Welfare of primates: normal behaviour patterns
All social primate species should show social behaviour. This includes physical actions, sounds and visual signals that are normal for the species.
Expectations of normal behaviour
Normal behaviour is expected from animals that are physically and mentally healthy. Changes in behaviour, or behaviour that is missing, can be important signs that there might be something wrong with the animal’s welfare.
Keepers should know the full range of normal behaviour for the species and for each animal they keep. This includes facial expressions, sounds, body positions and daily activities.
Signs of good and poor welfare amongst primates
Primate keepers should be able to recognise signs of good and poor welfare. Unusual behaviour can be a sign of disease, injury or stress. Keepers should also know what action to take if they see signs of poor welfare.
All social primate species should show social behaviour that is normal for their species. This includes physical behaviour, sounds and visual signals. Examples may include social grooming, sharing food, resting together and play, where this is normal for the species.
Primates should be kept in stable groups of a suitable size and mix so they can show the full range of these behaviours.
Social interaction and primates
Social contact with companions of the same species gives primates important stimulation and chances to learn. It also gives comfort, reassurance and enjoyment.
Removing a primate from its family or social group may harm its mental and physical welfare and may also affect the other primates. This is especially important for a mother and infant, and for species that form pair bonds.
Social grooming is a very important behaviour. It helps primates build and keep strong social bonds, gives comfort and reassurance, and helps keep the coat in good condition. However, too much grooming and hair plucking can be signs of poor welfare.
Social play can be one sign of good welfare. But older animals may not show this behaviour. Keepers should observe primates regularly and carefully to understand their overall behaviour.
Aggression and primates
Primates should not show ongoing aggression, antisocial behaviour or long-term conflict towards other animals or people.
This includes physical aggression, threats made by body movements or sounds, and aggressive displays. Conflict can be a normal part of life in social groups. However, dominant animals should not control or bully other primates in the group.
A primate may sometimes act aggressively towards its keeper, but repeated aggression is a cause for concern.
Short periods of sudden aggression are quite common in some primate groups. In most cases, social skills learned over time help keep this under control.
Keepers need a thorough understanding of behaviour that is normal for the species so they can judge what they observe correctly.
Persistent aggression and primates
Ongoing aggression can develop if the enclosure is too small or poorly arranged, so animals cannot move away from each other.
Animals that do not get the chance to learn normal social skills may also have problems living with other animals. Pain, frustration and an unsuitable environment can also lead to serious aggression.
Changes to the group can lead to aggression. Great care should be taken and expert advice should be sought to reduce these risks. Stable groups that live well together should not usually be changed.
Aggression can also happen in mixed-species enclosures because of the needs of each species or the behaviour of individual animals. The causes of aggression should be dealt with directly.
It is not acceptable to manage aggression by removing canine teeth for handling or care, or by keeping animals apart from the group for long periods.
Resources for keeping primates
When keeping primates, you should consider the following:
- the group and how it is made up
- changes to the group
- the size of the enclosure
- places where animals can hide from view
- easy access to food, water and other resources
- security
Primates should be able to protect themselves and move away when needed.
In the wild, primates that are in conflict can move away from each other and avoid physical or visual contact. They can also move to another area, for example when they reach sexual maturity.
Primates should also be able to move away from other things they find unpleasant or distressing.
Captive environments can limit these behaviours, which may cause stress. It is important to provide enough refuges and places where animals can hide from view, including from people.
Vertical space is especially important because primates often escape upwards, and social rank is often shown by where animals sit at different heights.
Self-grooming, feeding and drinking
Primates should show self-grooming, feeding and drinking behaviours that are normal for their species.
These behaviours are important for primates’ physical health and also give them stimulation.
Changes in these behaviours can be an early sign of a problem. For example, eating or drinking less may show a problem before there is any change in body weight or condition. Drinking or eating too much can also be a sign of a problem.
Self-grooming is normal behaviour. But too much grooming, which can be linked to stress and anxiety, may cause hair loss and skin sores. Hair-plucking is also a health concern, especially if the hair is swallowed and forms hairballs in the digestive system.
Primates should also show physical activities that are normal for their species.
These include:
- walking
- running
- climbing
- turning
- reaching
- stretching
- bending
- pushing
- pulling
- swinging
- jumping
Tarsiers, some lemurs and bush-babies usually cling to and leap between perches. Marmosets and tamarins cling to tree trunks, and gibbons swing from branch to branch. These primates must be able to carry out these natural activities to protect their physical and mental health.
