Straw and forage material ameliorate abnormal behaviors in adult chimpanzees

  • Published source details Baker K.C. (1997) Straw and forage material ameliorate abnormal behaviors in adult chimpanzees. Zoo Biology, 16, 225-236.


This study is summarised as evidence for the following.

Action Category

Primates: Scatter food throughout enclosure

Action Link
Management of Captive Animals
  1. Primates: Scatter food throughout enclosure

    A replicated, before-and-after study in 1996 in Atlanta, USA (Baker 1997) found that adding straw, into which food was scattered, reduced abnormal behaviours in laboratory-housed chimpanzees Pan troglodytes compared to bare floors with food presented in one place. The average abnormal behaviour observations were reduced from 10% when food was presented in one place to 4% when it was scattered. Repeated eating of regurgitated food was reduced from 5% to 1% and other abnormal oral behaviours from 4% to 1%. Non-oral abnormal behaviours were not reduced. No evidence of habituation was found over nine weeks. Chimpanzees were housed in five enclosures in groups of two or three. Two cups of mixed seeds and nuts were scattered in the straw of each of the enclosures twice daily. For each chimpanzee (n = 13), behaviour was recorded every 15 seconds over five minutes/day. Observations were carried out on 60 occasions (total of five hours) over three months both during the control and when food was scattered.    (CJ)


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