Head-cock Stare

  • Marmoset moves head very slowly from side to side while looking at an animal or object
  • First seen at 1 week old
  • Young marmosets head-cock more than older marmosets
  • May give the marmoset a better view of what they are observing
  • Usually positive as exploratory

Withdrawal Gesture

  • Marmoset moves body away with arms still held out or slightly extended
  • Fearful response during conflict or reaction to a close threat


  • Like the withdrawal gesture but more extreme: arms and legs may be bent
  • Extremely fearful behaviour


  • Marmoset stands on its legs, and may stare in a fixed direction for several seconds
  • Performed in response to a strange sound or object

Hang by Feet

  • Marmoset hangs upside-down by its feet
  • Helps improve range of reach
  • Positive behaviour

Vertical Cling

  • Marmoset clings to a vertical object
  • Positive, natural behaviour


  • Marmoset rests on their front on a long perch or branch, with hands and legs draped down either side
  • A position of extreme relaxation, unfortunately rarely seen in captivity
  • Positive welfare indicator

Piloerection/Bristle: Hair Standing on End

  • Marmoset’s hair stands erect, either all over the body or just on the tail (then resembles a bottle-brush)
  • Associated with anxiety and also with confrontation, agitation and aggression
  • Negative welfare indicator


  • Whilst sitting the marmoset sways from side to side making alarm calls
  • Occurs in response to a situation that causes alarm. Behaviours can tell you a lot about welfare- negative welfare indicator