Horses are gregarious, social creatures – but how much do we really know about how they make friends?

Horses are highly social animals, often forming many strong bonds and friendships over the course of their lifetime. There are clear evolutionary reasons for this, as Dr Claire Ricci-Bonot, a postdoctoral researcher at INRAE (France's National Research Institute for Agriculture, Food and the Environment), explains.

“It’s important to remember that horses are generally gregarious animals who live within complex social systems,” she says. “For them, the group means safety and survival, so their brains are adapted to seek out partners.”

Social interaction is so important for horses, it’s recognised within the five freedoms of equine welfare.

“We know that developing and maintaining social relationships and hierarchical positions are second only to getting food in what horses do all day, given the opportunity,” says equine behaviour consultant Dr Debbie Marsden.

“This is not surprising as for herd animals like horses, ‘fitting in’ and ‘getting along’ is vital for survival, and a network of established relationships is essential to minimise aggression and conserve energy.”

Given horses are hardwired to rely on social bonds for survival, it’s no wonder they’re picky about their friends.

“Horses living in a group tend to have one to three preferred partners; they often spend a lot of time together and synchronise their activities,” says Claire.

But, as anyone who’s ever tried to integrate a new horse into an existing group knows, predicting where horse friendships will blossom isn’t easy. It’s an area of equine behaviour in which Debbie would like to see more research.

“We don’t know which horses will get along or become friends until we put them together,” she says. “It would be really useful to be able to ‘profile’ or predict this.”

Becky Moody on matchmaking equine neighbours and forming horse friendships

For international dressage rider Becky Moody, giving the horses on her yard the opportunity to socialise is important but requires careful matchmaking.

“It can be difficult to manage on a yard like this, as you have a lot of strong characters in your competition horses!” she says. “So I 100% choose carefully. Some horses, when turned out, are relatively solitary, not bothered about the one that’s next to them, and then others spend the entire time playing with each other.”

When Becky put in round pens for winter turnout, socialising was an important factor in their design.

“The pens are in pairs and we have a low bit between them, so the horses can interact and they do spend a lot of time playing with each other. That was really important to me, that they had that opportunity.”

Lizzie Wray is the yard owner at Shadowmere Equine Retirement Livery, Lincs. Whenever a new horse arrives, she uses their 14-day biosecurity procedure to get to know the horse and their personality, before choosing which she thinks is the most suitable group for them to join.

“We then bring the group we think will be good to the next paddock, and let them get to know each other safely, over the fence,” she says. “Once we’re happy, we’ll introduce the newbie into the herd.”

Even then, she doesn’t take any chances.

“Say we’re introducing a fourth horse to an existing group of three, we always have four members of staff on hand in case it doesn’t work and we need to remove the newbie and rethink.

“We have come across ones that hate each other,” she continues. “We’ve got one mare who just doesn’t like this one gelding – she can’t even look at him, the poor boy is doing nothing to her!”

Lizzie says it can take two or three weeks for a group to settle, but if it’s not working, they’ll try something else.

“If they don’t get on, or it’s not meeting their needs, then we’ll try another group.”

Some horses seem to struggle more socially than others.

“It does seem to be a particular characteristic of the bullied animal, not the bullies, but we don’t know how to assess for it,” says Debbie.

“They may just not be giving out the ‘expected’ social signals, or giving out the wrong ones. And there may be as yet unknown pheromonal signs or some other communication we’re not aware of.”

It’s thought poor social skills stem from the horse’s upbringing and a lack of opportunity to interact at an early age, and Debbie says it’s unclear if this can be corrected in later life.

“We don’t know how to teach or improve these social skills, other than by offering varied social experiences in later years.”

A healthy, well-established equine bond is characterised as much by what we don’t see as what we do, which presents a challenge when trying to study it.

“Simple ‘acceptance’ and ‘tolerance’ is a huge part of equine social behaviour. It’s hard for scientists to measure or investigate ‘nothing happening’,” explains Debbie.

“There is probably a lot more communication and subtle social behaviour going on than we are aware of. One thing we do know is that, once established, these relationships last for a great many years.”

For Lizzie, running a retirement livery means facing the inevitable – having to manage a horse whose close companion has died.

“Horses absolutely grieve,” she confirms. “We had two geldings who were particularly drawn to each other and very happy, but the younger one was sadly riddled with arthritis and had to be put to sleep.

“For two weeks afterwards, the surviving gelding was completely off his food and lethargic. We thought he was going to die of a broken heart, but eventually he quietly slipped into the other herd and they seemed to support him.”

Lizzie is a big advocate of allowing horses to see what’s happening when a horse is euthanised, “So they can process it, and they don’t think, where’s he gone?”

Apart from the unavoidable end of life, Lizzie and her team try not to separate any of the horses on their yard.

“These horses are not out competing,” she points out. “They come in through the gates and don’t leave until it’s time for them to be put to sleep. We don’t turn out or bring in alone, and if a horse is on box rest for some reason, they always have a buddy.”

On a busy competition yard, where horses are constantly coming and going, managing attachments requires careful consideration, as five-star event rider Millie Dumas explains.

“You have to find the right groups of horses to take to a show, for example, and sometimes you have to separate horses so that an attachment doesn’t become a performance issue,” she says. “If you want to get the best out of them, they also have to be happy and content in their home environment. We don’t want stressed horses.”

Separation anxiety in horses – what we know

Separation anxiety is something many owners are aware of, but surprisingly little is actually known about it. In her previous role at the University of Lincoln, Claire undertook a study into owners’ experiences of separation anxiety. The results, based on 88 responses, were published earlier this year.

“More than 90% of the respondents believed they had a horse that had suffered with separation anxiety or knew someone owning a horse who they believed had suffered from separation anxiety,” she says. “However, in the scientific literature, little is known about separation anxiety despite it being commonly discussed in the popular press and by owners.

“Our research demonstrated that it’s more complicated than we might think.”

The research found that how separation anxiety manifests differs from horse to horse. It was observed in different contexts, as it depended on whether the horse was being left behind or was actively leaving, and occurred at different points during the process.

“This was separated into ‘during preparation’ for departure, when ‘actively leaving or being left’, when there is an ‘initial barrier to contact’ and finally when there is a ‘loss of contact’,” Claire explains.

“Moreover, we identified several signs potentially associated with separation anxiety, ranging from increased arousal – for example hypervigilance – to apathy.”

The research concluded that care needs to be taken not to overgeneralise.

Claire also points out that more research is needed on how to prevent separation anxiety occurring.

“There’s no scientific literature on the benefits of training horses through graduated periods of controlled isolation to cope with separation from a companion or group,” she says. “Until we get more data, our recommendations remain ‘best guess’.

“However, gradually training young horses to cope with separation as a preventative measure is advisable.”

For Millie, this training is an important part of a horse’s education. She’s seen first-hand the problems that can occur without it.

“We’ve had liveries in the past, often older horses that have perhaps lived their life with one other horse and gone everywhere together. Because they’ve never been taught to be independent, they’ve become insecure without their companion by their side,” she says.

“We’ve managed these types of horses by making sure that they have the right sort of company next door to them, ones who give off a calm demeanour.

“It’s important to teach horses from a young age gradually to be independent as well as have company, to be able to leave it and come back,” she explains.

“We have a lot of young horses and I think it’s really important they learn that, as well as having that downtime where they can socialise with other horses.”

Becky agrees, and adds that hacking can play a big part in this early training.

“We hack all our young ones a lot, they do always hack in pairs and getting each one to walk in front and be confident makes a big difference to how they are at a competition.”

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