What is Enrichment?

Encourage Natural Behaviour

  • The captive environment should allow marmosets to express the full range of natural behaviour shown in the wild, including:
    • All positive locomotory behaviours and postures: leaping, running, climbing, clinging, hanging upside-down etc.
    • All social activities with other common marmosets: grooming one another, resting, playing and huddling etc.
    • Food-finding behaviour: capturing insects, gnawing trees for gum and working hard to get at and into fruits and other foods
    • The opportunity to explore novel items and environments
    • A safe, comfortable place to sleep and hide

Introduce Complexity

  • Complexity provides choice
  • Choice allows a degree of control and reduces the likelihood of boredom
  • Marmosets can only choose if they have a range of options presented to them. Complexity can be introduced through ‘enrichment’ in a variety of complementary ways
    • Enabling an active but harmonious social life
    • Changing their physical environment
    • Providing an appropriate variety of food in ways that present a challenge to reach it
    • Activities that challenge their minds and stimulate their senses
  • Movement of objects, structures or live animals can be enriching
  • Movement attracts attention and introduces unpredictability, for example:
    • swings to move and play on, loose objects like feathers to play with, live insects to chase, views through windows of live birds and humans etc.
  • Novelty and change reduce boredom. Marmosets quickly lose interest in some items
  • Frequent changes made to the enrichment can sustain attention and interaction
  • A rotation ‘timetable’ can be arranged so that different options are made available in turn, cycling through enrichment items then becomes easy and automatic for caregivers


  • Keep in mind, however, that excessive and swift change can be overwhelming (i.e. negative for welfare)
  • It is important that marmosets have as much control as possible
  • Control is linked to predictability and so reduces stress
  • Whilst having the opportunity to explore a variety of objects and situations, marmosets should always have the option of removing themselves from the stimuli

Evaluation and Safety

  • It is necessary to evaluate whether or not enrichment has improved welfare
  • Before introducing any enrichment it is essential to assess safety
  • Always watch the marmosets interacting with newly introduced enrichment to ensure it is safe
  • Some enrichment options will work better than others, some will not be effective at all, and some may have unexpected negative effects
  • Safety is an important consideration when adding architecture or objects to an enclosure; the Shape of Enrichment website includes a searchable safety database with anonymously posted information