It is important to give them access to an area that:
- has suitable features
- is the right size
- is designed so they can carry out natural behaviours
A change in activity levels, whether higher or lower, can be a sign of a welfare problem.
Sleeping and resting patterns and primates
Primates should show sleeping and resting patterns that are normal for their species and suitable for the individual animal.
Some primate species are active at night and sleep in the day. Others are active in the day and sleep at night. Some may be active both by day and night, or most active at dawn and dusk. The environment and the way it is managed should meet the needs of each animal.
The way primates sleep and rest varies between species. For example, some sleep together in groups in tree holes, while others build nests.
Enclosures should include suitable materials and features to support sleeping and resting behaviour for the species.
Sleeping or resting much more, or much less, than usual may be a sign of a welfare problem.
Foraging and primates
Primates should show a wide range of foraging behaviours that are normal for their species. These include exploring, searching for food, catching it, holding it, handling it, preparing it and eating it.
Primates spend a large part of the day looking for food, which may be spread out or found in small areas. They use strong memory and problem-solving skills when foraging. Some species also use tools to get food, for example to remove kernels from hard nuts.
Foraging behaviour varies greatly between species, and one species may use many different methods. For example, marmosets often make holes in trees to eat gum, but they also search for invertebrates among leaves.
Keepers should make sure their primates have enough chances to carry out all these behaviours, so they get both mental and physical stimulation.
Access to food for primates
Primates should not show anxiety about getting food.
Care should be taken to stop one animal becoming too dominant. All animals must be able to get every part of their diet. Food should be spread out well so that normal social ranking does not cause anxiety in lower-ranking animals or stop them from getting food.
Parenting behaviours and primates
If primates are allowed to breed, they should be able to show normal parenting behaviour for a suitable length of time for their species.
Young primates depend on their mothers for a long time, even after they stop feeding from them.
If infants are removed from their mother and family group too early, this can:
- stop them learning important survival and social skills
- lead to behaviour and hormone problems
- make it harder for them to live well with other primates
- leave them unable to care for their own young successfully
If the environment for breeding animals is poorly designed or not managed properly, this can:
- cause stress
- reduce fertility
- make mating more difficult
- affect how they care for their young, which may lead to abandonment, stealing young animals, or the death of infant primates
Activity and primates
Primates of all species show a wide range of activities and behaviours. Keepers should know what normal behaviour looks like in captivity for the species they keep.
A smaller range of behaviours, or less activity than usual, may show that the environment is not suitable for the animal’s needs or that the animal is unwell. A general lack of activity, or activity that is too limited, should be treated as a warning sign.
Scent-marking and primates
Scent-marking is normal behaviour for many primate species. It helps with social groups, social interaction, reproductive health and breeding behaviour.
Cleaning routines should be planned so they do not disrupt this form of communication.
Too much repeated behaviour, even if it is usually normal, should be treated as a warning sign.
Effect of poor welfare
Poor care can have a harmful effect on a primate’s behaviour. It may cause boredom, fear, pain and stress. If poor care continues for a long time, primates may start harming themselves. They may begin to show unusual behaviour, such as:
- regular signs of submission to other primates in public
- physical or vocal aggression
- anxiety
Suitable enrichment can help reduce these behaviours.
A stimulating environment for primates
Primate groups need an environment that is stimulating and gives each animal some control and choice.
An unsuitable environment may cause primates to show unusual behaviour. You should watch for any changes in behaviour, including:
- repeated unusual behaviour, such as pacing, rocking or self-clasping
- self-harm, such as self-biting
- withdrawn or low-mood behaviour
- other unusual behaviour, such as over-grooming, drinking urine or eating faeces
If primates develop unusual behaviour because of poor welfare, it may continue throughout their lives.
It is very important to take action to stop primates developing these behaviours. This action may include:
- providing a rich physical and social environment
- watching the primates closely
- looking for any changes in normal behaviour
- reviewing the environment regularly to make sure it still meets the animal’s needs
Signs of fear in primates
Signs of fear vary between species. They may include withdrawal, grimacing, too much lip smacking, aggression and certain sounds.
Some primates may have a natural fear of other species, such as dogs, cats or snakes. They should be protected from the distress of being kept close to these animals.
The herding or hunting behaviour of a dog can easily cause distress to a caged primate.