I often get asked why I have two herds here rather than one big one.
Two herds started when it became apparent to me that not all horses get on.. just like people, horsinality's clash! Some are more playful, some are funny about personal space, some just want a quiet life, and so having two herds gave me the way to keep all the horses happy and best matched personality wise! Size and/or age rarely comes into play..
It's also alot easier for me when it comes to feeding, poo picking and generally being within the herd when they are having a play and a hoon!
Orginally, both herds where mixed.
Over time, I now have one herd of 6 geldings, and one herd of 5 mares and 1 gelding.
Although horses living in mixed herds is natural, sadly, geldings are not natural.
We have experienced that this can have all sorts of complications with certain mare and gelding personality/hormonal clashes. Over the past few years, we have seen that lots of geldings seem to retain stallion-like behaviours, which can be brought to the surface when kept with mares, leading to mounting, guarding mares from other geldings and fights and stress amongst the herd. It can also cause the mares alot of stress when in season, as they seek out the geldings, again causing fights, mounting and other unwanted behaviours.
For this reason, we find its safer and calmer for all horses involved to have the herds (mostly!) split into sexes.
This doesn't mean we won't have two mixed herds again in the future, as it totally depends on what horses we have at the time.
If you have a gelding that has no stallion retained behaviours, or a small herd, or you don't mind your geldings mouting mares, then yes mixing can work well. I always had mixed herds when it was just my 4 horses with no issues, but when you add mares with heavy seasons, and/or geldings with retained stallion/colt behaviours, this can lead to carnage.
Sometimes, trying to keep things 'natural' doesn't work, so we must always have open eyes and assess the situation and each horse as an individual and not just assume they will 'sort it out'... especially when clients horses are involved!!