Handling can cause distress to marmosets. Capture should only be carried out if there is no alternative, e.g. for essential veterinary procedures.
To avoid direct handling marmosets can be trained to co-operate with husbandry procedures using a technique called ‘Positive Reinforcement Training’. Training can also lead to other benefits, including reduced levels of stress and boredom for the marmosets, and an improved relationship between carer and marmosets.
Handling
Marmosets do not like being picked up or handled in any way
They should only be captured if there is no alternative and only if it is absolutely necessary
Capture is necessary for veterinary work
Disadvantages of Direct Handling
Handling can cause fear and distress to marmosets.
Stress and upset may last for some time after handling has ended
Anticipation of being handled can also cause agitation and anxiety
Capture in nets or gloves can lead to injuries in the marmosets
Marmosets can get tangled in nets, or hurt while being chased
Marmosets tightly gripping mesh can damage their clawlike nails if forcibly removed
Capturing marmosets in their nest-box should be avoided: it is very important that marmosets have a place inside which they can always feel safe and secure
Recommended Handling Procedure
It is possible for marmosets to get used to being handling with nitrile/vinyl gloves if a lot of patience and time is spent gradually desensitising them using small treat foods
Hold the part of the tail nearest the body with the other hand around the shoulders, supporting their weight and keeping them upright
Be firm but gentle, lower your voice and move slowly and calmly, without sudden movements
Place marmosets back in their enclosure/cage as soon after handling as possible
Training
Direct handling can be avoided through a technique called positive reinforcement training (PRT)
Marmosets can be trained to cooperate with husbandry procedures
What is Positive Reinforcement Training?
Animals are given positive rewards (positive reinforcement) in response to the performance of a certain desired behaviour
Particular behaviours that are consistently paired with receiving a small food reward are more likely to be performed again
Initially, behaviours approaching the one you want can be rewarded
Offering Food
Is the first step of any training program
Initial approaches can be reinforced with rewards
Suitably tiny portions of rewards can be directed using a bamboo skewer (e.g. small bits of grape, raisin, marshmallow, banana chip or gum arabic)
Time and Training
Training does take some initial time investment, but surprisingly little
Marmosets take different amounts of time to learn
However, if marmosets are willing to accept food from your hand, they will take less time to train
Once trained to do something, marmosets will remember for long periods of time
Advantages of Training
Helps to create good relationships /improve the relationship between marmosets and their caregivers
Reduces the stress of the close presence of humans
Provides an enriching challenge to marmosets
Cooperation with Procedures
Some examples of husbandry procedures that marmosets can be trained to cooperate with:
Temperature readings
Palpations (test for pregnancy – trained care staff only)
Microchip reading and ultrasound
Weighing
Marmosets can be trained to hold different targets so that several marmosets housed together can be weighed separately, with no need for removal from their cage or handling home-cage weighing (as shown in the video above)
Moving Marmosets Between Cages and Enclosures
To move marmosets between cages marmosets can be trained to enter a transparent or mesh ‘carry-box’
The carry-box is attached to the cage and marmosets receive rewards for entering it (description of procedure)
Collar Cleaning
Marmosets can be trained to hold a target for some seconds for a food reward whilst they hold the target
They remain in one place, close to you, allowing their collar to be quickly cleaned
Return to Their Enclosure After Any Escapes
Trained marmosets can be enticed back with food rewards
Important: training done badly is even worse than when no training is done at all. It is essential to learn the correct techniques, ideally by going on a course.
