Maracas for Macaca? Evaluation of three potential enrichment objects in two species of zoo-housed macaques (2000)

Vick, S.-J., Anderson, J. R., Young, R.

Abstract

One group each of Barbary macaques and stump-tailed macaques, both zoo-housed, received hard replica fruits in three experimental conditions: as empty (unresponsive) objects, as maracas that rattled when manipulated (simple responsive), and as objects from which food items could be extracted (foraging devices). Both groups manipulated the replica fruits most when they functioned as foraging devices, and responsiveness tended to decrease within sessions in all conditions.