Horses have evolved over millions of years to live in groups - for prey animals there is safety in numbers. They depend on other herd members to alert them to potential danger and to watch over them while they sleep and relax. So naturally horses do form strong attachments and will often form a ‘pair bond’ for life – a close relationship with another horse, often a similar age, height and size to themselves. A horse on his own is in a dangerous situation and must be constantly vigilant - any lapse of concentration could be a matter of life or death.
In contrast, our domestic horses are often turned out in individual paddocks, or in constantly changing herds, never having the opportunity to form these friendships. Some horses can become very distressed by this upheaval. Horses who were weaned at too early an age or had a sudden, traumatic separation from their dam are likely to suffer from separation anxiety. Horses who have been isolated from others or been frightened when separated from their herd may also become fearful of leaving the safety of the group again.
For a horse to being anxious at being alone could be considered a normal behaviour. It is our responsibility to train our horses to be separated from others and ensure they are confident to be alone. This is best approached by changing how the horse feels about being alone very gradually, so as to avoid reinforcing their fear. If they only have good experiences when separated and the length of time spent apart is increased a little at a time, their confidence will grow and they will realise they will always be returned to their friends and there is nothing to fear.
Tips for dealing with separation anxiety
If your horse is attached to another individual, start a gradual training plan to practice short separations of a minute or so at first, then gradually increase the length of time they are separated. Ensure both horses have calm, well-socialised equine company and they have a good experience when separated - eg. a feed, praise, a lip-curling wither scratch or a food reward.
Don't force your horse to leave others, leave him on his own or punish him if he is anxious. This will only reinforce his fears and may make matters worse.
If your horse will be alone for a specific situation e.g. a vet or farrier visit and you think they may struggle, ask to have another calm horse present. If not, ensure your horse has access to a haynet or feed to occupy him. In more severe cases it is advisable to employ a qualified behaviourist to help create a step-by-step programme to find the best long term solution.