standardbred x ponies and are smaller than my girl) The male seems to be the most aggressive when he persues her he doesn't let up when she tries to flee. The other mares will chase her a bit but let off when she runs away. I know it is normal for new horses to be chased off and for some fighting to happen in order for the new "pecking order" to be established. I'm just wondering how long will this last? Is it normal for a gelding in a herd of mares to be this aggressive with a new mare? My mare was previously kept at a farm where she was born and raised with her mother and younger brother so she is used to being with other horses. I am keeping her stalled and letting her out a couple hours a day and trying to supervise the interaction with the other horses (without interfering as much as possible). How long do you give it before you decide that two or more horses will just not get along? Any advice would help so much! Thanks!

Hello
I have had much expirence with joining new horses to the herd. I train horses to every month I have new horse coming through the gates of my pasture. I usually just let them loose. I have a very bossy mare who dosnt enjoy the change of horses much. But it usually takes her a day or 2 stop with the chasing and kicking. By the end of the week she is fine with the fact that there is another new horse in the pasture and there is nothing she can do about it. Yes it is very common when geldings are aggresive. Especially when they are the man on the pasture ( one gelding with 2 or more mares) they are use to being top man and they think they have to protect their ladies. Hope this helped :)

I would take out the gelding, let her settle with the others, once they are completely settled then start reintroducing the gelding pack into the herd.

After the last 'horsey war' I had here, turning horses back out to pasture, what I did to prevent a major injury was: I left 2 bossy mares together in a side pasture. I put 3 mares out in the large pasture.Let the 3 mares settle down, about 3 -4 hours, We fed the evening hay, let everyone eat, get Full bellies, then opened the gate and let the 2 bossy mares in with the others, but kept the small pasture open . I have a catch pen /area that joins 3 pastures , They squeeled and some chasing but no major wars.

Subbing..:) want hear thoughts too.

The only thing that really worries me is that the back of the barn opens into the pasture and she tries to linger around the back of the barn (I think she feels safe there because it is close to her stall). The other horses chase and corner her under the lean to / over hang behind the barn and its kinda close quarters. Especially with the old seeder that's sitting behind the overhang / lean to. She was being chased and tried to jump it once *shudders* They have so much open pasture to run in but they keep having all these blow outs right by the back of the barn (the least safe place to be). And I mean it when I say this gelding is NASTY! He was still pretty mean today but yesterday.. I thought he was trying to kill her. She is by far the youngest.. I think the youngest in the existing herd is like 8-10 years old. Could it also be an age diffece thing?

Are you able to put her and one other together for a while?

This is what I was thinking, too.

Probably not. It's been raining ALOT and the summer pasture is so swampy (that's why we moved the other herd when we did down the the winter pasture). The property owner went up today and removed the water trough and locked up the gate for the season. I don't want to stall her more than I have to. I hope they learn to get along soon :( .

Can you stall the gelding for a while to let the mares settle before letting the gelding in?