Monitoring the social behavior of a bachelor mandrill (Mandrillus sphinx) dyad participating in touchscreen-mediated cognitive testing.

Cognitive testing of primates in zoos is becoming increasingly common. Cognition experiments are generally thought to be beneficial as they provide participants with an opportunity to engage in species-specific cognitive functioning, perhaps more so than with traditional forms of environmental enrichment. However, testing may increase competition and aggression between conspecifics if it has monopolizable features or creates social tension within groups. The purpose of this study was to monitor the social behavior of a bachelor mandrill (Mandrillus sphinx) dyad participating in a touchscreen-mediated cognition study. The mandrills' behavior was monitored before and after testing sessions for 8 months. Positive changes in the mandrills' affiliative behavior were observed. Rates of play, presentations, and silent bared-teeth face increased posttesting. No change in rates of agonism were observed between pre- and posttesting conditions. The observed positive changes in affiliative behavior suggest cognitive testing was enriching for the mandrills and participating in testing improved their welfare. Zoos beginning cognitive studies should monitor participant behavior to ensure their welfare is not compromised and is, ideally, enhanced.